JP2012128945A - Storage medium, reproduction method, and recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a storage medium which includes organic pigment material with which recording/reproduction can be performed with light of wavelength of 620 nm or less, and to provide a recording method and recording device in which the medium is used.SOLUTION: Light absorption rate is drastically decreased at light of wavelength of lower than 620 nm due to effect of light absorption performance of conventional organic pigment material, and recording sensitivity is decreased. By using "L→H" organic pigment recording material which has a reflecting rate which is higher in a portion recorded (a recording mark) than in a portion not recorded, substrate deformation is not needed by formation of the recording mark utilizing decoloration effect due to separation of electronic bonds, and the recording sensitivity is enhanced.

Description

  The present invention relates to a storage medium such as an optical disk, a reproducing method thereof, and a recording method thereof.

  A DVD (Digital Versatile Disc) is known as a high-density optical disc capable of recording video and the like. In a recordable DVD, the address is embedded by wobbling the side wall of the recording track (groove). Information recorded on the optical disk such as address information is recorded from sync mark to sync mark (see Patent Document 1).

  In Document 1, only 2 bits in the reserved area correspond to the non-modulation area, and other information recording locations correspond to the modulation area. Considering this correspondence, in Patent Document 1, most of the wobble information is a modulation area in which information such as address information is recorded, and the length of the reserve area corresponding to the non-modulation area is very small. For this reason, there is a disadvantage that synchronization cannot be stably performed using a non-modulation area having a constant wobble pattern, and signal detection accuracy in the modulation area is poor.

US Pat. No. 5,835,478 (FIG. 7)

  As described above, the conventional wobble address type storage medium has a disadvantage that the size of the non-modulation area is smaller than that of the modulation area, so that synchronization cannot be stably performed and signal detection accuracy in the modulation area is poor.

  An object of the present invention is to provide a storage medium, a reproducing method, and a recording method capable of stably performing synchronization using a non-modulation area having a constant wobble pattern and improving the signal detection accuracy in the modulation area. It is in.

  In order to solve the above problems and achieve the object, the present invention uses the following means.

  (1) A storage medium according to the present invention has a modulation area in which address information is recorded and a non-modulation area in which no information is recorded in a storage medium in which address information is recorded by wobble. Is wider than the total length of the modulation area.

  (2) The reproduction method of the present invention has a modulation area where address information is recorded by wobble and a non-modulation area where no information is recorded, and the total length of the non-modulation area is greater than the total length of the modulation area Information is reproduced by irradiating a wide storage medium with laser light.

  (3) The recording method of the present invention has a modulation area in which address information is recorded by wobble and a non-modulation area in which no information is recorded, and the total length of the non-modulation area is greater than the total length of the modulation area. Information is recorded by irradiating a wide storage medium with laser light.

  According to the present invention, it is possible to provide a storage medium, a reproducing method, and a recording method capable of stably performing synchronization using a non-modulation area having a constant wobble pattern and improving signal detection accuracy in the modulation area. Can do.

The figure which shows a standard phase change recording film structure and an organic dye recording film structure. Explanatory drawing of an example of the light absorption spectral characteristic of the organic dye recording material used for the present DVD-R disc. FIG. 4 is a diagram showing a comparison of formation shapes of recording films in a prepit region or a pregroove region 10 in a phase change recording film and an organic dye recording film. The figure which shows the specific plastic deformation state of the transparent substrate 2-2 in the recording mark 9 position in the write-once information storage medium using the conventional organic pigment | dye material. Explanatory drawing regarding the shape and dimension regarding a recording film which makes it easy to raise | generate a recording principle. FIG. 3 is a characteristic explanatory diagram of the shape and dimensions of a recording film. FIG. 4 is an explanatory diagram of light absorption spectrum characteristics in an unrecorded state in an “H → L” recording film. Explanatory drawing of the light absorption spectrum characteristic in the recording mark in an "H-> L" recording film. BRIEF DESCRIPTION OF THE DRAWINGS Structure explanatory drawing of one Embodiment of the information recording / reproducing apparatus of this invention. The figure which shows the detailed structure of the peripheral part containing the synchronous code position extraction part 145 shown in FIG. The figure which shows the signal processing circuit using a slice level detection system. The figure which shows the detailed structure in the slicer 310 of FIG. The figure which shows the signal processing circuit using the PRML detection method. FIG. 14 is a diagram showing a structure in the Viterbi decoder 156 shown in FIG. 9 or FIG. 13. The figure which shows the state transition in PR (1, 2, 2, 2, 1) class. The figure which shows the waveform (write strategy) of the recording pulse which test-writes in a drive test zone. The figure which shows the definition of a recording pulse shape. The figure which shows the light reflectivity range of an "H-> L" recording film and an "L-> H" recording film. FIG. 7 is an explanatory diagram of polarities of detection signals detected from an “H → L” recording film and an “L → H” recording film. Explanatory drawing of the light absorption spectrum characteristic in the unrecorded state in an "L-> H" recording film. The figure showing the light absorption spectrum characteristic change in the recorded state and the unrecorded state in the “L → H” recording film. The figure which shows an example of the structure and dimension in an information storage medium. The figure which compares the detailed data structure in the system lead-in area | region SYLDI and the data lead-in area | region DTLDI in various information storage media. The figure which shows the data structure in the RMD duplication zone RDZ in the write-once information storage medium, and the recording position management zone RMZ. The figure which shows the comparison of the data structure in the data area | region DTA and the data lead-out area | region DTLDO in various information storage media. The figure which shows the data structure in the recording position management data RMD. The figure which shows other embodiment different from FIG. 26 regarding the structure of the border area | region in a write-once information storage medium. Explanatory drawing about the structure of the border area | region in a recordable information storage medium. The figure which shows the data structure in control data zone CDZ and R physical information zone RIZ. The figure which shows the data structure in data ID. Explanatory drawing of other embodiment regarding the data structure in a control data zone. The figure which shows the outline of the conversion procedure until it comprises a physical sector structure. The figure which shows the structure in a data frame. The figure which shows the circuit structure of the initial value given to a shift register at the time of creating the frame after a scramble, and a feedback shift register. Explanatory drawing of ECC block structure. Explanatory drawing of the frame arrangement | sequence after a scramble. Explanatory drawing of the interleaving method of PO. Explanatory drawing of the structure in a physical sector. The figure which shows the detailed structure of the ECC block after PO interleaving shown in FIG. Explanatory drawing of the example of a light absorption spectrum characteristic change before and behind recording in an "H-> L" recording film. Explanatory drawing of the example of a light absorption spectrum characteristic change before and behind recording in a "L-> H" recording film. FIG. 3 is an explanatory diagram of a change in molecular structure in an azo metal complex. Explanatory drawing of the other example of the light absorption spectrum characteristic change before and behind recording in an "L-> H" recording film. Explanatory drawing of the other example of the optical absorption spectrum characteristic change before and behind recording in a "H-> L" recording film. Explanatory drawing of another example of the light absorption spectrum characteristic change before and behind recording in an "H-> L" recording film. Explanatory drawing of the prepit cross-sectional shape in the system lead-in area SYLDI. Explanatory drawing of a reference code pattern. The figure which shows the comparison of the data recording format (format) for every various information storage medium. The comparison explanatory drawing with the prior art example of the data structure in various information storage media. The comparison explanatory drawing with the prior art example of the data structure in various information storage media. Explanatory drawing of 180 degree phase modulation and NRZ method in wobble modulation. FIG. 5 is an explanatory diagram of a relationship between a wobble shape and an address bit in an address bit area. The comparison explanatory drawing of the positional relationship in a wobble sync pattern and a wobble data unit. Explanatory drawing regarding the data structure in the wobble address information in a write-once information storage medium. Explanatory drawing of the arrangement | positioning location of the modulation area | region on a write-once information storage medium. Explanatory drawing of the arrangement | positioning location of the modulation area | region in the physical segment on a write-once information storage medium. The layout explanatory drawing in a recording cluster. The figure which shows the data recording method of the rewritable data recorded on a rewritable information storage medium. Explanatory drawing of the data random shift of the rewritable data recorded on the rewritable information storage medium. Explanatory drawing of the write-once method of write-once data recorded on a write-once information storage medium. The figure which shows the structure of the picket code (error correction block) in B format. Explanatory drawing of the wobble address in B format. The figure which shows the detailed structure of the wobble address which combined the MSK system and the STW system. The figure which shows the track structure of B format. The figure which shows the recording frame of B format. The figure which shows the structure of a recording unit block. Diagram showing the structure of data run-in and data run-out. The figure which shows arrangement | positioning of the data regarding a wobble address. Explanatory drawing of the guard 3 area | region arrange | positioned at the end of a data run-out area | region. The figure explaining the other Example of the detection signal level in the H format in an "H-> L" recording film. The figure explaining the other Example of the detection signal level in the H format in an "L-> H" recording film. The figure explaining the relationship between the detection range of the preamplifier 304, and a detection signal level. The figure explaining the wobble address format in the recordable information storage medium of this embodiment. The figure explaining the characteristic of a wobble signal and a track shift signal.

  Hereinafter, embodiments of a storage medium, a reproducing method, and a recording method according to the present invention will be described with reference to the drawings.

<< Summary of Features and Effects of Embodiments of the Present Invention >>
(1) Relationship between track pitch / bit pitch and optimum recording power: In the case of the recording principle with the substrate shape change as in the past, when the track pitch is clogged, "cross write" and "cross erase" occur, and the bit pitch is reduced. Intersymbol crosstalk occurs. By devising a recording principle that does not involve a change in the substrate shape as in this embodiment, the track pitch / bit pitch can be narrowed and the density can be increased. At the same time, according to the above recording principle, the recording sensitivity is improved and the optimum recording power can be set small, so that high-speed recording and multi-layered recording films are possible. (2) ECC block with 620 nm or less short wavelength optical recording Each data ID information in two consecutive sectors, which is configured by a combination of a plurality of small ECC blocks, is arranged in different small ECC blocks. According to this embodiment, as shown in FIG. In order to use the local optical characteristic change in the recording layer 3-2 as a recording principle, the temperature reached in the recording layer 3-2 during recording is the plastic deformation of the transparent substrate 2-2 or the heat of the organic dye recording material. It is lower than the conventional recording principle by decomposition and vaporization (evaporation). Therefore, the difference between the reached temperature and the recording temperature in the recording layer 3-2 during reproduction is small. In the present embodiment, the interleaving process between small ECC blocks and the arrangement of data IDs in one ECC block are devised to improve the reproduction reliability in the event that the recording film deteriorates during repeated reproduction.

(3) Recording is performed with light having a wavelength shorter than 620 nm, and the recorded portion has higher reflectance than the non-recording portion. The light having a wavelength shorter than 620 nm is greatly affected by the absorption spectral characteristics of a general organic dye material. As a result, the light absorptance decreases and the recording sensitivity decreases. Therefore, a very large exposure amount is required to generate the substrate deformation that is the recording principle of the conventional DVD-R. By adopting “L → H” organic dye recording material whose reflectance is higher in the recorded part (record mark) than in the non-recorded part as in the present embodiment, the “decoloring effect by separation of electronic bonds” is used. The formation of the recorded mark eliminates the need for deformation of the substrate and improves the recording sensitivity.

4). 4. “L → H” organic dye recording film and PSK / FSK modulated wobble groove: wobble synchronization during reproduction is easy and reproduction reliability of wobble addresses is improved. “L → H” Organic Dye Recording Film and Reproduction Signal Modulation Determining ... A high C / N ratio for the reproduction signal from the recording mark can be secured, and the reproduction reliability from the recording mark is improved. 6. Light reflectivity range at “L → H” organic dye recording film and mirror section: A high C / N ratio for a reproduction signal from the system lead-in area SYLDI can be secured, and a high reproduction reliability can be secured. Light reflectance range from “L → H” organic dye recording film and unrecorded area during on-track… High C / N ratio for wobble detection signal in unrecorded area can be secured, and high reproduction reliability for wobble address information To secure the sex. “L → H” organic dye recording film and wobble detection signal amplitude range: A high C / N ratio for the wobble detection signal can be secured, and a high reproduction reliability for wobble address information can be secured.
" table of contents "
Chapter 0 Description of relationship between used wavelength and this embodiment ... Explanation of used wavelength in the scope of application of this embodiment Chapter 1 Explanation of combination of information storage medium components in this embodiment The contents and the explanation of the combination method are shown.

Chapter 2 Explanation of Differences in Reproduction Signals between Phase Change Recording Film and Organic Dye Recording Films 2-1) Differences in Recording Principle / Recording Film Structure and Basic Concepts Regarding Generation of Reproduction Signals ... Definition of λmax write 2-2 ) Differences in the shape of the light reflecting layer in the prepit / pregroove region Effects on the shape of the light reflecting layer (difference between spin coating and sputter deposition) and the reproduction signal Chapter 3 Features of the organic dye recording film in this embodiment 1) Problems with high density in a write-once recording film (DVD-R) using a conventional organic dye material 3-2) Basic characteristic explanation common to the organic dye recording film in this embodiment. Lower limit value, channel bit length / track pitch that produces the effect in this embodiment, the number of repetitive playbacks, optimum playback power,
Ratio of groove width to land width ... Relationship with wobble address format,
Relationship between recording layer thickness at groove and land,
Technique for improving error correction capability of recording information and combination with PRML 3-3) Recording characteristics common to organic dye recording film in this embodiment: upper limit value of optimum recording power 3-4) “H → L” in this embodiment ”Characteristics concerning recording film… upper limit of reflectance of unrecorded,
Relationship between the value of λmax write and the value of λlmax (maximum absorbance wavelength at unrecorded / recorded position) Relative value range of reflectance, modulation at the unrecorded / recorded position, and absorbance value at the reproduction wavelength ... n k Range Relationship between Required Resolution Characteristics and Upper Limit of Recording Layer Thickness Chapter 4 Description of Playback Device or Recording / Playback Device and Recording Conditions / Playback Circuit 4-1) Structure and Features of Playback Device or Recording / Playback Device in the Present Embodiment Description: Use wavelength range, NA value, RIM Intensity
4-2) Description of Reproduction Circuit in this Embodiment 4-3) Description of Recording Conditions in this Embodiment Chapter 5 Description of Specific Embodiment of Organic Dye Recording Film in this Embodiment 5-1) This Embodiment Description of characteristics relating to “L → H” recording film in ・ ・ ・ Recording principle, reflectance and modulation at unrecorded / recorded position 5-2) Characteristics of optical absorption spectrum related to “L → H” recording film of this embodiment. Maximum absorption wavelength λmax write value, Al405 value and Ah405 value setting condition 5-3) Anion part: azo metal complex + cation part: Dye 5-4) Azo metal complex + “copper” used as central metal… Recording The light absorption spectrum later spreads in the “H → L” recording film and narrows in the “L → H” recording film. Maximum value of maximum absorption wavelength change before and after recording Maximum value of change in absorption wavelength Maximum value before and after recording Absorption wavelength change is small and maximum (maximum Chapter 6 description of the pre-groove shape / pre-pit shape in coating type organic dye recording film and on light reflection layer interface 6-1) Light reflection layer absorbance at the absorption wavelength varies (material and thickness)
... Thickness range and passivating structure ... Recording principle and prevention of deterioration (Substrate deformation and signal deterioration more easily than cavity)
6-2) Explanation of pre-pit shape at the interface between coated organic dye recording film and light reflecting layer ... Effect of widening track pitch / channel bit pitch in system lead-in area Playback signal amplitude value and resolution light in system lead-in area Specification of the level difference between the land portion and the pre-pit portion in the reflective layer 4-2 6-3) Description of the pre-groove shape at the interface between the coated organic dye recording film and the light reflecting layer. Of the step difference between the head portion and the pre-groove portion Push-pull signal amplitude range Wobble signal amplitude range ... Combination with the wobble modulation method Chapter 7 Explanation of the first next generation optical disc: HD DVD method ... Recording principle and countermeasures against degradation of reproduced signal (Signal degradation is more prone to substrate deformation and cavity) ... Error correction code ECC structure, PRML (P artial Response Maximum Likelihood) Method Relationship between wide flat area in groove area and wobble address format Multiple recording is performed in VFO area which is non-data part at the time of additional recording
... The influence of the DC component change in the multiple writing area is reduced. The effect is particularly remarkable in the “L → H” recording film.

Chapter 8 Second Next Generation Optical Disc: Explanation of B Format ... Recording Principle and Reproduction Signal Deterioration Countermeasure (Signal degradation is more likely than substrate deformation or cavity)
Relationship between wide flat area in the groove area and wobble address format Multiple recording is performed in the VFO area which is a non-data part during additional recording.
... The influence of the DC component change in the multiple writing area is reduced. The effect is particularly remarkable in the “L → H” recording film.

  This embodiment will be described below.

Chapter 0 Explanation of Relationship between Wavelength Used and This Embodiment As a recordable information storage medium using an organic dye material as a recording material, a CD-R disc using a recording / reproducing laser light source wavelength of 780 nm, and a recording / reproducing DVD-R discs using a laser light source wavelength of 650 nm are already commercially available. Furthermore, in the next-generation write-once information storage medium with a higher density, the laser light source wavelength for recording or reproduction is around 405 nm in either the H format (D1) or B format (D2) of Table 1 described later ( That is, it is assumed that the range of 355 nm to 455 nm is used. In a write-once information storage medium using an organic dye material, the recording / reproducing characteristics change sensitively only by slightly changing the wavelength of the light source used. In principle, the density is increased in inverse proportion to the square of the recording / reproducing laser light source wavelength. Therefore, it is desirable that the laser light source wavelength used for recording / reproducing is shorter, but for the above reasons, a CD-R disc or DVD is used. -The organic dye material used for the R disk cannot be used as a write-once information storage medium for 405 nm. In addition, since 405 nm is close to the ultraviolet wavelength, a recording material that can be “recorded easily with 405 nm light” is likely to change its characteristics when irradiated with ultraviolet light, and has a drawback of lacking long-term stability. Since characteristics vary greatly depending on the organic dye material used, it is difficult to conclude as a general theory, but as an example, the above characteristics will be described with specific wavelengths. The organic dye recording material optimized with 650 nm light changes its recording / reproducing characteristics when the light used is shorter than 620 nm. Therefore, when recording / reproducing is performed with light shorter than 620 nm, it is necessary to newly develop an organic dye material that is optimal for the light source wavelength of recording light or reproducing light. Organic dye materials that are easy to record with light shorter than 530 nm are liable to cause characteristic deterioration due to ultraviolet irradiation and lack long-term stability. In this embodiment, an embodiment of an organic recording material suitable for use in the vicinity of 405 nm will be described. However, it is stable in the range of 355 to 455 nm in consideration of fluctuations in emission wavelength by the manufacturer of the semiconductor laser light source. Embodiments relating to organic recording materials that can be used in the present invention will be described. That is, the adaptive range of the present embodiment corresponds to a light source suitable for a light source of 620 nm or less, desirably light shorter than 530 nm (range of 355 to 455 nm in the narrowest range definition).

  Further, the optical recording sensitivity due to the light absorption spectrum of the organic dye material is greatly affected by the recording wavelength. Organic dye materials suitable for long-term stability generally tend to have a low absorbance for light having a short wavelength. In particular, the absorbance is significantly reduced for light shorter than 620 nm, and is drastically decreased particularly for light shorter than 530 nm. Therefore, when recording with a laser beam in the range of 355 to 455 nm as the most severe condition, the recording sensitivity is poor due to the low absorbance, and a new idea to adopt a new recording principle as shown in this embodiment is necessary. It becomes.

  The size of the focused spot used for recording or reproduction becomes smaller in proportion to the wavelength of light used. Therefore, considering only from the viewpoint of the focused spot size, if the wavelength is shortened to the above-mentioned value, the track pitch and channel bit length are increased by the wavelength of the current DVD-R disc (use wavelength: 650 nm), which is a conventional technology. I want to shorten it. However, as will be described later in “3-2-A] The scope of application of the technology of this embodiment”, the track pitch is used as long as the recording principle of a conventional write-once information storage medium such as a DVD-R disk is used. There is a problem that the channel bit length cannot be shortened. The track pitch and channel bit length can be shortened in proportion to the wavelength described above for the first time by using the technique devised in the present embodiment described below.

Chapter 1 Explanation of Combinations of Information Storage Medium Components in the Present Embodiment In this embodiment, an organic recording material (organic dye material) suitable for a light source of 620 nm or less has a great technical feature. The material (organic dye material) has a unique characteristic (low to high characteristic) that does not exist in conventional CD-R discs and DVD-R discs, in which the light reflectance increases within the recording mark. Therefore, the technical features of the present embodiment can be obtained by combining the structure, dimensions, or format (information recording format) of the information storage medium that makes more effective use of the characteristics of the organic recording material (organic dye material) shown in the present embodiment. Features and new effects are generated. Table 1 shows combinations that produce new technical features and effects in the present embodiment. That is, in the information storage medium in this embodiment, the constituent elements are: A] an organic dye recording film,
B] Preformat (pregroove shape / dimension, prepit shape / dimension, etc.),
C] Wobble conditions (wobble modulation method, wobble change shape, wobble amplitude, wobble placement method, etc.)
D] format (recording on the information storage medium / recording format of pre-recorded data, etc.), etc., and specific embodiments for each component are described in each column of Table 1. . The technical features and unique effects of the present embodiment are generated in the combination of the specific embodiments for each component shown in Table 1. In the following description of the embodiments, the combined state of the individual embodiments will be described. Regarding components that do not particularly specify the combination, A5) any coated recording film,
B3) Arbitrary groove shape and arbitrary pit shape,
C4) Arbitrary modulation method,
C6) an arbitrary amplitude amount;
D4) This means that any additional recording method and format are adopted.

Chapter 2 Explanation of Differences in Reproduced Signal between Phase Change Recording Film and Organic Dye Recording Film 2-1) Difference in Recording Principle / Recording Film Structure and Difference in Basic Concept for Generating Reproduced Signal Standard in FIG. Shows a typical phase change recording film structure (mainly used for a rewritable information storage medium). FIG. 1B shows a standard organic dye recording film structure (mainly used for a write-once information storage medium). Show). In the description of the present embodiment, the entire recording film structure (including the light reflection layers 4-1 and 4-2) excluding the transparent substrates 2-1 and 2-2 shown in FIG. It is defined and distinguished from the single recording layer 3-1 and 3-2 in which the recording material is arranged. In recording materials that use phase change, the amount of change in optical characteristics between recorded areas (inside recorded marks) and unrecorded areas (outside recorded marks) is generally small. An enhanced structure is used. Therefore, in the phase change recording film structure, as shown in FIG. 1A, the base intermediate layer 5 is disposed between the transparent substrate 2-1 and the phase change recording layer 3-1, and the phase of the light reflecting layer 4-2 and the phase change recording layer 3-1. The upper intermediate layer 6 is disposed between the changeable recording layer 3-1. In this embodiment, polycarbonate PC or acrylic PMMA (polymethyl methacrylate), which is a transparent plastic material, is employed as the material for the transparent substrates 2-1 and 2-2. The center wavelength of the laser beam 7 used in this embodiment is 405 nm, and the refractive indexes n21 and n22 of the polycarbonate PC at this wavelength are in the vicinity of 1.62. The standard refractive index n31 and absorption coefficient k31 at 405 nm in GeSbTe (germanium antimony tellurium), which is most commonly used as a phase change recording material, are n31≈1.5 and k31≈2. In contrast, n31≈2.5 and k31≈1.8 in the amorphous region. Thus, the refractive index (in the amorphous region) of the phase change recording material is significantly different from the refractive index of the transparent substrate 2-1, and in the phase change recording film structure, the reflection of the laser beam 7 at the interface of each layer is performed. It is easy to happen. As described above, (1) the phase change recording film structure has an enhanced structure, and (2) the difference in refractive index between the layers is large. Changes in the amount of reflected light during reproduction (the difference between the reflected light amount from the recording mark and the reflected light amount from the unrecorded area) are the base intermediate layer 5, the recording layer 3-1, the upper intermediate layer 6, and the light reflective layer 4- It is obtained as a result of interference of multiple reflected light generated at each of the two interfaces. In FIG. 1 (a), the laser beam 7 is emitted from the interface between the base intermediate layer 5 and the recording layer 3-1, the interface between the recording layer 3-1 and the upper intermediate layer 6, the upper intermediate layer 6 and the light reflecting layer. Although it appears that the light is reflected only at the interface with 4-2, the light reflected light amount change is actually obtained as a result of the interference between multiple reflected lights.

  On the other hand, the organic dye recording film structure has a very simple laminated structure of only the organic dye recording layer 3-2 and the light reflecting layer 4-2. An information storage medium (optical disk) using this organic dye recording film is called a write-once information storage medium and can be recorded only once, but it is like a rewritable information storage medium using the phase change recording film. It is not possible to erase or rewrite information once recorded. The refractive index at 405 nm of a general organic dye recording material is n32≈1.4 (the refractive index range at 405 nm of various organic dye recording materials is n32 = 1.4 to 1.9), and the absorption coefficient k32≈ There are many in the vicinity of 0.2 (the absorption coefficient range at 405 nm of various organic dye recording materials is also k32≈0.1 to 0.2). Since the refractive index difference between the organic dye recording material and the transparent substrate 2-2 is small, the amount of light reflection at the interface between the recording layer 3-2 and the transparent substrate 2-2 hardly occurs. Therefore, the principle of optical reproduction from the organic dye recording film (the reason why the reflected light amount changes) is not “multiple interference” in the phase change recording film as described above, but “reflected by the light reflection layer 4-2”. The main factor is the “light loss in the middle of the optical path (including interference)” with respect to the returning laser beam 7. Specific reasons for causing the light quantity loss in the middle of the optical path include “interference phenomenon due to phase difference partially caused in the laser light 7” and “light absorption phenomenon in the recording layer 3-2”. The light reflectance of the organic dye recording film in the unrecorded area on the mirror surface without pregroove or prepit is the light when passing through the recording layer 3-2 from the light reflectance of the laser beam 7 in the light reflecting layer 4-2. It is characterized in that it can be obtained simply by subtracting the amount of absorption. As described above, there is a great difference from the phase change recording film in which the light reflectance is obtained by calculating “multiple interference”.

First, a description will be given of a recording principle that is interpreted as a conventional technique in the current DVD-R disc. In the current DVD-R disc, when the recording film is irradiated with the laser beam 7, the recording layer 3-2 locally absorbs the energy of the laser beam 7 and becomes hot. When the specific temperature is exceeded, the transparent substrate 2-2 is locally deformed. The mechanism for inducing the deformation of the transparent substrate 2-2 differs depending on the DVD-R disc manufacturer.
(1) The transparent substrate 2-2 is locally plastically deformed by the vaporization energy of the recording layer 3-2. (2) Heat is transferred from the recording layer 3-2 to the transparent substrate 2-2, and locally transparent by the heat. It is said that the substrate 2-2 is caused by plastic deformation. When the transparent substrate 2-2 is locally plastically deformed, it is reflected by the light reflecting layer 4-2 through the transparent substrate 2-2, and then returns to the optical path of the laser light 7 that passes through the transparent substrate 2-2 again. The target distance changes. The laser beam 7 from the recording mark returning through the part of the transparent substrate 2-2 locally plastically deformed, and the recording mark returning through the part of the transparent substrate 2-2 not deformed Since there is a phase difference with the laser beam 7 from the peripheral portion, the amount of reflected light changes due to interference between the two companies. In particular, when the mechanism (1) occurs, a substantial change in the refractive index n32 caused by cavitation of the recording mark of the recording layer 3-2 due to vaporization (evaporation), or within the recording mark. The change in the refractive index n32 caused by the thermal decomposition of the organic dye recording material contributes to the generation of the phase difference. In the current DVD-R disc, the recording layer 3-2 remains at a high temperature until the transparent substrate 2-2 is locally deformed (the vaporization temperature of the recording layer 3-2 in the mechanism (1) above, and transparent in the mechanism (2) above). The temperature inside the recording layer 3-2 required for plastic deformation of the substrate 2-2) or a high temperature is necessary to thermally decompose or vaporize (evaporate) a part of the recording layer 3-2. In order to form a recording mark, a large power of the laser beam 7 is required.

  In order to form a recording mark, it is necessary that the recording layer 3-2 can absorb the energy of the laser beam 7 as a first step. The light absorption spectrum in the recording layer 3-2 greatly affects the recording sensitivity of the organic dye recording film. The principle of light absorption in the organic dye recording material forming the recording layer 3-2 will be described with reference to (A3) of the present embodiment.

  Chemical formula 1 shows a specific structural formula of the specific content “(A3) azo metal complex + Cu” of the constituent elements of the information storage medium shown in FIG.

  A circular peripheral region centering on the central metal M of the azo metal complex shown in Chemical Formula 1 is the color developing region 8. When the laser beam 7 passes through the coloring region 8, the localized electrons in the coloring region 8 resonate with the electric field change of the laser beam 7 and absorb the energy of the laser beam 7. The value converted to the wavelength of the laser beam 7 with respect to the frequency of the electric field change at which the localized electrons resonate most easily and absorb energy is called the maximum absorption wavelength and is represented by λmax. As the length of the color development region 8 (resonance range) as shown in Chemical Formula 1 increases, the maximum absorption wavelength λmax shifts to the longer wavelength side. In addition, by changing the atom of the central metal M in the chemical formula 1, the localized range of localized electrons around the central metal M (how much the central metal M can attract the localized electrons to the center) changes, and the maximum absorption. The value of the wavelength λmax changes.

It is expected that the light absorption spectrum of the organic dye recording material in the case of absolute zero, high purity, and only one color developing region 8 will draw a narrow line spectrum near the maximum absorption wavelength λmax. In addition, the light absorption spectrum of a general organic dye recording material including a plurality of light absorption regions shows a broad absorption characteristic with respect to the wavelength of light centered on the maximum absorption wavelength λmax. An example of the light absorption spectrum of the organic dye recording material used in the current DVD-R disc is shown in FIG. In FIG. 2, the horizontal axis represents the wavelength of light applied to the organic dye recording film formed by coating the organic dye recording material, and the vertical axis represents the absorbance when the organic dye recording film is irradiated with light of each wavelength. Is taken. Absorbance refers to a state completed as a write-once information storage medium (or a state where only the recording layer 3-2 is formed on the transparent substrate 2-2 (the light reflecting layer 4-2 with respect to the structure of FIG. 1B). The laser light having the incident intensity Io is incident from the transparent substrate 2-2 side to the reflected laser light intensity Ir (the light intensity of the laser light transmitted from the recording layer 3-2 side). It is a value obtained by measuring It). Absorbance Ar (At) is Ar≡-log10 (Ir / Io) (A-1)
At≡-log10 (It / Io) (A-2)
It is represented by As long as there is no notice in the future, the absorbance will be described by showing the reflection type absorbance Ar expressed by the equation (A-1), but in the present embodiment, it is not limited to this and expressed by the equation (A-2). It can also be considered as the transmission type absorbance At. In the embodiment shown in FIG. 2, there are a plurality of light absorption regions including the color development region 8, and therefore there are a plurality of positions where the absorbance is maximized. In this case, there are a plurality of maximum absorption wavelengths λmax when the absorbance takes a maximum value. The wavelength of the recording laser beam in the current DVD-R disc is 650 nm. In the present embodiment, when there are a plurality of maximum absorption wavelengths λmax, the value of the maximum absorption wavelength λmax closest to the wavelength of the recording laser beam becomes important. Therefore, only in the description of the present embodiment, the value of the maximum absorption wavelength λmax that is closest to the wavelength of the recording laser beam is defined as “λmax write” and is distinguished from other λmax (λmax 0).

2-2) Difference in Light Reflecting Layer Shape in Prepit / Pregroove Region FIG. 3 shows a comparison of the formation shape of the recording film in the prepit region or the pregroove region 10. FIG. 3A shows the shape of the phase change recording film. When forming any of the base intermediate layer 5, the recording layer 3-1, the upper intermediate layer 6, and the light reflecting layer 4-1, any one of sputter vapor deposition, vacuum vapor deposition, or ion plating is used in vacuum. . As a result, the uneven shape of the transparent substrate 2-1 is replicated relatively faithfully in all layers. For example, when the cross-sectional shape in the pre-pit region or pre-groove region 10 of the transparent substrate 2-1 is rectangular or trapezoidal, the cross-sectional shapes of the recording layer 3-1 and the light reflecting layer 4-1 are also approximately rectangular or It becomes a trapezoid.

  FIG. 3B shows a general recording film cross-sectional shape of a current DVD-R disc which is a conventional technique as a recording film when an organic dye recording film is used. As a method for forming the recording film 3-2 in this case, a completely different method called spin coating (or spinner coding) is used unlike FIG. In spin coating, the organic dye recording material for forming the recording layer 3-2 is dissolved in an organic solvent and applied onto the transparent substrate 2-2, and then the transparent substrate 2-2 is rotated at high speed to apply the coating agent by centrifugal force. In this method, the recording layer 3-2 is formed by spreading to the outer peripheral side of the transparent substrate 2-2 and vaporizing an organic solvent. When this method is used, an organic solvent coating step is used, so that the surface of the recording layer 3-2 (interface with the light reflection layer 2-2) tends to be flat. As a result, the cross-sectional shape at the interface between the light reflecting layer 2-2 and the recording layer 3-2 is the surface shape of the transparent substrate 2-2 (interface between the transparent substrate 2-2 and the recording layer 3-2). Have different shapes. For example, in the pregroove region where the cross-sectional shape of the surface of the transparent substrate 2-2 (interface between the transparent substrate 2-2 and the recording layer 3-2) is a rectangle or a trapezoid, the light reflecting layer 2-2 and the recording layer 3 are used. -2 has a substantially V-shaped groove shape at the interface, and a substantially conical side surface shape in the prepit region. Furthermore, since the organic solvent tends to accumulate in the recess during spin coating, the thickness Dg of the recording layer 3-2 in the prepit region or pregroove region 10 (as shown in FIG. 3B), the prepit region or pregroove region 10 The distance from the bottom surface to the lowest position of the interface with the light reflection layer 2-2) is significantly larger than the thickness Dl in the land region 12 (Dg> Dl). As a result, the unevenness amount at the interface between the transparent substrate 2-2 and the recording layer 3-2 in the prepit region or the pregroove region 10 is significantly larger than the unevenness amount at the interface between the transparent substrate 2-2 and the recording layer 3-2. It has become less.

As described above, the uneven shape at the interface between the light reflecting layer 2-2 and the recording layer 3-2 is dull and the uneven amount is greatly reduced. Therefore, the surface of the transparent substrate 2 (pre-pit region) is different depending on the recording film forming method. Alternatively, when the concave and convex shapes and dimensions of the pregroove region 10) are the same, the diffraction intensity of the reflected light from the organic dye recording film when irradiated with the laser light is significantly greater than the diffraction intensity of the reflected light from the phase change recording film. to degrade. As a result, when the surface of the transparent substrate 2 (pre-pit region or pre-groove region 10) has the same concavo-convex shape and dimensions, the conventional organic dye recording film is used in comparison with the phase change recording film. (1) The degree of modulation of the optical reproduction signal from the prepit area is small and the signal reproduction reliability from the prepit area is poor (2) A sufficiently large track deviation detection signal from the pregroove area by the push-pull method is difficult to obtain (3) There is a feature that it is difficult to obtain a sufficiently large wobble detection signal when the pregroove area is wobbling (meandering).

  Further, in the DVD-R disc, specific information such as address information is recorded in the land area 12 in a minute unevenness (pit) shape, so that the width Wl of the land area 12 is larger than the width Wg of the prepit area or the pregroove area 10. Is wide (Wg> Wl).

Chapter 3 Description of Features of Organic Dye Recording Film in Present Embodiment 3-1) Problems with High Density in Additional Recording Film (DVD-R) Using Conventional Organic Dye Material “2-1) Recording Principle / As already explained in “Differences in recording film structure and fundamental differences in reproduction signal generation”, the conventional DVD-R and CD-R that are write-once information storage media using conventional organic dye materials are generally used. A typical recording principle is accompanied by “local plastic deformation of the transparent substrate 2-2” or “local thermal decomposition and vaporization in the recording layer 3-2”. FIG. 4 shows a specific plastic deformation state of the transparent substrate 2-2 at the recording mark 9 position in the recordable information storage medium using the conventional organic dye material. There are two types of typical plastic deformation situations, and as shown in FIG. 4A, the depth of the bottom surface 14 of the pre-groove area at the position of the recording mark 9 (the amount of step between the adjacent land areas 12) is. When the depth is different from the depth of the bottom surface of the pre-groove area 11 in the unrecorded area (in the example shown in FIG. 4A), the depth of the bottom surface 14 of the pre-groove area at the position of the recording mark 9 is shallower than the unrecorded area. 4), as shown in FIG. 4B, the bottom surface 14 of the pre-groove region at the position of the recording mark 9 is slightly distorted (the flatness of the bottom surface 14 is broken: the example shown in FIG. 4B) In this case, the bottom surface 14 of the pre-groove area at the position of the recording mark 9 is slightly curved downward). In either case, there is a feature that the plastic deformation range of the transparent substrate 2-2 at the position of the recording mark 9 extends over a wide region. The current DVD-R disc, which is a conventional technology, has a track pitch of 0.74 μm and a channel bit length of 0.133 μm. In the case of such a large value, a relatively stable recording process and reproducing process can be performed even when the plastic deformation range of the transparent substrate 2-2 at the position of the recording mark 9 is wide.

  However. If the track pitch is made narrower than the above 0.74 μm, the plastic deformation range of the transparent substrate 2-2 at the position of the recording mark 9 extends to a wide area, so that an adverse effect on the adjacent track appears, and the recording mark reaches the adjacent track. The phenomenon of “cross erase” occurs in which the recording mark 9 of the adjacent track that already exists due to multiple writing is substantially erased (made unreproducible). In addition, if the channel bit length in the direction along the track (circumferential direction) is narrower than 0.133 μm, intersymbol interference appears, and the error rate during reproduction greatly increases and the reproduction reliability decreases. Will occur.

3-2) Basic characteristics common to the organic dye recording film in the present embodiment 3-2-A] Range that requires application of the technique of the present embodiment Plasticity of the transparent substrate 2-2 as shown in FIG. How much the track pitch is reduced in a conventional write-once information storage medium (CD-R or DVD-R) with deformation or local thermal decomposition or vaporization phenomenon in the recording layer 3-2, or which is adversely affected The following will describe the result of a technical study on whether or not the adverse effect appears when the channel bit length is reduced to some extent. A range in which an adverse effect starts to occur when the conventional recording principle is used indicates a range in which the effect is exhibited by the novel recording principle shown in the present embodiment (suitable for high density).

(1) Conditions for the thickness Dg of the recording layer 3-2 If a thermal analysis is performed to theoretically determine the lower limit value of the allowable channel bit length and the lower limit value of the allowable track pitch, the recording layer 3- The range of the thickness Dg of 2 is important. In the conventional write-once information storage medium (CD-R or DVD-R) with plastic deformation of the transparent substrate 2-2 as shown in FIG. The change in the amount of light reflection when it is in the unrecorded area of the recording layer 3-2 has the largest factor of "interference effect due to the difference in optical distance between the recorded mark 9 and the unrecorded area". The difference in the optical distance is mainly “the thickness Dg of the physical recording layer 3-2 due to plastic deformation of the transparent substrate 2-2 (from the interface between the transparent substrate 2-2 and the recording layer 3-2 to the recording layer 3). −2 and the physical distance to the interface between the light reflecting layer 4-2 ”and“ change in the refractive index n32 of the recording layer 3-2 within the recording mark 9 ”. Therefore, in order to obtain a sufficient reproduction signal (change in the amount of reflected light) between the recorded mark 9 and the unrecorded area, when the wavelength of the laser beam in vacuum is λ, The value of the thickness Dg of the recording layer 3-2 needs to have a certain size as compared with λ / n32. Otherwise, the difference in optical distance (phase difference) between the recorded mark 9 and the unrecorded area does not appear, and the light interference effect becomes thin. Actually at least Dg ≧ λ / 8n32 (1)
Desirably Dg ≧ λ / 4n32 (2)
These conditions are required.

For the time being, it is assumed that λ = 405 nm. The value of the refractive index n32 of the organic dye recording material at 405 nm is generally in the range of 1.3 to 2.0. Accordingly, as a value of the thickness Dg of the recording layer 3-2, n32 = 2.0 is substituted into the equation (1),
Dg ≧ 25 nm (3)
Is an essential condition. Here, the conditions when the organic dye recording layer of a conventional write-once information storage medium (CD-R or DVD-R) with plastic deformation of the transparent substrate 2-2 is made to correspond to 405 nm light are examined. ing. As will be described later, in this embodiment, the change of the absorption coefficient k32 will be described as a main factor of the recording principle without causing plastic deformation of the transparent substrate 2-2. Since it is necessary to detect the track deviation, the refractive index n32 is actually changed in the recording mark 9. Therefore, the condition of the formula (3) is a condition that should be satisfied even in the present embodiment in which the transparent substrate 2-2 does not undergo plastic deformation.

From another viewpoint, the range of the thickness Dg of the recording layer 3-2 can be specified. In the case of the phase change recording film shown in FIG. 3 (a), when the refractive index of the transparent substrate is n21, the push-pull method is used to produce the largest track deviation detection signal between the prepit area and the land area. The step amount is λ / (8n21). However, in the case of the organic dye recording film shown in FIG. 3B, as described above, the shape at the interface between the recording layer 3-2 and the light reflecting layer 4-2 becomes dull and the level difference becomes small. The level difference between the prepit area and the land area on the substrate 2-2 needs to be larger than λ / (8n22). For example, when polycarbonate is used as the material of the transparent substrate 2-2, the refractive index at 405 nm is n22≈1.62. Therefore, the step amount between the prepit area and the land area needs to be larger than 31 nm. When the spin coating method is used, the recording layer 3 in the land area 12 must be formed unless the thickness Dg of the recording layer 3-2 in the pregroove area is larger than the step amount between the prepit area and the land area on the transparent substrate 2-2. There is a risk that the thickness Dl of -2 is lost. Therefore, from the above examination results, Dg ≧ 31 nm (4)
It is necessary to satisfy the condition. The condition of equation (4) is also a condition that should be satisfied in the present embodiment in which the transparent substrate 2-2 does not undergo plastic deformation. Although the conditions of the lower limit value are shown by the expressions (3) and (4), n32 = 1.8 is substituted for the equal sign part of the expression (2) as the thickness Dg of the recording layer 3-2 used in the thermal analysis. The value Dg≈60 nm obtained was used.

  Then, assuming that polycarbonate is used as a standard material for the transparent substrate 2-2, 150 ° C., which is a glass transition temperature of polycarbonate, is set as an estimated value of the thermal deformation temperature on the transparent substrate 2-2 side. In the examination using thermal analysis, a value of k32 = 0.1 to 0.2 was assumed as the value of the absorption coefficient of the organic dye recording film 3-2 at 405 nm. Furthermore, the NA value of the focusing objective lens and the incident light intensity distribution when passing through the objective lens are NA = 0.60 and H format (FIG. 1 (D1): NA =), which are preconditions for the conventional DVD-R format. 0.65) and B format (FIG. 1 (D2): NA = 0.85).

(2) Channel bit length lower limit condition When the recording power is changed, the length change in the direction along the track of the region reaching the thermal deformation temperature on the transparent substrate 2-2 side in contact with the recording layer 3-2 We examined the lower limit of the allowable channel bit length considering the window margin during playback. As a result, if the channel bit length is made smaller than 105 nm, the length change in the direction along the track in the region reaching the thermal deformation temperature on the transparent substrate 2-2 side according to a slight change in the recording power occurs. Wind margin is not considered. In the study of thermal analysis, similar values are shown for NA values of 0.60, 0.65, and 0.85. Although the condensing spot size changes by changing the NA value, it is considered that the heat spread range is wide (the gradient of the temperature distribution on the transparent substrate 2-2 side in contact with the recording layer 3-2 is relatively gentle). It is done. In the thermal analysis, since the temperature distribution on the transparent substrate 2-2 side in contact with the recording layer 3-2 is examined, the influence of the thickness Dg of the recording layer 3-2 does not appear.

  Further, when the shape change of the transparent substrate 2-2 shown in FIG. 4 occurs, the boundary position of the substrate deformation region is blurred (unclear), and the window margin is further reduced. When the cross-sectional shape of the region where the recording mark 9 is formed is observed with an electron microscope, it is considered that the amount of blur at the boundary position of the substrate deformation region increases as the value of the thickness Dg of the recording layer 3-2 increases. In consideration of the blur of the boundary position of the substrate deformation region in consideration of the influence of the heat deformation region length due to the change in the recording power, the lower limit value of the allowable channel bit length for securing a sufficient window margin is the recording layer 3-2. It is considered that about twice the thickness Dg is necessary, and it is desirable that the thickness is larger than 120 nm.

  In the above, the examination by the thermal analysis when the thermal deformation of the transparent substrate 2-2 occurs is mainly described. As another recording principle (mechanism for forming the recording mark 9) in the conventional write-once information storage medium (CD-R or DVD-R), the plastic deformation of the transparent substrate 2-2 is very little and the recording layer 3-2 There are cases where the thermal decomposition and vaporization (evaporation) of the organic dye recording material is the center. The vaporization (evaporation) temperature of the organic dye recording material varies depending on the organic dye material, but is generally in the range of 220 ° C. to 370 ° C., and the thermal decomposition temperature is lower. In the above examination, the glass transition temperature of the polycarbonate resin is assumed to be 150 ° C. as the temperature at the time of substrate deformation, but the temperature difference between 150 ° C. and 220 ° C. is small, and when the transparent substrate 2-2 reaches 150 ° C. It exceeds 220 ° C. inside the recording layer 3-2. Therefore, although there are exceptions due to the organic dye recording material, even if the plastic deformation of the transparent substrate 2-2 is very small, the thermal decomposition or vaporization (evaporation) of the organic dye recording material in the recording layer 3-2 is the main. The result is almost the same as the above examination result.

  Summarizing the results of the study on the channel bit length, in the conventional write-once information storage media (CD-R and DVD-R) with plastic deformation of the transparent substrate 2-2, the window margin is reduced when the channel bit length is made smaller than 120 nm. It is thought that stable reproduction becomes difficult when the thickness is smaller than 105 nm. That is, when the channel bit is smaller than 120 nm (105 nm), the effect of using the new recording principle shown in this embodiment is exhibited.

(3) Lower limit condition of track pitch When the recording layer 3-2 is exposed with recording power, energy is absorbed in the recording layer 3-2 and the temperature becomes high. In a conventional write-once information storage medium (CD-R or DVD-R), it is necessary to absorb energy in the recording layer 3-2 until the transparent substrate 2-2 reaches the heat distortion temperature. The temperature at which the structural change of the organic dye recording material occurs in the recording layer 3-2 and the values of the refractive index n32 and the absorption coefficient k32 start changing is much higher than the temperature at which the transparent substrate 2-2 starts thermal deformation. Very low. Accordingly, the refractive index n32 and the absorption coefficient k32 change in a relatively wide area in the recording layer 3-2 around the recording mark 9 where the transparent substrate 2-2 is thermally deformed. It seems to be the cause of “cross light” and “cross erase”. “Cross light” or “Cross erase” depending on the size of the region reaching the temperature for changing the refractive index n32 and the absorption coefficient k32 in the recording layer 3-2 when the transparent substrate 2-2 side exceeds the thermal deformation temperature. You can set the lower limit of the track pitch that does not cause From the above viewpoint, it is considered that “cross light” and “cross erase” occur when the track pitch is 500 nm or less. Further, in consideration of the influence of the warp and tilt of the information storage medium and the change in recording power (recording power margin), the conventional energy absorption is performed in the recording layer 3-2 until the transparent substrate 2-2 reaches the thermal deformation temperature. It can be concluded that it is difficult to make the track pitch 600 nm or less in the recordable information storage medium (CD-R or DVD-R). As described above, even if the NA value is changed to 0.60, 0.65, and 0.85, in the recording layer 3-2 around the center when the transparent substrate 2-2 reaches the thermal deformation temperature. The gradient of the temperature distribution is relatively gentle and the heat spread range is wide, so the same tendency is shown. As another recording principle (mechanism for forming the recording mark 9) in the conventional write-once information storage medium (CD-R or DVD-R), the plastic deformation of the transparent substrate 2-2 is very little and the recording layer 3-2 Even when the thermal decomposition and vaporization (evaporation) of organic dye recording materials at the center is, the “cross light” and “cross erase” are already described in “(2) Lower limit condition of channel bit length”. The starting track pitch values give almost similar results. For the above reasons, the effect of using the new recording principle shown in the present embodiment is exhibited when the track pitch is 600 nm (500 nm) or less.

3-2-B] Basic features common to the organic dye recording material in this embodiment As described above, the recording principle (formation of the recording mark 9) in the conventional write-once information storage medium (CD-R or DVD-R) When the transparent substrate 2-2 is accompanied by plastic deformation as a mechanism) or when local thermal decomposition or vaporization (evaporation) occurs in the recording layer 3-2, the recording layer 3-2 is formed when the recording mark 9 is formed. Since the inside and the surface of the transparent substrate 2-2 reach a high temperature, there arises a problem that the channel bit length and the track pitch cannot be reduced. As a solution to the above problem, the present embodiment does not cause substrate deformation or vaporization (evaporation) in the recording layer 3-2. “Local optical characteristic change in the recording layer 3-2 that occurs at a relatively low temperature” Is characterized by the fact that “the invention of the organic dye material” and “setting of the environment (recording film structure and shape)” in which the above recording principle is likely to occur are performed. The following contents can be raised as specific features of the present embodiment.

[alpha]] As a method of changing the optical characteristics inside the recording layer 3-2-Change in color development characteristics-Change in light absorption cross section and change in molar absorption coefficient due to qualitative change in color development area 8
The light absorption spectrum (FIG. 2) profile (characteristics) itself is preserved by maintaining the light absorption spectrum (FIG. 2) by partially destroying the color development region 8 or changing the substantial light absorption cross section by changing the size of the color development region 8. The amplitude (absorbance) at the write position changes in the recording mark 9-Changes in the electronic structure (electron orbital) for electrons contributing to the color development phenomenon ... by local electron orbital breakage (local molecular bond dissociation) Change in optical absorption spectrum (Fig. 2) based on decoloring action and changes in size and structure of color development region 8 (Chemical formula 1)-Intramolecular (or intermolecular) orientation and sequence changes ... For example, azo shown in Chemical formula 1 Changes in optical properties based on orientation changes inside the metal complex-Changes in molecular structure inside the molecule ... For example, bond dissociation between the anion part and the cation part, or heat of either the anion part or the cation part Solution, or molecular structure itself is destroyed, to devise an organic dye material which causes either a tar phenomenon that atoms (which transformed into coal tar black). As a result, the optical index can be reproduced by changing the refractive index n32 and the absorption coefficient k32 in the recording mark 9 with respect to the unrecorded area.

[beta]] The recording film structure and shape that are likely to cause the change in the optical characteristics of [[alpha]] are set stably. For specific contents regarding this technique, "3-2-C", the recording principle shown in the present embodiment is generated. This will be described in detail after the “ideal recording film structure that can be easily formed”.

[gamma]] The recording power is lowered in order to form a recording mark in a state where the recording layer and the transparent substrate surface are at a relatively low temperature. -2 occurs at a temperature below the vaporization (evaporation) temperature in -2. Therefore, the exposure amount (recording power) at the time of recording is lowered to prevent the deformation temperature from being exceeded on the surface of the transparent substrate 2-2 and the vaporization (evaporation) temperature from being exceeded in the recording layer 3-2. This content will be described in detail later in “3-3) Recording characteristics common to the organic dye recording film in the present embodiment”. Conversely, by examining the value of the optimum power during recording, it is possible to determine whether or not the optical characteristic change indicated by [α] has occurred.

δ] Stabilizes the electronic structure in the color development region and makes it difficult to cause structural decomposition due to irradiation with ultraviolet rays or reproduction light. Irradiation of the recording layer 3-2 with ultraviolet rays or reproduction light during reproduction is performed on the recording layer 3-2. , The temperature in the recording layer 3-2 rises. In addition to preventing the deterioration of the characteristics due to the temperature rise, seemingly contradictory performance is required in terms of the temperature characteristics of recording at a temperature lower than the substrate deformation temperature and the vaporization (evaporation) temperature in the recording layer 3-2. In the present embodiment, the seemingly contradictory performance is ensured by “stabilizing the electronic structure in the coloring region”. The specific technical contents will be described in “Chapter 4 Description of Specific Embodiment of Organic Dye Recording Film in Present Embodiment”.

[epsilon]] Improves the reliability of the reproduction information in case the reproduction signal deteriorates due to the irradiation of ultraviolet rays or reproduction light. In this embodiment, the technical device for "stabilizing the electronic structure in the coloring region" However, when compared with a local cavity in the recording layer 3-2 generated by plastic deformation or vaporization (evaporation) on the surface of the transparent substrate 2-2, the recording formed by the recording principle shown in the present embodiment is performed. It must be said that the reliability of the mark 9 is reduced in principle. As a countermeasure, in the present embodiment, as described later in “Chapter 7 Explanation of H Format” and “Chapter 8 Explanation of B Format”, the density is increased by combining with a powerful error correction capability (new ECC block structure). And the reliability of recording information is achieved at the same time. Further, in the present embodiment, as described in “4-2) Description of the reproduction circuit in the present embodiment, a PRML (Pertial Response Maximum Likelyhood) method is adopted as a reproduction method, which is combined with an error correction technique at the time of ML demodulation. As a result, it is possible to achieve higher density and ensure the reliability of recorded information at the same time.

Among the specific features of the present embodiment, [α] to [γ] are technically devised in this embodiment in order to realize “narrow track pitch” and “narrow channel bit length”. I already explained that it was a devised content. In addition, “narrow channel bit lengthening” also leads to “reduction of minimum recording mark length”. The meaning (purpose) of the present embodiment regarding the remaining [δ] and [ε] will be described in detail. In the present embodiment, the passing speed (linear velocity) of the focused spot passing through the recording layer 3-2 during reproduction in the H format is set to 6.61 m / s, and the linear velocity in the B format is 5.0 to 10. Set in the range of 2 m / s. In any case, the linear velocity during reproduction in this embodiment is 5 m / s or more. As shown in FIG. 22, the start position of the data lead-in area DTLDI in the H format is 47.6 mm in diameter, and user data is recorded at a diameter of 45 mm or more even when the B format is taken into view. Since the circumference with a diameter of 45 mm is 0.141 m, the number of rotations of the information storage medium when reproducing this position at a linear velocity of 5 m / s is 35.4 rotations / s. One method of using the write-once information storage medium of this embodiment is video information recording such as TV programs. For example, when the user presses a “pause (pause) button” during playback of a video recorded by the user, the reproduction focused spot remains on the track at the pause position. If it is stopped on the track at the pause position, playback can be started from the position where the user paused immediately after pressing the “play start button”. For example, if a visitor arrives immediately after the user presses the “pause (pause) button” to get up, he may be left with the pause button pressed for 1 hour. The write-once information storage medium has rotated 35.4 × 60 × 60≈130,000 revolutions in one hour, and the focused spot traces on the same track all the time (repeatedly reproduced 130,000 times). If the recording layer 3-2 deteriorates repeatedly during that time and playback of the video information becomes impossible, the user who came back one hour later can not see a part of the video. Is at risk of becoming a trial. Therefore, it is necessary to guarantee that even if the recorded video information is not destroyed even if it is left for about one hour (continuous reproduction in the same track), it does not deteriorate even if it is repeatedly reproduced at least 100,000 times. As a general user use situation, it is rare to repeat the pause (repeat playback) for one hour for the same place 10 times. Therefore, as long as the repetitive reproduction of 1 million times is desirably ensured as the recordable information storage medium of the present embodiment, there is no problem for general user use, and the upper limit of the number of repetitive reproductions that does not deteriorate the recording layer 3-2. It is considered sufficient to set the value to about 1 million times. If the upper limit value of the number of repeated playbacks is set to a value that greatly exceeds one million times, inconveniences such as “the recording sensitivity is lowered” and “the medium price is raised” occur.

When the upper limit value of the number of repeated reproductions is guaranteed, the reproduction power value is an important factor. In the present embodiment, the recording power is defined within a range set by equations (8) to (13) described later. As a characteristic of a semiconductor laser, it is said that continuous light emission is not stable at a value of 1/80 or less of the maximum use power. At the power of 1/80 of the maximum use power, light emission is finally started (the mode starts standing), so that it is easy to mode hop. Therefore, this light emission power generates “return light noise” in which the amount of light emission always fluctuates when the light reflected by the light reflection layer 4-2 of the information storage medium returns to the semiconductor laser light source. Therefore, in this embodiment, the value of the reproduction power is based on the value of 1/80 of the value described on the right side of the equation (12) or (13) [Optimum reproduction power]
> 0.19 × (0.65 / NA) 2 × (V / 6.6) (B-1)
[Optimum playback power]
> 0.19 × (0.65 / NA) 2 × (V / 6.6) 1/2 (B-2)
Is set.

  The optimum reproduction power value is limited by the dynamic range of the power monitor photodetector. Although not shown in the information recording / reproducing unit 141 of FIG. 9, there is an optical head for recording / reproducing. This optical head incorporates a photodetector for monitoring the light emission amount of the semiconductor laser light source. In the present embodiment, in order to improve the light emission accuracy of the reproduction power during reproduction, this light detector detects the amount of light emission and applies feedback to the amount of current supplied to the semiconductor laser light source during light emission. In order to reduce the price of the optical head, it is necessary to use a very inexpensive photodetector. In many cases, commercially available inexpensive photodetectors are molded with resin (the light detection portion is surrounded).

  As shown in “Chapter 0 Description of Relationship between Use Wavelength and This Embodiment”, the light source wavelength in this embodiment is 530 nm or less (particularly 455 nm or less). In the case of this wavelength region, the resin (mainly epoxy type) that molds the photodetection part deteriorates when it is irradiated with the above-mentioned wavelength light (discoloration to yellow or cracks (fine white streaks)). And the light detection characteristics are deteriorated. In particular, in the case of the write-once information storage medium shown in this embodiment, the pre-groove area 11 as shown in FIG. As a defocus detection method of the optical head, a photodetector is arranged at an image forming position (image forming magnification M is about 3 to 10 times) with respect to the information storage medium in order to remove the adverse effect due to the diffracted light from the pre-groove region 11. The “knife edge method” is most often used. When the photodetector is disposed at the image forming position, the light is condensed on the photodetector, so that the light density irradiated on the mold resin is increased, and the resin is easily deteriorated by the light irradiation. Although the characteristic deterioration of the mold resin is mainly caused by the photon mode (optical action), the upper limit value of the allowable irradiation amount can be predicted in comparison with the light irradiation amount in the thermal mode (thermal excitation). Assume an optical system in which a photodetector is arranged at an imaging position as an optical head assuming the worst state.

From the content described in “(1) Conditions for Thickness Dg of Recording Layer 3-2” within “3-2-A] Range of Application of Technology of Present Embodiment”, the recording layer at the time of recording in the present embodiment When an optical characteristic change (thermal mode) occurs in 3-2, it is considered that the temperature temporarily rises in the range of 80 ° C. to 150 ° C. in the recording layer 3-2. Assuming that the room temperature is around 15 ° C., the temperature difference ΔTwrite is 65 ° C. to 135 ° C. Since pulse emission is performed during recording but continuous emission is performed during reproduction, the temperature rises in the recording layer 3-2 during reproduction, and a temperature difference ΔTread occurs. If the imaging magnification of the detection system in the optical head is M, the light density of the detection light focused on the photodetector is 1 / M2 of the light density of the convergent light irradiated on the recording layer 3-2. Therefore, the amount of temperature rise on the photodetector during reproduction becomes ΔTread / M2 as a rough estimate. Considering that the mold resin deterioration occurs in the photon mode, it is considered that ΔTread / M2 ≦ 1 ° C. when the upper limit value of the light density that can be irradiated on the photodetector is converted by the temperature rise amount. Since the imaging magnification of the detection system in the optical head is generally about 3 to 10 times, assuming that M2≈10 temporarily,
ΔTread / ΔTwrite ≦ 20 (B-3)
It is necessary to set the reproduction power so that If the duty ratio of the recording pulse during recording is estimated to be 50%, [optimum reproduction power] ≦ [optimum recording power] / 10 (B-4)
Is required. Therefore, the optimum playback power is [Optimum playback power] taking into account formulas (8) to (13) and formula (B-4) described later.
<3 × (0.65 / NA) 2 × (V / 6.6) (B-5)
[Optimum playback power]
<3 × (0.65 / NA) 2 × (V / 6.6) 1/2 (B-6)
[Optimum playback power]
<2 × (0.65 / NA) 2 × (V / 6.6) (B-7)
[Optimum playback power]
<2 * (0.65 / NA) 2 * (V / 6.6) 1/2 (B-8)
[Optimum playback power]
<1.5 × (0.65 / NA) 2 × (V / 6.6) (B-9)
[Optimum playback power]
<1.5 × (0.65 / NA) 2 × (V / 6.6) 1/2 (B-10)
(Refer to “3-2-E] Basic characteristics regarding thickness distribution of recording layer in this embodiment” for the definition of each parameter.)
Given in. For example, when NA = 0.65 and V = 6.6 m / s, [optimum reproduction power] <3 mW,
[Optimum playback power] <2mW,
Or [optimum playback power] <1.5mW
It becomes. Actually, the optical detector is fixed as compared with the information storage medium that rotates and moves relatively, so that the optimum reproduction power is further taken into consideration by taking this into consideration. Must be less than or equal to In the information recording / reproducing apparatus in this embodiment, the value of the reproduction power is set to 0.4 mW.

3-2-C] Ideal recording film structure in which the recording principle shown in the present embodiment is easy to be generated In the present embodiment, regarding the “environment (recording film structure and shape) setting” method in which the recording principle is likely to occur. explain.

As an environment in which the optical characteristics inside the recording layer 3-2 described above are likely to change, “the temperature exceeding the critical temperature at which the optical characteristics change occurs in the recording mark 9 formation region and the vaporization (evaporation) temperature at the center of the recording mark 9 is set. The surface of the transparent substrate 2-2 near the center of the recording mark 9 does not exceed the thermal deformation temperature. ”
As described above, the technical features of the recording film structure and shape are as follows.

  Specific contents regarding the above will be described with reference to FIG. In FIG. 5, the hollow arrow indicates the optical path of the irradiation laser beam 7, and the broken arrow indicates the heat flow. The recording film structure shown in FIG. 5A shows an environment in which the optical characteristic change in the recording layer 3-2 corresponding to this embodiment is most likely to occur. That is, in FIG. 5A, the recording layer 3-2 made of an organic dye recording material has a uniform thickness throughout the range (sufficiently thick) in the range indicated by the formula (2) or (4). The laser beam 7 is irradiated from a direction perpendicular to -2. As will be described later in detail in “6-1) Light Reflecting Layer (Material and Thickness)”, in this embodiment, a silver alloy is used as the material of the light reflecting layer 4-2. A material including a metal having a high light reflectance, not limited to a silver alloy, generally has a high thermal conductivity and a heat dissipation characteristic. Therefore, the energy of the irradiated laser beam 7 is absorbed and the temperature of the recording layer 3-2 rises, but heat is released toward the light reflecting layer 4-2 having heat dissipation characteristics. Since the recording film shown in FIG. 5 (a) has a uniform shape everywhere, a relatively uniform temperature rise occurs inside the recording layer 3-2, and at the central α point, β point, and γ point. The temperature difference is relatively small. Therefore, when the recording mark 9 is formed, when the temperature exceeds the critical temperature at which the optical characteristics change at the β point and the γ point, the central α point is closest to the central α point without exceeding the vaporization (evaporation) temperature. The surface of the transparent substrate (not shown) does not exceed the heat distortion temperature.

  In contrast, when there is a step in a part of the recording film 3-2 as shown in FIG. 5B, the δ point and the ε point are inclined from the direction in which the recording layer 3-2 is arranged. Since the laser beam 7 is irradiated, the irradiation amount of the laser beam 7 per unit area is relatively decreased as compared with the central α point, and as a result, the recording layer 3-2 at the δ point and the ε point is reduced. Temperature rise is reduced. Since there is heat emission toward the light reflecting layer 4-2 at the δ point and the ε point, the temperature reached at the δ point and the ε point is significantly lower than that at the central α point. For this reason, heat flows from the β point to the δ point and heat flows from the γ point to the ε point, so the temperature difference between the β point and the γ point with respect to the central α point becomes very large. During recording, the amount of temperature rise at the β and γ points is low and does not exceed the critical temperature at which changes in optical characteristics occur at the β and γ points. As a countermeasure, it is necessary to increase the exposure amount (recording power) of the laser beam 7 in order to cause a change in optical characteristics at the β point and the γ point (in order to make the temperature higher than the critical temperature). In the recording film structure shown in FIG. 5B, the temperature difference between the β point and the γ point at the center α point is very large. Therefore, when the temperature rises to the temperature at which the optical characteristics change at the β point and the γ point, the center α The vaporization (evaporation) temperature is exceeded at a point, or the surface of a transparent substrate (not shown) near the center α point is likely to exceed the thermal deformation temperature.

  Further, even when the surface of the recording layer 3-2 on the receiving side of the laser beam 7 is perpendicular to the irradiation direction of the laser beam 7, the thickness of the recording layer 3-2 varies depending on the location. The structure is difficult to cause the optical characteristic change in the recording layer 3-2 of the present embodiment. For example, as shown in FIG. 5C, the thickness Dl of the peripheral portion is significantly thinner than the thickness Dg of the recording layer 3-2 at the center α point (for example, the equations (2) and (4) are If you are not satisfied). Although heat is emitted toward the light reflecting layer 4-2 even at the center α point, since the recording layer 3-2 has a sufficiently thick thickness Dg, it can accumulate heat and reach a high temperature. In contrast, since the heat is released toward the light reflecting layer 4-2 without sufficiently storing heat at the ζ point and η point where the thickness of the recording layer 3-2 is D1 significantly smaller, the temperature rise amount is increased. Few. As a result, not only the release of heat toward the light reflection layer 4-2, but also the release of heat from the β point → δ point → ζ point, or the release of heat from the γ point → ε point → η point, Similar to FIG. 5B, the temperature difference between the β point and the γ point at the center α point becomes very large. If the exposure amount (recording power) of the laser beam 7 is increased to cause a change in optical characteristics at the β point and the γ point (in order to make the temperature higher than the critical temperature), the vaporization (evaporation) temperature may be exceeded at the central α point or the center. The surface of the transparent substrate (not shown) in the vicinity of the part α is likely to exceed the heat distortion temperature.

  Based on the above-described content, the technical contents and the thickness of the recording layer in the present embodiment regarding the pre-groove shape / dimension for performing “setting of environment (recording film structure and shape)” in which the recording principle of the present embodiment is likely to occur The technical contrivance contents in this embodiment regarding the distribution will be described with reference to FIG. 6A shows a recording film structure in a conventional write-once information storage medium such as a CD-R or DVD-R, and FIGS. 6B and 6C show a recording film structure in the present embodiment. In this description, recording marks 9 are formed in the pregroove area 11 as shown in FIG.

3-2-D] Basic Characteristics of Pregroove Shape / Dimension in the Present Embodiment As shown in FIG. 6A, in the conventional write-once information storage medium such as CD-R and DVD-R, the pregroove area 11 has In many cases, it had a “V-groove” shape. In the case of this structure, as described with reference to FIG. 5B, the energy absorption efficiency of the laser light 7 is low, and the temperature distribution unevenness in the recording layer 3-2 is very large. In order to approach the ideal state of FIG. 5A, the feature of the present embodiment is that at least “a planar region perpendicular to the traveling direction of the incident laser beam 7 is provided in the pregroove region 11 on the transparent substrate 2-2 side”. Yes. As described with reference to FIG. 5A, it is desirable to make this plane area as wide as possible. Therefore, not only the planar area is provided in the pregroove area 11, but also the width Wg of the pregroove area is larger than the width Wl of the land area (Wg> Wl). In this description, the width Wg of the pre-groove area and the width Wl of the land area are set to a plane having an intermediate height between the height at the plane position of the pre-groove area and the height at the highest position of the land area. It is defined as each width at the position where the slope of the crossing.

  Data is recorded in a recordable information storage medium that has been studied by thermal analysis and actually manufactured, and substrate deformation is observed by a cross-sectional SEM (scanning electron microscope) image at the position of the recording mark 9, and vaporization (evaporation) in the recording layer 3-2 is performed. As a result of repeating the observation of the presence or absence of cavities generated by (1), it was found that there is an effect by making the width Wg of the pregroove region wider than the width Wl of the land region (Wg> Wl). Furthermore, the ratio of the pre-groove area width Wg to the land area width Wl is made larger than Wg: Wl = 6: 4, preferably Wg: Wl = 7: 3, so that the recording layer 3-2 can be more stably recorded. It is considered that local optical characteristic changes are likely to occur in the inside. When the difference between the pre-groove region width Wg and the land region width Wl is increased in this way, a flat surface disappears on the land region 12 as shown in FIG. In the conventional DVD-R disc, pre-pits (land pre-pits: not shown) are formed in the land area 12, and the address information and the like are recorded in advance here. Therefore, it is indispensable to form a flat region in the land region 12, and as a result, the pregroove region 11 often has a “V-groove” shape. In the conventional CD-R disc, a wobble signal is input to the pre-groove area 11 by frequency modulation. In a conventional frequency modulation method using a CD-R disc, the slot interval (details will be described later in the description of each format) is not constant, and phase alignment (PLL: PhaseLockLoop synchronization) at the time of wobble signal detection is relatively was difficult. For this reason, the wall surface of the pre-groove region 11 is concentrated near the center where the intensity of the reproduction focused spot is the highest (close to the V-groove) and the wobble amplitude is increased to guarantee the wobble signal detection accuracy. As shown in FIGS. 6B and 6C, the flat region in the pre-groove region 11 in the present embodiment is widened, and the slope of the pre-groove region 11 is relatively outward from the center position of the reproduction focused spot. If moved, it becomes difficult to obtain a wobble detection signal. In the present embodiment, the width Wg of the pre-groove area is increased, and the H format or FSK (Frequency Shift Keying) using phase modulation (PSK: Phase Shift Keying) in which the slot interval at the time of wobble detection is always kept fixed. By combining the B format using STW (Saw Tooth Wobble), it is possible to guarantee stable recording characteristics with low recording power (suitable for high-speed recording and multi-layering) as well as stable wobble signal detection characteristics. There is a big feature. In particular, in the H format, in addition to the above combinations, “lower the wobble modulation area ratio than the non-modulation area” makes it easier to synchronize when detecting wobble signals, and further stabilizes the wobble signal detection characteristics. I am letting.

3-2-E] Basic Characteristics of Recording Layer Thickness Distribution in the Present Embodiment In this description, the thickest recording layer 3-2 in the land area 12 is shown in FIGS. Is defined as the recording layer thickness Dl in the land area, and the thickness at the thickest recording layer 3-2 in the pregroove area 11 is defined as the recording layer thickness Dg in the pregroove area. As already described with reference to FIG. 5C, by relatively increasing the recording layer thickness Dl in the land area, local optical characteristic changes are easily caused in the recording layer 3-2 at the time of recording. Become.

  In the same manner as described above, thermal analysis is performed and data is recorded on a recordable information storage medium that is actually manufactured, and the deformation of the substrate is observed by a cross-sectional SEM (scanning electron microscope) image at the position of the recording mark 9 and in the recording layer 3-2. As a result of repeated observation of the presence or absence of cavities caused by vaporization (evaporation), the ratio of the recording layer thickness Dg in the pre-groove area to the recording layer thickness Dl in the land area is at most Dg: Dl = 4: 1 or less. There is a need to do. Furthermore, when Dg: Dl = 3: 1 or less, preferably Dg: Dl = 2: 1 or less, the stability of the recording principle in this embodiment can be guaranteed.

3-3) Recording characteristics common to the organic dye recording film in the present embodiment As described in [γ] as one of “3-2-B] Basic features common to the organic dye recording material in the present embodiment” Recording power control is a major feature of this embodiment.

  The formation of the recording mark 9 due to a local change in optical characteristics in the recording layer 3-2 is based on the conventional plastic deformation temperature of the transparent substrate 2-2, the thermal decomposition temperature in the recording layer 3-2, and the vaporization (evaporation) temperature. However, since it occurs at a much lower temperature, the transparent substrate 2-2 does not locally exceed the plastic deformation temperature during recording or does not exceed the thermal decomposition temperature or vaporization (evaporation) temperature locally in the recording layer 3-2. Limit the upper limit of recording power.

In parallel with the examination by thermal analysis, the apparatus described later in “4-1) Description of structure and characteristics of reproducing apparatus or recording / reproducing apparatus in this embodiment” is used, and “4-3) Recording conditions in this embodiment are determined. The value of the optimum power when recording was performed according to the recording principle shown in the present embodiment using the recording conditions described later in “Description” was also demonstrated. The objective lens NA (Numerical Apperture) value in the recording / reproducing apparatus used in the demonstration experiment was 0.65, and the linear velocity during recording was 6.61 m / s. The value of recording power (Peak Power) defined later in “4-3) Description of recording conditions in this embodiment” is vaporized (evaporated) in most organic dye recording materials at 30 mW, and cavities are formed in the recording marks. The temperature of the transparent substrate 2-2 near the recording layer 3-2 greatly exceeds the glass transition temperature. The temperature of the transparent substrate 2-2 near the recording layer 3-2 at 20 mW is the plastic deformation temperature. (Glass transition temperature) reached ◎ It was found that 15 mW or less is desirable in anticipation of margins such as surface blurring and warping of the information storage medium and recording power fluctuation.

The “recording power” described above means the sum of the exposure amount irradiated to the recording layer 3-2. The light energy density in the central portion of the focused spot and the highest light intensity density is a parameter to be studied in this embodiment. Since the focused spot size is inversely proportional to the NA value, the light energy density at the center of the focused spot increases in proportion to the square of the NA value. Therefore, [Recording power adaptable to different NA]
= [Recording power at NA = 0.65] × 0.652 / NA2 (5)
Can be converted into an optimum recording power value in the B format described later or another format (different NA value) shown in FIG. 1 (D3).

Furthermore, the optimum recording power varies depending on the linear velocity V during recording. In general, it is said that the optimum recording power changes in proportion to the 1/2 power of the linear velocity V in the phase change recording material, and changes in proportion to the linear velocity V in the organic dye recording material. Therefore, the optimum recording power conversion formula taking into account the linear velocity V is an extension of formula (5) [General recording power]
= [NA = 0.65; Recording power at 6.6 m / s]
× (0.65 / NA) 2 × (V / 6.6) (6)
Or [General recording power]
= [NA = 0.65; Recording power at 6.6 m / s]
× (0.65 / NA) 2 × (V / 6.6) 1/2 (7)
It is obtained by. Summarizing the above examination results, as the recording power for guaranteeing the recording principle shown in the present embodiment, [Optimum recording power]
<30 × (0.65 / NA) 2 × (V / 6.6) (8)
[Optimal recording power]
<30 × (0.65 / NA) 2 × (V / 6.6) 1/2 (9)
[Optimal recording power]
<20 × (0.65 / NA) 2 × (V / 6.6) (10)
[Optimal recording power]
<20 × (0.65 / NA) 2 × (V / 6.6) 1/2 (11)
[Optimal recording power]
<15 × (0.65 / NA) 2 × (V / 6.6) (12)
[Optimal recording power]
<15 × (0.65 / NA) 2 × (V / 6.6) 1/2 (13)
It is desirable to set an upper limit value. Among the above formulas, the condition of formula (8) or formula (9) is an indispensable condition, formula (10) or formula (11) is a target condition, and formula (12) or formula (13) is a desirable condition.

3-4) Description of Features Regarding “H → L” Recording Film in the Present Embodiment A recording film having a characteristic that the light reflection amount in the recording mark 9 is lower than the light reflection amount in the unrecorded area is referred to as “H → L”. The recording film called “recording film” and conversely, the recording film that rises is called “L → H” recording film. Among these, “H → L” recording film (1) An upper limit is set for the ratio of the absorbance at the reproduction wavelength to the absorbance at the λmax write position of the light absorption spectrum. (2) The recording mark is changed by changing the light absorption spectrum profile. There is a major feature of this embodiment in the formation of.

  A detailed description of the above contents will be given using FIGS. In the H → L recording film in this embodiment, as shown in FIG. 7, the wavelength of λmax write is shorter than the use wavelength (near 405 nm) used for recording / reproduction. As can be seen from FIG. 8, there is little change in absorbance between unrecorded and recorded in the vicinity of the wavelength of λmax write. If there is little change in absorbance between unrecorded and recorded, the reproduction signal amplitude cannot be increased. In view of the fact that recording or reproduction can be performed stably even if the wavelength of the recording or reproduction laser light source is changed, in this embodiment, as shown in FIG. That is, the recording film 3-2 is designed so as to be on the shorter wavelength side than 355 nm.

  "Chapter 0 Use" when the absorbance at the λmax write position defined as "2-1) Difference in recording principle / difference in recording film structure and fundamental difference in reproduction signal generation" has been normalized to "1" The relative absorbance at 355 nm, 455 nm, and 405 nm described in “Relationship Between Wavelength and This Embodiment” is defined as Ah355, Ah455, and Ah405.

  In the case of Ah405 = 0.0, the light reflectance from the recording film in the unrecorded state matches the light reflectance at 405 nm in the light reflecting layer 4-2. The light reflectance of the light reflecting layer 4-2 will be described later in detail in “6-1) Light reflecting layer”, but here the light reflectance of the light reflecting layer 4-2 is changed for the sake of simplicity of explanation. The explanation will be made assuming 100%.

In the write-once information storage medium using the “H → L” recording film in the present embodiment, the reproduction circuit is made common to the case of using a read-only information storage medium (HD DVD-ROM disc) in the case of a single-layer film on one side. ing. Therefore, the light reflectivity in this case is set to 40 to 85% in accordance with the light reflectivity of the read-only information storage medium (HD DVD-ROM disc) having a single-sided single layer film. For this purpose, it is necessary to set the light reflectance at an unrecorded position to 40% or more. Since 1-0.4 = 0.6, the absorbance Ah405 at 405 nm is Ah405 ≦ 0.6 (14)
I can intuitively understand what should be done. When the above formula (14) is satisfied, it can be easily understood that the light reflectance at the unrecorded position can be 40% or more. Recording materials are selected. The above equation (14) assumes that the light reflectivity is 0% when the light reflection layer 4-2 is reflected through the recording layer 3-2 with the light having the wavelength of λmax write in FIG. However, in actuality, the light reflectivity at this time does not become 0% but has a certain degree of light reflectivity, and strictly, correction to the equation (14) is necessary. In FIG. 7, when the light reflectance when the light reflection layer 4-2 is reflected through the recording layer 3-2 with the light having the wavelength of λmax write is defined as Rλmax write, the light reflectance at the unrecorded position is 40% or more. The strict conditional expression set to 1−Ah405 × (1−Rλmax write) ≧ 0.4 (15)
It becomes. In the case of “H → L” recording film, Rλmax write ≧ 0.25 in many cases, so equation (15) becomes Ah405 ≦ 0.8 (16)
It becomes. In the “H → L” recording film of the present embodiment, it is essential to satisfy the expression (16). Detailed optical film design was performed on condition that the characteristics of the above expression (14) were given and the condition of the expression (3) or (4) was satisfied as the film thickness of the recording layer 3-2. As a result, when taking into account various margins such as film thickness fluctuation and reproduction light wavelength fluctuation, Ah405 ≦ 0.3 (17)
Is desirable. Assuming equation (14),
Ah455 ≦ 0.6 (18)
Or Ah355 ≦ 0.6 (19)
When set to, the recording / reproducing characteristics are further stabilized. This is because when the formula (14) is satisfied and at least one of the formulas (18) and (19) is satisfied, the range is 355 nm to 405 nm, or the range 405 nm to 455 nm (sometimes 355 nm to 455 nm). This is because the value of Ah becomes 0.6 or less (within this range), so that even if the emission wavelength of the recording laser light source (or reproducing laser light source) varies, the absorbance value does not change greatly.

  The specific recording principle of the “H → L” recording film in this embodiment is “α” in “3-2-B] Basic features common to organic dye recording materials in this embodiment” already described. Among the recording mechanisms listed, the phenomenon of “change in arrangement between molecules” or “change in molecular structure within the molecule” is used. As a result, the light absorption spectrum profile is changed as described in (2) above. The light absorption spectrum profile in the recording mark in the present embodiment is indicated by a solid line in FIG. 8, and the light absorption spectrum profile at an unrecorded place is overlapped by a broken line so that both can be compared. In the present embodiment, the light absorption spectrum profile in the recording mark changes relatively broadly, causing a change in the molecular structure inside the molecule, possibly causing the precipitation of carbon atoms (coal tarization). By reproducing the wavelength λlmax at which the absorbance within the recording mark is maximized closer to the reproduction wavelength 405 nm than the value of the wavelength λmax write at the unrecorded position, a reproduction signal is generated on the “H → L” recording film. There is a feature of this embodiment. As a result, the absorbance at the wavelength λlmax where the absorbance is highest is smaller than “1”, and the value of the absorbance Al405 at the reproduction wavelength of 405 nm is larger than the value of Ah405. As a result, the total light reflectance in the recording mark is lowered.

In the H format in the present embodiment, ETM (Eight to Twelve: 8-bit data code is converted into 12 channel bits), RLL (1, 10) (corresponding to the channel bit length T in the modulated code string) The minimum inversion length is 2T and the maximum inversion length is 11T). The performance of the reproduction circuit described later in “4-2) Description of the reproduction circuit in this embodiment” was evaluated. In order to reproduce stably with the reproduction circuit [unrecorded with a sufficiently long length (11T)] The ratio of [the difference value I11≡I11H−I11L between the reproduction signal amount I11L from the recording mark having a sufficiently long length (11T)] to the reproduction signal amount I11H from the area] is at least I11 / I11H ≧ 0.4 (20)
Desirably I11 / I11H> 0.2 (21)
It was found that it was necessary to satisfy. In the present embodiment, the PRML method is used at the time of reproducing a signal recorded at high density, and a signal processing circuit and a state transition diagram shown in FIGS. 13 to 15 (detailed description will be described later) are used. In order to detect accurately with the PRML method, the linearity of the reproduction signal is required. As a result of analyzing the signal processing circuit characteristics shown in FIGS. 13 and 14 based on the state transition diagram shown in FIG. 15, in order to ensure the linearity of the reproduction signal, a recording having a length of 3T is required. When the reproduction signal amplitude from the repetitive signal of the mark and unrecorded space is I3, the ratio of this value to I11 is I3 / I11 ≧ 0.35 (22)
Preferably I3 / I11> 0.2 (23)
It was also found that there is a need to satisfy. The technical feature of this embodiment is that the value of Al405 is set so as to satisfy the expressions (20) and (21) while considering the condition of the above expression (16). Refer to the equation (16) 1-0.3 = 0.7 (24)
It becomes. Taking the equation (24) into view, from the correspondence with the equation (20), (Al405-0.3) /0.7≧0.4
Al405 ≧ 0.58 (25)
The conditions are derived. The formula (25) is a formula derived from a very rough examination result and merely shows a basic idea. Since the setting range of Ah405 is defined by the equation (16), in this embodiment, at least Al405> 0.3 (26) as the condition of Al405.
Is essential.

  As a method for selecting an organic dye material suitable for a specific “H → L” recording film, in this embodiment, the refractive index range in an unrecorded state is n32 = 1.3 to 2.0 based on the optical film design. An organic dye material having an absorption coefficient range of k32 = 0.1 to 0.2, preferably n32 = 1.7 to 1.9 and an absorption coefficient range of k32 = 0.15 to 0.17 is selected and described above. Satisfies a series of conditions.

  In the “H → L” recording film shown in FIG. 7 or FIG. 8, the wavelength of λmax write is shorter than the wavelength of reproduction light or recording / reproduction light (for example, 405 nm) in the light absorption spectrum in the unrecorded area. However, the present invention is not limited thereto, and for example, the wavelength of λmax write may be longer than the wavelength of reproduction light or recording / reproduction light (for example, 405 nm).

In order to satisfy the formula (22) or the formula (23), the thickness Dg of the recording layer 3-2 greatly affects. For example, when the thickness Dg of the recording layer 3-2 greatly exceeds the allowable value, only a part of the optical characteristics in contact with the transparent substrate 2-2 in the recording layer 3-2 changes as the state after the recording mark 9 is formed. As a result, the optical characteristics of the portion in contact with the light reflecting layer 4-2 adjacent to the location remain the same as those of other unrecorded areas. As a result, the change in the amount of reproduced light is reduced, the value of I3 in the expression (22) or (23) is decreased, and the condition of the expression (22) or (23) cannot be satisfied. Therefore, in order to satisfy the expression (22), it is necessary to change the optical characteristics of the portion in contact with the light reflection layer 4-2 in the recording mark 9 as shown in FIGS. 6B and 6C. Further, if the thickness Dg of the recording layer 3-2 greatly exceeds the allowable value, a temperature gradient is generated in the thickness direction in the recording layer 3-2 at the time of recording mark formation, and the light reflecting layer 4- in the recording layer 3-2. Before reaching the optical property change temperature at the portion in contact with 2, the vaporization (evaporation) temperature of the portion in contact with the transparent substrate 2-2 is exceeded, or the thermal deformation temperature is exceeded in the transparent substrate 2-2. For this reason, in the present embodiment, the thickness Dg of the recording layer 3-2 is set to “3T” or less in order to satisfy the equation (22) by thermal analysis, and the condition of the recording layer 3-2 is satisfied as a condition for satisfying the equation (23). The thickness Dg is set to “3 × 3T” or less. Basically, when the thickness Dg of the recording layer 3-2 is "3T" or less, the equation (22) can be satisfied. However, the influence of tilt and defocusing caused by surface wobbling / warping of the write-once information storage medium can be satisfied. Considering the margin for, there may be a case where the value is equal to or less than “T”. In consideration of the results of the expressions (1) and (2) already described, the range of the thickness Dg of the recording layer 3-2 in this embodiment is 9T ≧ Dg ≧ λ / 8n32 (27)
Desirable conditions are 3T ≧ Dg ≧ λ / 4n32 (28)
The thickness Dg of the recording layer 3-2 is set within the range given by. However, the most severe condition is T ≧ Dg ≧ λ / 4n32 (29)
It is also possible to. As will be described later, the channel bit length T is 102 nm for the H format and 69 nm to 80 nm for the B format. Therefore, the 3T value is 306 nm for the H format, 207 nm to 240 nm for the B format, and the 9T value is the H format. Is 918 nm and B format is 621 nm to 720 nm. Here, the “H → L” recording film has been described, but the conditions of the equations (27) to (29) are not limited thereto, and can be applied to the “L → H” recording film.

Chapter 4 Description of Reproducing Device or Recording / Reproducing Device and Recording Conditions / Reproducing Circuit 4-1) Structure and Characteristic Description of Reproducing Device or Recording / Reproducing Device in the Present Embodiment FIG. 9 shows. In FIG. 9, the upper side of the control unit 143 mainly represents an information recording control system for an information storage medium. In the embodiment of the information reproducing apparatus, a structure excluding the information recording control system in FIG. In FIG. 9, a thick solid line arrow indicates a flow of main information indicating a reproduction signal or a recording signal, a thin solid line arrow indicates a flow of information, a one-dot chain line arrow indicates a reference clock line, and a thin broken line arrow indicates a command indication direction. .

  Although not shown in the information recording / reproducing unit 141 shown in FIG. 9, an optical head is arranged. In this embodiment, the wavelength of the light source (semiconductor laser) used in the optical head is 405 nm. However, the present invention is not limited to this, and as described above in the present embodiment, the wavelength used is 620 nm or less or 530 nm or less, or the range of 355 to 455 nm. It is possible to use any light source. In addition, two objective lenses used for condensing the light of the above wavelength on the information storage medium in the optical head are mounted, and the NA value is 0 when recording / reproducing with respect to the H format information storage medium. When an objective lens of .65 is used and recording / reproducing is performed on an information storage medium of B format, the objective lens is switched to use an objective lens of NA = 0.85. As the intensity distribution of the incident light immediately before entering the objective lens, the relative intensity around the objective lens (opening boundary position) when the center intensity is “1” is referred to as “RIM Intensity”. The value of the RIM intensity in the H format is set to 55 to 70%. The amount of wavefront aberration in the optical head at this time is optically designed to be a maximum of 0.33λ (0.33λ or less) with respect to the operating wavelength λ.

  In this embodiment, PRML (Partial Response Maximum Likelihood) is used for information reproduction to increase the density of the information storage medium (FIG. 1 [A]). As a result of various experiments, if PR (1, 2, 2, 2, 1) is used as the PR class to be used, the linear density can be increased and the reliability of the reproduction signal (for example, servo correction error such as defocusing and track deviation) In this embodiment, PR (1, 2, 2, 2, 1) is employed (FIG. 1 (A1)). In the present embodiment, the modulated channel bit string is recorded on the information storage medium in accordance with the (d, k; m, n) modulation rule (in the above described method, it means RLL (d, k) of m / n modulation). is doing. Specifically, ETM (Eight to Twelve Modulation) that converts 8-bit data into 12 channel bits (m = 8, n = 12) is adopted as the modulation method, and “0” is set in the modulated channel bit string. As a run-length limited RLL constraint that limits the length that follows, the RLL (1, 10) condition is set such that the minimum value where “0” continues is d = 1 and the maximum value is k = 10. In this embodiment, the channel bit interval is shortened to near the limit in order to increase the density of the information storage medium. As a result, for example, when a pattern “10101010101010101010101010”, which is a repetition of the pattern of d = 1, is recorded on the information storage medium and the data is reproduced by the information recording / reproducing unit 141, the cutoff frequency of the MTF characteristic of the reproducing optical system Therefore, the signal amplitude of the reproduced raw signal is almost buried in noise. Therefore, the PRML (Partial Response Maximum Likelihood) technique is used as a method of reproducing the recording marks or pits whose density is close to the limit (cutoff frequency) of the MTF characteristics. That is, the signal reproduced from the information recording / reproducing unit 141 is subjected to reproduction waveform correction by the PR equalization circuit 130. The AD converter 169 samples the signal after passing through the PR equalization circuit 130 in accordance with the timing of the reference clock 198 sent from the reference clock generation circuit 160 and converts it into a digital quantity, and the Viterbi decoder 156 performs Viterbi decoding. Get processed. The data after the Viterbi decoding process is processed as the same data as the binarized data at the conventional slice level. When the PRML technique is employed, the error rate of data after Viterbi decoding increases when the sampling timing in the AD converter 169 is shifted. Therefore, in order to increase the accuracy of the sampling timing, the information reproducing apparatus or information recording / reproducing apparatus of this embodiment has a sampling timing extraction circuit (a combination of the Schmitt trigger binary circuit 155 and the PLL circuit 174). This Schmitt trigger circuit has a characteristic that the slice reference level for binarization has a specific width (actually the forward voltage value of the diode) and is binarized only when the specific width is exceeded. Yes. Therefore, for example, as described above, when the pattern “10101010101010101010101010” is input, since the signal amplitude is very small, binarization switching does not occur, and the pattern is sparser than that. For example, “1001001001001001001001” And the like, the amplitude of the reproduced raw signal is increased, so that the polarity of the binarized signal is switched by the Schmitt trigger binarization circuit 155 at the timing of “1”. In this embodiment, the NRZI (Non Return to Zero Invert) method is employed, and the position of “1” in the pattern coincides with the edge portion (boundary portion) of the recording mark or pit.

  The PLL circuit 174 detects a frequency and phase shift between the binarized signal output from the Schmitt trigger binarizing circuit 155 and the reference clock 198 signal sent from the reference clock generating circuit 160 to detect the PLL circuit 174. The frequency and phase of the output clock are changed. In the reference clock generation circuit 160, the output signal of the PLL circuit 174 and the decoding characteristic information of the Viterbi decoder 156 (specifically, although not shown, the convergence length in the path metric memory in the Viterbi decoder 156 (until the convergence) Using the information of distance), feedback is applied to the reference clock 198 (frequency and phase) so that the error rate after Viterbi decoding is lowered. The reference clock 198 generated by the reference clock generation circuit 160 is used as a reference timing at the time of reproduction signal processing.

  The synchronization code position extraction unit 145 detects the position of the synchronization code (sync code) mixed in the output data string of the Viterbi decoder 156, and plays a role of extracting the start position of the output data. The demodulation circuit 152 demodulates the data temporarily stored in the shift register circuit 170 with the start position as a reference. In the present embodiment, the conversion table recorded in the demodulation conversion table recording unit 154 is referred to every 12 channel bits to restore the original bit string. Thereafter, error correction processing is performed by the ECC decoding circuit 162 and descrambled by the descramble circuit 159. In the recording type (rewritable type or write-once type) information storage medium of this embodiment, address information is recorded in advance by wobble modulation. The wobble signal detection unit 135 reproduces this address information (that is, determines the contents of the wobble signal) and supplies the control unit 143 with information necessary for accessing the desired location.

  An information recording control system located above the control unit 143 will be described. Data ID information is generated from the data ID generation unit 165 according to the recording position on the information storage medium, and when the copy control information is generated by the CPR_MAI data generation unit 167, the data ID, IED, CPR_MAI, EDC addition unit 168 records it. Various information such as data ID, IED, CPR_MAI, and EDC is added to the information to be processed. Thereafter, after descrambling by the descrambling circuit 157, an ECC block is constituted by the ECC encoding circuit 161, converted into a channel bit string by the modulation circuit 151, and then a synchronization code is added by the synchronization code generating / adding unit 146. Data is recorded on the information storage medium in the information recording / reproducing unit 141. At the time of modulation, a DSV (Digital Sum Value) value calculation unit 148 sequentially calculates a modulated DSV value and feeds it back to code conversion at the time of modulation.

  FIG. 10 shows a detailed structure of the peripheral portion including the synchronization code position detection unit 145 shown in FIG. The synchronization code is composed of a synchronization position detection code portion having a fixed pattern and a variable code portion. From the channel bit string output from the Viterbi decoder 156, the position of the synchronization position detection code section having the fixed pattern is detected by the synchronization position detection code detection section 182 and the data of the variable code existing before and after that is detected. The variable code transfer units 183 and 184 determine which sync frame in the sector, which will be described later, the sync code extracted and detected by the sync frame position identification code content identification unit 185 is determined. User information recorded on the information storage medium is sequentially transferred to the shift register circuit 170, the demodulation processing unit 188 in the demodulation circuit 152, and the ECC decoding circuit 162 in this order.

In the present embodiment, in the H format, the data area, the data lead-in area, and the data lead-out area use the PRML method for reproduction, thereby achieving high density of the information storage medium (particularly improving the linear density) In the system lead-in area and system lead-out area, the slice level detection method is used for reproduction, so that compatibility with the current DVD is ensured and reproduction is stabilized. (Details will be described later in “Chapter 7 Explanation of H Format”.)
4-2) Description of Reproduction Circuit in the Present Embodiment FIG. 11 shows an embodiment of a signal reproduction circuit using a slice level detection method used at the time of reproduction in the system lead-in area and system lead-out area. 11 is fixed in the optical head existing in the information recording / reproducing unit 141 in FIG. A signal obtained by summing the detection signals obtained from the respective light detection cells 1a, 1b, 1c, and 1d of the quadrant photodetector 302 is referred to as “read channel 1 signal” herein. The pre-amplifier 304 to the slicer 310 in FIG. 11 correspond to the detailed structure in the slice level detection circuit 132 in FIG. After passing through 306, waveform equalization processing is performed by the pre-equalizer 308. According to experiments, it has been found that the pre-equalizer 308 has the smallest circuit scale and can accurately detect a reproduction signal when a 7-tap equalizer is used. Therefore, this embodiment also uses a 7-tap equalizer. . 11 corresponds to the PLL circuit in FIG. 9, and the demodulation circuit and ECC decoding circuit 314 in FIG. 11 correspond to the demodulation circuit 152 and the ECC decoding circuit 162 in FIG.

  The detailed structure in the slicer 310 circuit of FIG. 11 is shown in FIG. The binarized signal after slicing is generated using a comparator 316. In this embodiment, the duty feedback method is used, and the low-pass filter output signal is set to the binarization slice level with respect to the binary signal inverted signal after binarization. In this embodiment, the cut-off frequency of the low-pass filter is set to 5 KHz. If the cut-off frequency is high, the slice level fluctuation is fast, so that it is easily affected by noise. Conversely, if the cut-off frequency is low, the response at the slice level is slow, so that it is easily affected by dust and scratches on the information storage medium. The relationship between RLL (1, 10) and the reference frequency of the channel bit is set to 5 KHz in consideration of the relationship between RLL (1, 10) and the channel bit reference frequency.

  FIG. 13 shows a signal processing circuit using the PRML detection method used for signal reproduction in the data area, data lead-in area, and data lead-out area. 13 is fixed in the optical head existing in the information recording / reproducing unit 141 in FIG. A signal obtained by summing the detection signals obtained from the respective light detection cells 1a, 1b, 1c, and 1d of the quadrant photodetector 302 is referred to as “read channel 1 signal” herein. The detailed structure in the PR equalization circuit 130 in FIG. 9 is composed of circuits from the preamplifier circuit 304 to the tap controller 332, the equalizer 330, and the offset canceller 336 in FIG. A PLL circuit 334 in FIG. 13 is a part of the PR equalization circuit 130 in FIG. 9 and is different from the Schmitt trigger binarization circuit 155 in FIG. The primary cutoff frequency of the high-pass filter circuit 306 in FIG. 13 is set to 1 KHz. The pre-equalizer circuit 308 uses a 7-tap equalizer as in FIG. 11 (because the use of 7-tap has the smallest circuit scale and can accurately detect a reproduction signal). The A / D converter circuit 324 has a sample clock frequency of 72 MHz and a digital output of 8 bits. In the PRML detection method, if it is affected by the level fluctuation (DC offset) of the entire reproduction signal, an error is likely to occur during Viterbi demodulation. In order to eliminate the influence, the offset canceller 336 corrects the offset using a signal obtained from the equalizer output. In the embodiment shown in FIG. 13, adaptive equalization processing is performed in the PR equalization circuit 130. Therefore, a tap controller for automatically correcting each tap coefficient in the equalizer 330 using the output signal of the Viterbi decoder 156 is used.

  The structure in the Viterbi decoder 156 shown in FIG. 9 or FIG. 13 is shown in FIG. The branch metric calculation unit 340 calculates branch metrics for all branches that can be predicted for the input signal, and sends the values to the ACS 342. ACS 342 is an abbreviation for Add Compare Select, calculates a path metric obtained by adding a branch metric corresponding to each path that can be predicted in ACS 342, and transfers the calculation result to the path metric memory 350. At this time, the ACS 342 performs calculation processing with reference to information in the path metric memory 350. In the path memory 346, each path (transition) situation that can be predicted and the path metric value calculated by the ACS 342 corresponding to each path are temporarily stored. The output switching unit 348 compares the path metrics corresponding to the paths, and selects the path having the minimum path metric value.

  FIG. 15 shows state transitions in the PR (1, 2, 2, 2, 1) class in the present embodiment. Since only the transitions shown in FIG. 15 are possible for the state (state) that can be taken in the PR (1, 2, 2, 2, 1) class, the Viterbi decoder 156 uses the transition diagram shown in FIG. Finding paths that can exist (and can be expected).

4-3) Explanation of recording conditions in this embodiment “3-3) Recording characteristics common to the organic dye recording film in this embodiment” explained the optimum recording power (peak power) in this embodiment. However, the recording waveform (exposure conditions at the time of recording) used when examining the optimum recording power will be described with reference to FIG.

  There are four exposure levels, recording power (peak power), bias power 1 (Bias power 1), bias power 2 (Bias power 2), and bias power 3 (Bias power 3). When a long recording mark 9 (4T or more) is formed, modulation is performed in the form of a multipulse between recording power (peak power) and bias power 3 (Bias power 3). In this embodiment, the minimum mark length with respect to the channel bit length T is 2T in both “H format” and “B format” methods. When recording the minimum mark of 2T, as shown in FIG. 16, one write pulse at the recording power (peak power) level is used after the bias power 1 (Bias power 1), and the write pulse is used. Immediately after, the bias power becomes 2 (Bias power 2). When recording a recording mark 9 having a length of 3T, two write pulses of the first pulse and the last pulse of the recording power (peak power) level that come after the bias power 1 (Bias power 1) were exposed. After that, it becomes bias power 2 (Bias power 2). In the case of recording a recording mark 9 having a length of 4T or more, the bias power 2 (Bias power 2) is obtained after exposure with a multi-pulse and a last pulse.

  A vertical broken line in FIG. 16 indicates a channel clock period. When recording a 2T minimum mark, it rises from a position delayed by TSFP from the clock edge, and falls from the edge one clock later at a position behind TELP. The period immediately after that becomes bias power 2 is defined as TLC. The values of TSFP, TELP, and TLC are recorded in the physical format information PFI in the control data zone CDZ as described later in the case of the H format. When a long recording mark of 3T or more is formed, the signal rises from a position delayed by TSFP from the clock edge, and ends with the last pulse. Immediately after the last pulse, the bias power is 2 (Bias power 2) during the TLC period, and the deviation time from the clock edge of the rising / falling timing of the last pulse is defined by TSLP and TELP. Further, the time measured from the clock edge at the falling timing of the leading pulse is defined by TEFP, and the interval of one multipulse is defined by TMP.

Each interval of TELP-TSFP, TMP, TELP-TSLP, and TLC is defined by a half width with respect to the maximum value as shown in FIG. In the present embodiment, the parameter setting range is 0.25T ≦ TSFP ≦ 1.50T (30)
0.00T ≦ TELP ≦ 1.00T (31)
1.00T ≦ TEFP ≦ 1.75T (32)
−0.10T ≦ TSLP ≦ 1.00T (33)
0.00T ≦ TLC ≦ 1.00T (34)
0.15T ≦ TMP ≦ 0.75T (35)
And Furthermore, in this embodiment, the values of the above parameters can be changed as shown in Table 2 according to the length of the recording mark (Mark length) and the space length (Leading / Trailing space length) immediately before / after that. .

  The optimum recording power of the write-once information storage medium recorded according to the recording principle shown in the present embodiment, which has already been described in “3-3) Recording characteristics common to the organic dye recording film in the present embodiment”, was investigated. Table 3 shows the values of each parameter.

  The values of bias power 1 (Bias power 1), bias power 2 (Bias power 2), and bias power 3 (Bias power 3) at this time are 2.6 mW, 1.7 mW, and 1.7 mW, and the reproduction power is 0. It was 4mW.

Chapter 5 Specific Description of Organic Dye Recording Film in this Embodiment 5-1) Characteristic Description Regarding “L → H” Recording Film in this Embodiment Characteristic that light reflection amount is reduced in a recording mark as compared with an unrecorded area The “L → H” recording film having the following will be described. The recording principle when this recording film is used is mainly the recording principle described in “3-2-B] Basic features common to the organic dye recording material in this embodiment”. Changes in the electronic structure (electron orbital) for electrons contributing to the phenomenon (decolorization, etc.)
• Change the characteristics of the absorption spectrum using any of the intermolecular alignment changes. Regarding the “L → H” recording film, there is a great feature in that the reflection amount range at the unrecorded location and the recorded location is specified taking into consideration the characteristics of a read-only information storage medium having a single-sided two-layer structure. Yes. FIG. 18 shows the light reflectance range in the unrecorded area (non-recording portion) of the “H → L” recording film and the “L → H” recording film defined in this embodiment. In this embodiment, it is defined that the reflectance lower limit value δ in the non-recording portion of the “H → L” recording film is higher than the upper limit value γ in the non-recording portion of the “L → H” recording film. When the information recording / reproducing apparatus or the information reproducing medium is mounted on the information recording / reproducing apparatus, the light reflectance of the non-recording part is measured by the slice level detecting unit 132 or the PR equalizing circuit 130 shown in FIG. Since the “recording film” or the “L → H” recording film can be discriminated, it is very easy to discriminate the type of the recording film. As a result of measuring the “H → L” recording film and the “L → H” recording film prepared by changing many manufacturing conditions, the lower limit reflectance δ at the non-recording portion of the “H → L” recording film When the light reflectance α between the upper limit value γ and the upper limit value γ in the non-recording portion of the “L → H” recording film is within the range of 32% to 40%, the productivity of the recording film is high and the cost of the medium is reduced. I found it easy. The light reflectance range 801 of the “L → H” recording film non-recording portion (“L” portion) is matched with the light reflectance range 803 of the single-sided two-recording layer in the read-only information storage medium, and “H → L” recording is performed. If the light reflectance range 802 of the non-recording portion (“H” portion) of the film is matched with the single-layer single-layer light reflectance range 804 in the read-only information storage medium, compatibility with the read-only information storage medium is achieved. Since the reproduction circuit of the information reproducing apparatus can be commonly used, the information reproducing apparatus can be made at low cost. As a result of creating and measuring “H → L” recording films and “L → H” recording films prepared by changing many manufacturing conditions, in order to increase the productivity of the recording films and facilitate the cost reduction of the medium In the present embodiment, the lower limit value β of the light reflectance of the non-recording portion (“L” portion) of the “L → H” recording film is 18% and the upper limit value γ is 32%. The light reflectance lower limit value δ of the non-recording portion (“H” portion) was set to 40%, and the upper limit value ε was set to 85%.

  FIG. 19 and Table 4 show the reflectances at the non-recording position and the already-recorded position in various recording films in the present embodiment.

  When the H format (refer to “Chapter 7 Description of H Format”) is adopted, the light reflectance range in the non-recording portion is defined as shown in FIG. “In the recording film, signals appear in the same direction in the embossed area (system lead-in area SYLDI and the like) and the recording mark area (data lead-in area DTLDI, data lead-out area DTLDO, and data area DTA). Similarly, in the “H → L” recording film, the embossed area (system lead-in area SYLDI, etc.) and the recording mark area (data lead-in area DTLDI, data lead-out area DTLDO, data area DTA) are reversed in the reverse direction with the groove level as a reference. A signal appears. Using this phenomenon, not only can it be used for recording film identification between “L → H” recording film and “H → L” recording film, but also supports “L → H” recording film and “H → L” recording film. It is easy to design the detection circuit. In addition, the reproduction signal characteristics obtained from the recording marks recorded on the “L → H” recording film shown in the present embodiment are matched with the signal characteristics obtained from the “H → L” recording film, the expressions (20) to (23) ) Is satisfied. As a result, the same signal processing circuit can be used when using either the “L → H” recording film or the “H → L” recording film, and the signal processing circuit can be simplified and reduced in price.

  FIG. 70 to FIG. 72 show another embodiment for the embodiment showing the relationship between the light reflectivity of the “H → L” recording film and the “L → H” recording film shown in FIGS. explain.

  In the present embodiment, as shown in FIG. 6, the width Wg of the pregroove region 11 is set to be wider than the width Wl of the land region 12. As a result, as shown in FIG. 70, the signal level (Iot) groove from the pregroove area 11 when tracking on the pregroove area 11 (in the data lead-in area DTLDI or data area DTA, data lead-out area DTLDO) is increased. It has become a feature.

  The detection signal (and its signal detection circuit) in this embodiment will be described with reference to FIG. Laser light 1117 emitted from the semiconductor laser 1121 passes through a collimator lens 1122 and becomes parallel light. Then, after passing through the beam splitter 1123, the light is condensed on the pre-groove area 1111 of the information recording medium 1101 by the objective lens 1128. The light reflected by the pre-groove region 1111 of the information recording medium 1101 passes through the objective lens 1128 again, is reflected by the beam splitter 1123, passes through the condenser lens 1124, and is irradiated on the photodetector 1125. The light detector 1125 includes a light detection cell 1125-1 and a light detection cell 1125-2, and the signal I1 is detected from the light detection cell 1125-1, and the signal I2 from the light detection cell 1125-2. Are detected.

  FIG. 74 illustrates the structure of another example of the optical head existing in the information recording / reproducing unit 141 of FIG. As shown in FIG. 74, the laser light emitted from the semiconductor laser 1021 becomes parallel light by the collimator lens 1022, is condensed by the objective lens 1028 through the beam splitter 1023, and is within the pre-groove region 1011 of the information recording medium 1001. Is irradiated. The pre-groove region 1011 performs a minute meander (wobble). The light reflected from the wobbled pre-groove region 1011 passes through the objective lens 1028 again, is reflected by the beam splitter 1023, and is irradiated to the photodetector 1025 by the condenser lens 1024.

  The light detector 1025 includes a light detection cell 1025-1 and a light detection cell 1025-2, and a difference between signals I1 and I2 detected from the respective light detection cells 1025-1 and 1025-2 is obtained. Is input to the wobble signal detector 135 shown in FIG. The optical head shown in FIG. 74 can detect both a wobble signal and a push-pull track deviation detection signal.

  In the detection signal (and its detection circuit) shown in FIG. 74, the difference between I1 and I2 is taken as a track deviation detection signal, but in the detection signal (and its signal detection circuit) shown in FIG. Are added by the adder 1126 to detect the signal (I1 + I2). FIG. 70B shows a signal waveform detected at (I1 + I2). FIG. 70B shows the detection signal level of the reproduction signal when the focused spot by the objective lens 1128 of the optical head shown in FIG. 70A is irradiated on each area on the information storage medium 1101. Yes. As shown in FIG. 23C, in the write-once information storage medium of this embodiment, the system lead-in area SYLDI is an embossed pit area 211, and embossed pits are formed everywhere. Therefore, in the system lead-in area SYLDI, a reproduction signal from an emboss pit as shown in FIG. 70 (b) is obtained. Here, the highest detection signal level in the system lead-in area SYLDI is defined as I11HP.

  In the present embodiment, “light reflectance” is defined using a detection signal level detected using an optical head as follows.

  First, a parallel laser beam having an incident light amount IO is irradiated onto a specific region such as a prepit or a pregroove of the information storage medium 1101 that has no minute unevenness, and the reflected light amount IR of the parallel laser light reflected from the information storage medium 1101 is measured. Thus, the value of Rs = IR / IO is used as a reference for the light reflectance Rs. The value measured without using the optical head in this way is defined as the calibrated light reflectance Rs. Next, the detection signal level detected using the optical head in the predetermined area is set as the reflected light power Ds, and the value of (Rs / Ds) is detected using the optical head at each position of the information storage medium 1101. This is used as a conversion coefficient for converting the signal level into “light reflectance”. That is, the detection signal level output from the adder 1126 when the predetermined area is reproduced by the optical head shown in FIG. 70A is measured as the reflected light power Ds. For example, the optical head moves into the system lead-in area SYLDI, and the level I11HP having the highest detection signal level among the detection signal levels of the adder 1126 obtained there is measured, and the value of (Rs / Ds) × I11HP is calculated. The reflectance in the lead-in area SYLDI is defined as I11HP.

  In this embodiment, the reflectance of the information recording medium is defined so that the light reflectance of the system lead-in area SYLDI of the “H → L” recording film is 16% or more and 32% or less. There is. As shown in FIG. 23C, there is a connection area CNA formed on the mirror surface 210 adjacent to the system lead-in area SYLDI formed in the embossed area 211. The light reflectance when the focused spot focused by the objective lens 1128 of the optical head shown in FIG. 70A moves to the connection area CNA has no embossed pits. become. Next, a data lead-in area DTLDI exists adjacent to the connection area CNA. The data lead-in area DTLDI, the data area DTA, and the pre-groove area 214 of the data lead-out area DTLDO (FIG. 23C) Pregroove exists. On this pre-groove area 214, the detection signal level when the track loop is turned ON becomes the (Iot) groove level shown in FIG. 70 (b). When a recording mark is formed on the pre-groove, the light reflection amount decreases at the recording mark in the “H → L” recording film, so that the detection signal of the recording film is shown in FIG. Level drops below (Iot) groove level. A region having the highest detection signal level in the area where the recording mark is recorded is defined as I11HM. The light reflectance in the groove region 214 is also defined by (Rs / Ds) × I11HM as described above. The light reflectance of the place where the recording mark is formed in the “H → L” recording film of this embodiment is defined to be 14% or more and 28% or less. Further, the ratio (Iot) groove / I11HP of the light reflection amount (Iot) groove in the unrecorded area to the reflectance I11HP in the system lead-in area SYLDI in the “H → L” recording film in the present embodiment is 0.5 or more and 1 It is specified at a high level so as to fall within a range of 0.0 or less. In this embodiment, as shown in FIGS. 6B and 6C, by making the width Wg of the groove region 11 smaller than the width Wl of the land region 12, as shown in FIG. 70B, (Iot) groove There is a big technical feature at the higher level. Particularly in the “H → L” recording film, as shown in FIG. 6B or FIG. 6C, by increasing the thickness Dg of the recording layer 3-2, the step amount Hr between the groove and the land region is reduced. As a result, the level of (Iot) groove is increased so that the value of (Iot) groove / I11HP is 50% or more. As a result, the light reflection amount (I11HM) from the recording mark recorded in the groove area 11 can be increased, and the detection signal amplitude from the recording mark on the groove area 11 is increased.

  Next, the detection signal level in the “L → H” recording film will be described with reference to FIG. The optical head structure and detection signals (signal detection method and detection circuit) shown in FIG. 71A are exactly the same as those shown in FIG. The amount of light reflection in the system lead-in area SYLDI in the “L → H” recording film is defined as (Rs / Ds) × I11HP as in the “H → L” recording film. In the present embodiment, the light reflectance in the system lead-in area SYLDI in the “L → H” recording film is defined as 14% or more and 28% or less. In the “L → H” recording film, the thicknesses Dg and Dl of the recording film 3-2 in the pre-groove area 11 and the land area 12 shown in FIGS. 6B and 6C are relatively thin. Therefore, the detection signal level (Iot) groove of the unrecorded area in the pre-groove area 214 when the track loop is ON in the unrecorded area is lower than the “H → L” recording film shown in FIG. As a result, in this embodiment, the ratio of the light reflection amount (Iot) groove on the pre-groove area 214 at the unrecorded position in the data lead-in area DTLDI or data area DTA and data lead-out DTLDO (Iot) groove / I11HP Is set lower than the “H → L” recording film so as to fall within the range of 40% to 80%. In the “L → H” recording film, the light reflectance in the recording mark increases more than the reflectance in the unrecorded area, so that it has a reproduction signal waveform as shown in FIG. Also in FIG. 71 (b), the light reflection amount uses the place (I11HM) where the detection signal level of the reproduction signal from the recording mark is the highest, and the reflectance is defined by (Rs / Ds) × I11HM. In this embodiment, the reflectance in the “L → H” recording film is set to 14% or more and 28% or less.

  FIG. 72 collectively shows detection signal levels in the “L → H” recording film and the “H → L” recording film shown in FIGS. 70 and 71.

  The present embodiment is characterized in that the light reflectance range in the system lead-in area SYLDI is defined so as to partially overlap the “L → H” recording film and the “H → L” recording film. There is an overlapping portion α of the light reflectance between the “H → L” recording film and the “L → H” recording film in the system lead-in area SYLDI of FIG. 72, and in this embodiment, the light reflectance range of this area Is from 16% to 28%. In this embodiment, as a method of overlapping the reflectance ranges of the “H → L” recording film and the “L → H” recording film in the system lead-in area SYLDI, the system is controlled by controlling the optical characteristics of each recording layer 3-2. In the lead-in area SYLDI, an overlapping portion of the reflectance of the “H → L” recording film and the “L → H” recording film is formed. Further, in the present embodiment, as shown in FIG. 72, there is also an overlapping portion β of the light reflectance range when the track loop is ON in the data lead-in area DTLDI or data area DTA and the data lead-out area DTLDO. As shown in FIG. 70 (b), the overlapping portion shows the (Iot) groove level in the unrecorded area in the “H → L” recording film as the unrecorded area in the “L → H” recording film shown in FIG. 71. The detection signal level (Iot) is higher than the signal level of the groove so that there is an overlapping part β of the light reflectivity of the two. Specifically, as shown in FIG. 6, the thicknesses Dg and Dl of the recording layer 3-2 are set so that the “H → L” recording film is thicker than the “L → H” recording film. Yes. As a result, the step Hr in the light reflection layer 4-2 in the “H → L” recording film is smaller than the “L → H” recording film, and as a result, the unrecorded area in the “H → L” recording film is detected. Increases signal level (Iot) groove. In the present embodiment, as shown in FIG. 72, the light reflectance range when the track loop is ON is not only that the “H → L” recording film and the “L → H” recording film match, but also within the data area DTA. The overlapping portion β of the light reflectance between the “H → L” recording film and the “L → H” recording film is maximized. Furthermore, in the present embodiment, there is a portion γ where the light reflectance overlaps between the portion α where the light reflectance in the SYLDI in the system lead-in region overlaps and the portion β where the light reflectance in the data region DTA overlaps. I am doing so. In the information recording / reproducing apparatus or information reproducing apparatus of this embodiment, as shown in FIG. 11 or FIG. 13, the same preamplifier circuit 304 is used, and the reproduction signal in the system lead-in area SYLDI and the reproduction signal in the data area DTA are used. Is detected. When the maximum value level of the detection signal that can be detected stably by the preamplifier 304 is in the range of 5% to 50%, it can be detected stably. Therefore, the range of all the light reflectances is set to be in the range of 5% to 50% in accordance with the characteristics of the preamplifier 304. As a result, since a single preamplifier can be used for signal detection in the system lead-in area SYLDI and the data read area DTA, the cost of the information recording / reproducing apparatus or information reproducing apparatus can be reduced. In this embodiment, as shown in FIG. 72, a portion γ where the light reflectance overlaps between the portion α where the light reflectance overlaps in the system lead-in area SYLDI and the portion β where the light reflectance overlaps in the data area DTA is defined. The signal is increased so that the signal from the preamplifier 304 can be detected more stably. In this embodiment, as shown in FIG. 6B or FIG. 6C, the width Wg of the pre-groove area 11 is made larger than Wl of the land area 12, and the detection signal from the groove in the unrecorded area such as the data area DTA is detected. By reducing the level (Iot) groove, the overlapping portion γ of the light reflectance between α and β is increased.

5-2) Characteristics of Optical Absorption Spectra Regarding “L → H” Recording Film of this Embodiment “3 → 4” Characteristics of “H → L” Recording Film ”“ H → L ” “In the recording film, the relative absorbance in the unrecorded area is basically low, so that when the reproducing light is irradiated during reproduction, the optical characteristic change caused by absorbing the energy of the reproducing light hardly occurs. Even if the optical characteristics change (update of recording action) occurs due to absorption of the energy of the reproduction light in the recording mark having a high absorbance, the light reflectance from the recording mark is decreasing, so the amplitude of the reproduction signal (I11≡ I11H-I11L) increases, and there is little adverse effect on the reproduction signal processing.

  In contrast, the “L → H” recording film has an optical characteristic that “the light reflectance of the unrecorded portion is lower than that in the recording mark”. This means that the absorbance of the unrecorded portion is higher than that in the recorded mark, as can be seen from the contents described with reference to FIG. Therefore, the “L → H” recording film is more susceptible to signal degradation during reproduction than the “H → L” recording film. As described in “3-2-B] Basic features common to organic dye recording materials in the present embodiment”, “ε” is prepared in the event that reproduction signal deterioration occurs due to irradiation with ultraviolet rays or reproduction light. There is a need to improve the reliability of playback information.

  As a result of examining the characteristics of organic dye recording materials in detail, it was found that the mechanism that changes the optical characteristics by absorbing the energy of the reproduction light is almost similar to the mechanism that changes the optical characteristics by ultraviolet irradiation. As a result, if a structure for improving durability against ultraviolet irradiation in an unrecorded area is provided, signal deterioration during reproduction becomes difficult to occur. Therefore, in the “L → H” recording film, the feature of this embodiment is that the value of λmax write (maximum absorption wavelength closest to the wavelength of recording light) is longer than the wavelength of recording light or reproducing light (near 405 nm). There is. Thereby, the absorptance with respect to an ultraviolet-ray can be made low, and the durability with respect to ultraviolet irradiation can be improved significantly. As can be seen from FIG. 21, the difference in absorbance between the recorded part and the unrecorded part in the vicinity of λmax write is small, and the reproduction signal modulation degree (signal amplitude) when reproducing with the wavelength light in the vicinity of λmax write is small. . Taking into account the wavelength variation of the semiconductor laser light source, it is desirable that a sufficiently large reproduction signal modulation degree (signal amplitude) can be obtained in the range of 355 nm to 455 nm. Therefore, in this embodiment, the recording film 3-2 is designed so that the wavelength of λmax write is outside the range of 355 nm to 455 nm (that is, longer wavelength side than 455 nm).

An example of the light absorption spectrum in the “L → H” recording film in this embodiment is shown in FIG. As described in “5-1) Characteristic description regarding“ L → H ”recording film” in this embodiment, in this embodiment, the light reflection of the non-recording portion (“L” portion) of the “L → H” recording film is described. The lower limit value β of the rate is set to 18%, and the upper limit value γ is set to 32%. In order to satisfy the above condition from 1−0.32 = 0.68, the absorbance value Al405 in the unrecorded area at 405 nm is Al405 ≧ 68% (36)
You can intuitively understand that you should be satisfied. Although the light reflectance at 405 nm of the light reflecting layer 4-2 in FIG. 1 is slightly lower than 100%, it is assumed that it is close to 100% for the sake of simplicity of explanation. Therefore, the light reflectance when the absorbance Al = 0 is almost 100%. In FIG. 20, the light reflectance of the entire recording film at a wavelength of λmax write is represented by Rλmax write. The formula (36) is derived on the assumption that the light reflectance at this time is zero (Rλmax write≈0). However, since it is not actually “0”, it is necessary to derive a more strict formula. The strict conditional expression for setting the upper limit value γ of the light reflectance of the non-recording portion (“L” portion) of the “L → H” recording film to 32% is 1-Al405 × (1-Rλmax write) ≦ 0.32. (37)
Given in. All conventional write-once information storage media use “H → L” recording film, and there is no accumulation of information regarding “L → H” recording film, but “5-3) anion portion: azo metal complex + cation. Part: Dye ”and“ 5-4) Azo metal complex + “Use copper” as the central metal. When this embodiment described later is used, the most severe condition satisfying the expression (37) is Al405 ≧ 80% (38 )
It becomes. When the organic dye recording material described later in the above embodiment is used, when the recording film is optically designed including a margin such as a variation in characteristics during manufacturing and a change in thickness of the recording layer 3-2, "5-1). As the minimum condition that satisfies the reflectance described in the “characteristics relating to“ L → H ”recording film” in the present embodiment, Al405 ≧ 40% (39)
I understood that I should be satisfied. Furthermore, Al355 ≧ 40% (40)
Al455 ≧ 40% (41)
Is satisfied even if the wavelength of the light source is changed in the range of 355 nm to 405 nm or in the range of 405 nm to 455 nm (in the case of satisfying both equations at the same time), Reproduction characteristics can be secured.

  FIG. 21 shows a change state of the light absorption spectrum after recording in the “L → H” recording film of the present embodiment. The value of the maximum absorption wavelength λlmax within the recording mark is deviated from the wavelength of λmax write, and it is considered that an intermolecular molecular change (for example, an azo metal complex changes in sequence) occurs. Further, the decolorization effect (local electron orbital cutting (local electron orbital cutting (localization)) is observed in parallel with the decrease in both the absorbance at λlmax and the absorbance at 405 nm, Al405, and the spread of the light absorption spectrum itself. Dissociation of molecular bonds)).

Also in the “L → H” recording film of the present embodiment, the “L → H” recording film and the “H → L” recording are satisfied by satisfying the equations (20), (21), (22), and (23). The same signal processing circuit can be used for both membranes to simplify the signal processing circuit and reduce the price. In the equation (20), I11 / I11H≡ (I11H−I11L) /I11H≧0.4 (42)
I11H ≧ / I11L / 0.6 (43)
It becomes. As already described, in this embodiment, the lower limit value β of the light reflectance of the unrecorded portion (“L” portion) of the “L → H” recording film is set to 18%, and this value corresponds to I11L. . Furthermore, conceptually I11H≈1-Ah405 × (1-Rλmax write) (44)
Therefore, from the equations (43) and (44), 1−Ah405 × (1−Rλmax write) ≧ 0.18 / 0.6 (45). When 1−Rλmax write≈0, equation (45) is Ah405 ≦ 0.7 (46)
It is obtained by. Comparing the above formulas (46) and (36), it can be seen that it would be good to set the values of Al405 and Ah405 around 68% to 70% as absorbance values. Furthermore, when considering the case where the value of Al405 falls within the range of equation (39) and the performance stability of the signal processing circuit, the severe conditions are Ah405 ≦ 0.4 (47)
There is. If possible, Ah405 ≦ 0.3 (48)
It is desirable to satisfy

5-3) Anion part: azo metal complex + cation part: Dye “5-1) Features described in“ Characteristics of “L → H” recording film ”in this embodiment”, “5-2) This implementation The organic dye material according to the present embodiment, which satisfies the conditions indicated by the “characteristics of the light absorption spectrum related to the“ L → H ”recording film” in the embodiment, will be described. The thickness of the recording layer 3-2 satisfies the conditions indicated by the equations (3), (4), (27), and (28) and is formed by spinner coating (spin coating). As an example for comparison, “salt” crystals are assembled with an “ionic bond” between a positively charged “sodium ion” and a negatively charged “chlorine ion”. Similarly, in the case of polymers, organic dye materials may be formed by combining a plurality of different polymers close to “ionic bonds”. The organic dye recording film 3-2 in the present embodiment is composed of a “cation part” that is charged on the plus side and an “anion part” that is charged on the minus side. In particular, the “cation part” charged on the positive side uses a “dye” that has coloring properties, and the counter ion part is used and the “anion part” that is negatively charged uses an organometallic complex to stabilize the binding. To stabilize the electronic structure in the “δ” color development region shown in “3-2-B] Basic features common to the organic dye recording material in the present embodiment” There is a major technical feature in satisfying the condition of “structural decomposition is difficult to occur”. Specifically, in this embodiment, an “azo metal complex” having a general structural formula shown in Chemical Formula 1 is used as an organometallic complex. In this embodiment comprising a combination of an anion portion and a cation portion, cobalt or nickel is used as the central metal M of this azo metal complex to improve the light stability, but not limited to scandium, yttrium, titanium, zirconium, hafnium. , Vanadium, niobium, tantalum, chromium, molybdenum, tungsten, manganese, technetium, rhenium, iron, ruthenium, osmium, rhodium, iridium, palladium, platinum, copper, silver, gold, zinc, cadmium, mercury, etc. may be used. . In the present embodiment, any one of a cyanine dye having a general structural formula shown in Chemical Formula 2, a styryl dye having a general structural formula shown in Chemical Formula 3, and a monomethine cyanine dye having a general structural formula shown in Chemical Formula 4 is used as a dye used in the cation moiety. Use.

  In the present embodiment, an azo metal complex is used for the anion portion. However, for example, a formazan metal complex having a general structural formula shown in Chemical Formula 5 may be used.

  The organic dye recording material comprising the anion portion and the cation portion is initially powdered. In the case of forming the recording layer 3-2, this powdery organic dye recording material is dissolved in an organic solvent, and then spin coating is performed on the transparent substrate 2-2. Examples of organic solvents used at this time include hydrocarbons such as fluoroalcohol-based TFP (tetrafluoropropanol), pentane, hexane, cyclohexane, petroleum ether, petroleum benzine, alcohols, phenols, ethers, nitriles, nitro Either a compound or a sulfur-containing compound or a combination thereof is used.

5-4) Use of “copper” as the azo metal complex + central metal Recording on the “H → L” recording film and the “L → H” recording film using the optical characteristic change of this embodiment as a recording principle (record mark formation) An example of the change in the light absorption spectrum before and after is shown in FIGS. Λmax write wavelength before recording (in an unrecorded area) is λbmax write, and the half-value width of the light absorption spectrum (b) centered on this λbmax write (absorbance A at λbmax write is “1”. The width of the wavelength region satisfying the range of ≧ 0.5 ″ is defined as Was, and the λmaxwrite wavelength of the light absorption spectrum (a) after recording (within the recording mark) is defined as λamaxwrite. The recording film 3-2 having the characteristics shown in FIGS. 40 and 41 is the same as the recording principle shown in [α] in “3-2-B] Basic features common to the organic dye recording material in this embodiment”. , "Changes in the electronic structure (electron orbital) for electrons contributing to the coloring phenomenon" and "Molecular structure changes in the molecule" are used. When “change in electronic structure (electron orbit) with respect to electrons contributing to the color development phenomenon” occurs, for example, the size and structure of the color development region 8 as shown in Chemical Formula 1 change. For example, when the dimension of the light emitting region 8 changes, the resonance absorption wavelength of the localized electrons changes, so the maximum (maximum) absorption wavelength of the light absorption spectrum changes from λbmax write to λamax write. Similarly, when a “molecular structure change within the molecule” occurs, the structure of the color development region 8 also changes, and similarly, the maximum (maximum) absorption wavelength of the light absorption spectrum changes. Here, if the change amount of the maximum (maximum) absorption wavelength is defined as Δλmax, Δλmax≡ | λamax write−λbmax write | (49)
The relationship holds. Thus, when the maximum (maximum) absorption wavelength of the light absorption spectrum changes, the half-value width Was of the light absorption spectrum also changes accordingly. The influence on the reproduction signal obtained from the recording mark position when the maximum (maximum) absorption wavelength of the light absorption spectrum and the half-value width Was of the light absorption spectrum simultaneously change will be described. In FIG. 40 (FIG. 41), since the light absorption spectrum in the pre-recording / unrecorded area is given by (b), the absorbance at 405 nm reproduction light is Ah405 (Al405). If only the maximum (maximum) absorption wavelength of the optical spectrum after recording (in the recording mark) changes to λamax write, and there is no change in the half-value width Was, the optical absorption spectrum of FIG. c), the absorbance at 405 nm reproduction light changes to A * 405. However, since the half-value width actually changes, the absorbance after recording (in the recording mark) becomes Al405 (Ah405). . Since the change amount of absorbance before and after recording | Al405-Ah405 | is proportional to the reproduction signal amplitude value, in the example shown in FIG. 40 (FIG. 41), the maximum (maximum) absorption wavelength change and the half-value width change increase the reproduction signal amplitude. This causes a problem of deteriorating the C / N ratio of the reproduction signal. As a first application example of this embodiment for solving the problem, the characteristics of the recording layer 3-2 are set so that the maximum (maximum) absorption wavelength change and the half-value width change work synergistically with the increase in the reproduction signal amplitude. There is a big feature in the setting (film design). That is, as can be easily predicted from the change in FIG. 40 (FIG. 41), in the “H → L” recording film, the full width at half maximum is expanded regardless of the moving direction of λamax write after recording with respect to λbmax write before recording,
In the “L → H” recording film, the characteristics of the recording layer 3-2 are set (film design) so that the half-value width is changed in a direction that becomes narrower regardless of the moving direction of the λamax write after recording with respect to the λbmax write before recording. .

Next, a second application example in the present embodiment will be described. As described above, there is a case where the C / N ratio of the reproduction signal is lowered by canceling the opening between Ah 405 and Al 405 due to the change in the maximum (maximum) absorption wavelength and the change in half-value width Was. Furthermore, in the first application example and the embodiment shown in FIG. 40 or 41, the change in the maximum (maximum) absorption wavelength and the half-value width Was of the light absorption spectrum change simultaneously, so that after recording (in the recording mark). The value of absorbance A is affected by both the maximum (maximum) absorption wavelength variation Δλmax and the half-value width variation. When the write-once information storage medium 12 is mass-produced, it is difficult to accurately control both the maximum (maximum) absorption wavelength change Δλmax and the half-value width change at the same time. Variation in the reproduction signal amplitude when recording is increased, and the reliability of the reproduction signal when reproduced by the information reproducing apparatus shown in FIG. 9 is lowered. In contrast, the material of the recording layer 3-2 shown in the second application example in the present embodiment is devised so that the maximum (maximum) absorption wavelength before and after recording (in the recording mark and in the unrecorded area) does not change. There is a great feature in that the reliability of the reproduction signal is improved by suppressing the variation in the value of the absorbance A after recording (within the recording mark) and reducing the inter-individual variation in the reproduction signal amplitude therefrom. In this second application example, since the maximum (maximum) absorption wavelength before and after recording (in the recorded mark and in the unrecorded area) does not change, the value of the absorbance A is the light before and after recording (in the recorded mark and in the unrecorded area). It is determined only by the spread of the absorption spectrum. When a large number of write-once information storage media 12 are mass-produced, it is only necessary to control the spread of the light absorption spectrum before and after recording (in the recorded mark and in the unrecorded area), so that variations in characteristics between the media can be reduced. Even if it is devised so that the maximum (maximum) absorption wavelength before and after recording (in the recorded mark and in the unrecorded area) does not change, strictly, the values of λbmax write and λamax write are completely set as shown in FIG. It is difficult to match. The full width at half maximum Was of the light absorption spectrum centering on λbmax write shown in FIGS. 40 and 41 is often in the range of 100 nm to 200 nm in a general organic dye recording material. Therefore, when the value of the maximum (maximum) absorption wavelength change Δλmax exceeds 100 nm, the absorbance Ah405 (Al405) obtained from the characteristic (b) and the absorbance A * 405 obtained from the characteristic (c) are greatly increased. It can be easily predicted from FIG. 40 and FIG. Therefore, as a second application example, the meaning of “the maximum (maximum) absorption wavelength does not change” means Δλmax ≦ 100 nm (50)
It means satisfying the conditions. Furthermore, the maximum (maximum) absorption wavelength variation Δλmax is 1/3 of the equation (50).
Δλmax ≦ 30nm (51)
The difference between the absorbance Ah405 (Al405) obtained from the characteristics of (b) and the absorbance A * 405 obtained from the characteristics of (c) becomes very small under the conditions of (b), and the reproduction signal characteristics between the media when mass-produced The looseness can be reduced.

  FIG. 43 shows “L → H” recording film characteristics satisfying the formula (50) or the formula (51). The light absorption spectrum before recording (in an unrecorded area) is a broad spectrum as shown in the characteristic (b) of FIG. 43, and the absorbance Ah405 at a reproduction wavelength of 405 nm is a sufficiently small value. The light absorption spectrum after recording (within the recording mark) becomes narrow as shown in the characteristic (a) of FIG. 43, and the absorbance Al405 at the reproduction wavelength of 405 nm increases.

  In order to satisfy the formula (50) or the formula (51), in the present embodiment, “3-2-B” in “α” in “Basic features common to the organic dye recording material in the present embodiment” “Changes in orientation within the molecule” The specific contents of this embodiment (second applied example) will be described below. In the azo metal complex shown in Chemical Formula 1, since the benzene nucleus ring is radically bonded, a plurality of benzene nucleus rings are arranged on the same plane. That is, the four benzene nucleus rings above the central metal M in the chemical formula 1 form a U (up side) plane formed by the benzene nucleus group, and the four benzene nucleus rings below the central metal M. Forms the D (down side) plane created by the benzene nucleus group. In any case (regardless of before and after recording), the U plane and the D plane always maintain a parallel relationship. The side chain groups of R1 and R3 are arranged so as to be orthogonal to the U plane and the D plane. The central metal atom M and the oxygen atom O (solid line portion) are connected by an ionic bond, and the plane formed by the line connecting O-MO is arranged in parallel to the U plane and the D plane. . The coloring area 8 surrounded by the round area of Chemical Formula 1 has such a three-dimensional structure. For future explanation, the direction from the R4 direction to the R5 direction in the U plane is provisionally defined as “Yu direction”, and the direction from the R4 direction to the R5 direction in the D plane is provisionally defined. It is defined as “Yd direction”. The nitrogen atom N included in the U plane or D plane and the central metal atom M sandwiched between the two surfaces (broken line portion) are connected by a coordinate bond, and nitrogen centered on the central metal atom M The position of atom N is rotatable. In other words, the Y plane can be rotated with respect to the Yu direction while maintaining a parallel relationship between the U plane and the D plane. In the azo metal complex shown in Chemical Formula 1, the Yu direction and the Yd direction are parallel to each other as shown in FIG. 42 (a) (the directions can be opposite or the same as in FIG. 42 (a)). As shown in FIG. 42B, the Yu direction and the Yd direction are twisted with each other. Naturally, an arbitrary angular relationship between FIG. 42 (a) and FIG. 42 (b) is obtained. As described above, since the side chain groups of R1 and R3 shown in Chemical Formula 1 are arranged so as to be orthogonal to the U plane and the D plane, the upper and lower R1 or R3 of the structure in FIG. Collisions easily occur between side chain groups or other side chain groups such as R4. Therefore, when the Yu direction and the Yd direction are twisted with each other as shown in FIG. 42B (when viewed from the upper side of the U plane, the Yu direction and the Yd direction appear to be orthogonal to each other). Is the most structurally stable. The light absorption wavelength in the color developing region 8 in the state of FIG. 42B matches the value of λamax write = λbmax write in FIG. When the relationship between the Yu direction and the Yd direction deviates from the state shown in FIG. 42B, the electronic structure in the coloring region 8 and the localized distance of the light-absorbing electrons (the size of the local region) change slightly, and the light absorption wavelength Deviates from the value of λamax write = λbmax write. The relationship between the Yu direction and the Yd direction is arbitrarily oriented in the recording layer 3-2 immediately after being formed on the transparent substrate 2-2 by spinner coating (unrecorded state). Therefore, as shown in the characteristic (b) in FIG. 43, the distribution width of the light absorption spectrum is wide. When the temperature in the recording layer 3-2 is locally increased to form a recording mark, the molecular orientation starts to move due to the high temperature, and finally the state shown in FIG. As a result, the electronic structure in the coloring region 8 is consistent everywhere in the recording mark, and changes to a light absorption spectrum having a narrow distribution width as shown in the characteristic (a) of FIG. As a result, the absorbance at the reproduction wavelength (for example, 405 nm) changes from Al405 to Ah405.

  Another effect of using the color development region 8 in the azo metal complex as shown in Chemical Formula 1 will be described. When the combination of the anion part and the cation part described above is used, a dye is used for the cation part. The coloring area in each dye shown in Chemical Formula 2 to Chemical Formula 4 occupies a part in each dye structure, but by combining with the anionic part that does not contribute to the coloring area, the relative color development area in the recording layer 3-2 The occupied volume is reduced. As a result, the light absorption cross-sectional area is relatively reduced and the molar absorption coefficient is decreased. As a result, the absorbance value at the λmax write position shown in FIG. In contrast, when utilizing the color development characteristics around the central metal of the azo metal complex described here, the azo metal complex itself emits light, so there is an extra portion that does not contribute to the color development region such as the anion portion described above. not exist. Therefore, there is no unnecessary factor for reducing the relative occupied volume of the coloring region, and the occupied volume of the coloring region 8 in the azo metal complex is wide as shown in Chemical Formula 1, so that the light absorption cross-sectional area is increased and the molar molecule is increased. The extinction coefficient value increases. As a result, the absorbance at the λmax write position shown in FIG. 20 is increased, and the recording sensitivity is improved.

  The electronic structure in the “δ” color development region described in “3-2-B] Basic features common to the organic dye recording material in the present embodiment” is stabilized, and structural decomposition against ultraviolet rays and reproduction light irradiation hardly occurs. As a specific method for achieving this, the main feature of the present embodiment is that the central metal of the azo metal complex is optimized to stabilize the structure of the color development region.

It is known that each metal ion has a unique ionization tendency characteristic. When these metal atoms are arranged in the order of strong ionization tendency, Na>Mg>Al>Zn>Fe>Ni>Cu>Hg>Ag> Au
It has become. This ionization tendency of metal atoms represents the “characteristic that metal emits electrons and becomes cations”.

  Various metal atoms were inserted as the central metal of the azo metal complex having the structure shown in Chemical Formula 1 and the stability of repeated reproduction (the stability of the color development characteristics when repeatedly irradiated with light at around 405 nm with the reproduction power) was investigated. As a result, it was found that the higher the ionization tendency of the metal atom, the more electrons are emitted, the bond is broken, and the colored region 8 is easily destroyed. As a result of numerous experiments, it has been found that it is desirable to use a metal material (Ni, Cu, Hg, Ag, Au) after nickel (Ni) as the central metal in order to ensure the structural stability of the color development region. Furthermore, it is most desirable to use copper (Cu) as the central metal in the present embodiment from the viewpoints of “high structural stability of the color development region”, “cost reduction”, and “use safety”. In the present embodiment, any one of CH3, CxHy, H, Cl, F, NO2, and SO2NHCH3 is used as R1, R2, R3, R4, and R5 that are side chains of Chemical Formula 1.

  Next, a method for forming the organic dye recording material having the molecular structure shown in Chemical Formula 1 as the recording layer 3-2 on the transparent substrate 2-2 will be described. First, 1.49 g of the organic dye recording material in powder form is dissolved in 100 ml of TFP (tetrafluoro-propanol) which is a fluorine alcohol solvent. The above numerical value means that the mixing ratio is 1.4% by weight, and the actual usage varies depending on the production amount of the write-once information storage medium. The mixing ratio is desirably 1.2 to 1.5% by weight. As a solvent, it is an indispensable condition not to dissolve the surface of the transparent substrate 2-2 made of a polycarbonate resin, and the above alcohol is used. Since TFP (tetrafluoro-propanol) has polarity, the solubility of the organic dye recording material in powder form is improved. The organic dye recording material dissolved in the solvent is applied to the center of the transparent substrate 2-2 while rotating the transparent substrate 2-2 on the spindle motor, and the solvent evaporates after spreading using centrifugal force. After that, the recording layer 3-2 is hardened by a baking process for raising the entire temperature.

  FIG. 44 shows a third application example in which the basic principle of the second application example in this embodiment is also applied to the “H → L” recording film. The maximum (maximum) absorption wavelength λamax write of the absorption spectrum (a) after recording (within the recording mark) with respect to the maximum (maximum) absorption wavelength λbmax write of the absorption spectrum (b) before recording (in the unrecorded area). Make equal. As an example of a specific organic dye material for realizing the third application example, an azo metal complex is used for the anion portion, and the cation portion has a wavelength shorter than the reproduction signal wavelength (for example, 405 nm) as shown in FIG. An “anionic / cationic organic dye recording material” using dye molecules having an absorption wavelength λbmax write on the side is used. In this case, in the azo metal complex shown in Chemical Formula 1, dye molecules (α or γ position in the D plane formed by the benzene nucleus group and the β or δ position in the U plane formed by the benzene nucleus group by an interionic force are used. A positively charged cation portion) is disposed. The maximum (maximum) absorption wavelength λbmax write of the light absorption spectrum (b) before recording (in the unrecorded area) and the maximum (maximum) absorption wavelength λamax write of the light absorption spectrum (a) after recording (within the recording mark). The principle of changing (recording) the light absorption spectrum before and after recording while keeping unchanged is the same as in the second application example, the U plane (Yu direction) created by the benzene nucleus group and the D plane (Yd) created by the benzene nucleus group. Use rotation between (direction). Furthermore, in the third application example, the electron binding force in the color development region 8 is improved to make it difficult for “deterioration of the electronic structure (electron orbit) to electrons contributing to the color development phenomenon” such as decolorization. As a result, the area in the absorption spectrum (b) before recording (in the unrecorded area) (the integration result in the wavelength direction of the spectrum) matches the area in the absorption spectrum (a) after recording (in the recording mark). I can do it. Thus, the absorbance A at the maximum (maximum) absorption wavelength λamax write in the absorption spectrum (a) after recording (within the recording mark) is the absorbance at the maximum (maximum) absorption wavelength λbmax write before recording (in the unrecorded area). It becomes larger than “1”, and the value of Al 405 rises from the value of Ah 405 as shown in FIG.

If there is no deterioration in the coloring region 8 such as decolorization, the area in the absorption spectrum before and after recording (integration result in the wavelength direction of the spectrum) is kept unchanged. The absorbance Aamax at the maximum (maximum) absorption wavelength λamax write increases as the width decreases. The difference between the values of absorbance Al405 and Ah405 at the reproduction wavelength of 405 nm is clearly different (can be detected as a reproduction signal with good C / N ratio) as the value of absorbance Aamax at the maximum (maximum) absorption wavelength λamax write. ≧ 1.2 (52)
It can be seen from FIG. 44 that the above condition must be satisfied. Furthermore, in order to secure the reproduction reliability of the detection signal stably, Aamax ≧ 1.5 (53)
It is necessary to become. As an example of a specific organic dye recording material for realizing the third application example, an azo metal complex is used and a structure using a dye for the cation part is shown. The organic dye recording material is not limited to this and has “H → L” recording characteristics, and satisfies the formula (50) or (51) with respect to the maximum (maximum) absorption wavelength change amount before and after recording, and the maximum (maximum) ) An organic dye recording material in which the absorbance at the absorption wavelength changes is included in the invention (third application example).

  Further, a fourth application example is shown in FIG. In the phase change recording film, “atomic arrangement is aligned (crystalline state) before recording” and “atomic arrangement is random after recording (amorphous state)”. In the fourth application example, the characteristics of the phase change recording film are combined with the characteristics of “the maximum (maximum) absorption wavelength does not change before and after recording” shown in the second application example. As a specific organic dye recording material in the fourth application example, the azo metal complex shown in the third application example has a structure using a dye in the anion part and in the cation part. The structure or manufacturing method of the recording layer 3-2 is slightly different. That is, it takes time to solidify the recording layer 3-2 using an organic solvent that is difficult to evaporate after application of an organic dye recording material dissolved in an organic solvent on the transparent substrate 2-2 by spinner coating, Intramolecular (or intermolecular) orientation at the stage of solidification of the recording layer 3-2 by raising the temperature of the transparent substrate 2-2 in advance and slowly lowering the temperature of the transparent substrate 2-2 when the organic solvent evaporates. And devise so that the arrangement is easy to align. As a result, as shown in the characteristic (b) of FIG. 45, the width of the light absorption spectrum before recording (in the unrecorded area) becomes narrow. Next, devise how to give a recording pulse during recording (the recording layer 3-2 increases the height of the recording pulse when the same energy is applied so that it rapidly cools after exceeding the optical property change temperature locally) Instead, the recording pulse width is narrowed, etc., and the orientation and arrangement within the molecule (or between the molecules) after recording (within the recording mark) are made random. As a result, the width of the light absorption spectrum after recording (in the recording mark) is widened as shown in characteristic (a) of FIG. By adjusting the reproduction light wavelength to the base position of the light absorption spectrum, a large difference in absorbance A between before and after recording is produced. Although an example in which an azo metal complex is used as a specific organic dye recording material for realizing the fourth application example and a dye is used for the cation part in the anion portion is shown, a specific example for realizing the fourth application example is shown. The organic dye recording material is not limited to this and has “H → L” recording characteristics, satisfies the formula (50) or (51) with respect to the maximum (maximum) absorption wavelength change amount before and after recording, and the recording layer 3 -2 An organic dye recording material having regularity in the molecular arrangement of the unrecorded part (before recording) immediately after formation, but the molecular arrangement irregularity after recording (in the recording mark) is disclosed in the invention (fourth application example). included.

Chapter 6 Explanation on Pregroove Shape / Prepit Shape at the Interface of Coating Type Organic Dye Recording Film and Light Reflective Layer 6-1) Light Reflective Layer As described in “Chapter 0 Explanation of Relationship between Used Wavelength and This Embodiment” In the present embodiment, a range of 355 to 455 nm, particularly 405 nm, is considered. When the metal materials having high light reflectance in this wavelength band are arranged in descending order of light reflectance, Ag is about 96%, Al is about 80%, and Rh is about 80%. In the write-once information storage medium using the organic dye recording material, the reflected light from the light reflecting layer 4-2 is fundamental as shown in FIG. High characteristics are required. In particular, in the case of the “H → L” recording film of the present embodiment, the light reflectance in the unrecorded area is low. Therefore, when the light reflectance in the light reflecting layer 4-2 alone is low, particularly from the pre-pit (emboss) area. Therefore, it is essential that the light reflection layer 4-2 alone has a high light reflectance. Therefore, in this embodiment, a material centering on Ag (silver) having the highest reflectance in the wavelength band is used. As a material for the light reflecting layer 4-2, the problem of “atom easily moves” and “easy to corrode” occurs in silver alone. When another atom is added to the first problem and partly alloyed, the silver atom becomes difficult to move. As a first embodiment in which another atom is introduced, the material of the light reflection layer 4-2 is AgNdCu. Since AgNdCu is in a solid solution state, the reflectivity is slightly lower than that of a single silver state. In the second embodiment in which different atoms are introduced, the material of the light reflection layer 4-2 is made of AgPd, and the potential is changed to make it difficult to be electrochemically corroded. When the light reflection layer 4-2 is corroded due to silver oxidation or the like, the light reflectance is lowered. In the case of the organic dye recording film having the recording film structure shown in FIG. 1B and particularly the organic dye recording film shown in “Chapter 3 Feature Description of Organic Dye Recording Film in this Embodiment”, the recording layer 3- The light reflectance at the interface between the light reflecting layer 2 and the light reflecting layer 4-2 is very important. When corrosion occurs at this interface, the light reflectance decreases and the optical interface shape blurs, and the detection signal characteristics from the track deviation detection signal (push-pull signal), wobble signal, and pre-pit (emboss) area due to the reflected light there. to degrade. In particular, as shown in FIGS. 6B and 6C, when the width Wg of the pre-groove area 11 is larger than the land area width W1, a track deviation detection signal (push-pull signal) or a wobble signal is difficult to generate. The influence of the deterioration of the light reflectance at the interface between the recording layer 3-2 and the light reflecting layer 4-2 due to corrosion becomes large. In order to prevent the deterioration of the light reflectance at the interface, AgBi is used for the light reflecting layer 4-2 as the third embodiment. AgBi forms a very stable phase on the surface (the interface between the recording layer 3-2 and the light reflecting layer 4-2), thereby forming a very stable phase and preventing the deterioration of the light reflectance at the interface. . That is, when Bi (bismuth) is slightly added to Ag, Bi floats on the interface, and it oxidizes to form a very dense film (passive film) called bismuth oxide. There is a work to stop. This passive film is formed on the interface and forms a very stable phase, so there is no degradation of light reflectivity, and track deviation detection signal (push-pull signal), wobble signal, pre-pit (emboss) over a long period of time. Guarantees the stability of the detection signal characteristics from the region. In the wavelength band of 355 to 455 nm, silver alone has the highest light reflectivity, and the light reflectivity decreases as the amount of additional atoms added increases. Therefore, the addition amount of Bi atoms in AgBi in this embodiment is preferably 5 at% or less (at% means atomic percent, for example, there are 5 Bi atoms in 100 total atoms of AgBi. Is shown). When actually prepared and evaluated for properties, it was found that a passive film could be formed if the amount of Bi atoms added was 0.5 at% or more. Based on the evaluation result, the Bi atom addition amount in the light reflection layer 4-2 in the present embodiment is set to 1 at%. In this third embodiment, since only Bi atoms are added, the amount of added atoms can be reduced as compared with the first embodiment AgNdCu (adding two kinds of atoms of Nd and Cu in Ag), and AgBi is more effective than AgNdCu. Light reflectance can be increased. As a result, even when the “H → L” recording film of the present embodiment and the width Wg of the pre-groove area 11 are wider than the land area width Wl as shown in FIGS. Good track deviation detection signals (push-pull signals), wobble signals, and detection signals from pre-pit (emboss) areas can be obtained. The third embodiment is not limited to AgBi. In addition, AgMg, AgNi, AgGa, AgNx, AgCo, AgAl, or a ternary system containing the atoms described above may be used as a silver alloy for forming a passive film. The thickness of the light reflection layer 4-2 is set in the range of 5 nm to 200 nm. If the thickness is less than 5 nm, the light reflection layer 4-2 is not uniform and is formed in a land shape. Therefore, the thickness of the light reflection layer 4-2 is set to 5 nm. Since the AgBi film begins to penetrate to the back side when the thickness is 80 nm or less, the thickness is 80 nm to 200 nm, preferably 100 nm to 150 nm in the case of a single-sided recording layer, and the thickness is 5 nm to 15 nm in the case of a single-sided two recording layer. Set to the range.

6-2) Description of Prepit Shape at the Interface of Coating Type Organic Dye Recording Film and Light Reflecting Layer The H format of this embodiment has a system lead-in area SYLDI as shown in FIG. As shown in FIG. 46, information is recorded in advance in the form of prepits. The reproduction signal in this area matches the reproduction signal characteristics from the reproduction-only information storage medium, and the signal reproduction circuit in the information reproduction apparatus or information recording / reproduction apparatus shown in FIG. I also use it. The definition for the signal detected from this area is matched with the definition of “3-4)“ Characteristics relating to recording layer H → L ”in the present embodiment. That is, the reproduction signal amount from the space area 14 having a sufficiently long length (11T) is defined as I11H, and the reproduction signal from the prepit (emboss) area 13 having a sufficiently long length (11T) is defined as I11L. And the difference between them is I11≡I11H-I11L. In the present embodiment, the reproduction signal in this area is matched with the reproduction signal characteristic from the reproduction-only information storage medium. I11 / I11H ≧ 0.3 (54)
Desirably I11 / I11H> 0.5 (55)
And When the amplitude of the repetitive signal in the space region 14 with the 2T-length pre-pit (emboss) region 13 is I2, I2 / I11 ≧ 0.5 (56)
Desirably I2 / I11> 0.7 (57)
I have to.

The physical conditions for satisfying the above expression (54) or (55) will be described. As already described with reference to FIG. 1B, the signal characteristics from the pre-pits are mainly governed by the reflected light from the light reflecting layer 4-2. Therefore, the reproduction signal amplitude value I11 is determined by the step amount Hpr between the space region 14 and the pre-pit (emboss) region 13 in the light reflection layer 4-2. When optical approximation calculation is performed, the step amount Hpr is equal to the reproduction light wavelength λ and the refractive index n32 in the recording layer 3-2. I11∝sin2 {(2π × Hpr × n32) / λ} (58)
From equation (58), it can be seen that I11 is maximized when Hpr≈λ / (4 × n32). In order to satisfy the formula (54) or the formula (55), at least Hpr ≧ λ / (12 × n32) from the formula (58) (59)
Desirably Hpr> λ / (6 × n32) (60)
It is necessary to be satisfied. As described in “Chapter 0 Description of Relationship between Wavelength Used and This Embodiment”, λ = 355 nm to 455 nm is used in this embodiment, and “2-1) Difference in recording principle / recording film structure and reproduction. Since n32 = 1.4 to 1.9 as described in “Differences in basic concept regarding signal generation”, if this value is substituted into the equation (59) or (60), Hpr ≧ 15.6 nm (62)
Desirably, Hpr> 31.1 nm (63)
The level difference is made to satisfy the conditions. In the conventional write-once information storage medium, since the thickness of the recording layer 3-2 is small in the space area 14 as shown in FIG. 46B, a step at the interface between the light reflecting layer 4-2 and the recording layer 3-2. Was small, and the expression (62) was not satisfied. On the other hand, in the present embodiment, the relationship between the thickness Dg of the recording layer 3-2 in the pre-pit (embossed) region 13 and the thickness Dl of the recording layer 3-2 in the space region 14 is “3-2-E”. As a result of devising it so as to meet the conditions described in “Basic characteristics relating to thickness distribution of recording layer in FIG. 46”, a sufficiently large step Hpr satisfying the expression (62) or (63) is obtained as shown in FIG. I was able to secure it.

  In order to ensure sufficient resolution of the reproduction signal so as to satisfy the expression (56) or (57) in the present embodiment by performing the optical approximation as described above, as shown in FIG. The width (Wp) of the (emboss) area 13 is set to be less than half of the track pitch, so that the resolution of the reproduction signal from the pre-pit (emboss) area 13 can be increased.

6-3) Description of Pregroove Shape at Interface between Coating Type Organic Dye Recording Film and Light Reflecting Layer Chapter 7 Description of H Format The H format in the present embodiment will be described below.

FIG. 22 shows the structure and dimensions of the information storage medium in this embodiment. As an embodiment: "Reproduction-only information storage medium" that is read-only and cannot be recorded
・ "Recordable information storage medium" that can be recorded once only
・ "Rewritable information storage medium" that can be rewritten any number of times
The three types of information storage medium embodiments will be specified. As shown in FIG. 22, the three types of information storage media share most of the structure and dimensions. All three types of information storage media have a structure in which a burst cutting area BCA, a system lead-in area SYLDI, a connection area CNA, a data lead-in area DTLDI, and a data area DTA are arranged from the inner periphery side. A data lead-out area DTLDO is arranged on the outer peripheral portion except for the OPT type read-only medium. As will be described later, in the OPT type read-only medium, a middle area MDA is arranged on the outer periphery. In the system lead-in area SYLDI, information is recorded in the form of an emboss (pre-pit), and both the write-once form and the rewritable form are read-only (not recordable). In the read-only information storage medium, information is recorded in the form of emboss (pre-pit) in the data lead-in area DTLDI, whereas in the write-once and rewritable information storage medium, a recording mark is formed in the data lead-in area DTLDI. It is an area where new information can be added (rewritten in rewritable form). As will be described later, in the write-once and rewritable information storage media, the data lead-out area DTLDO has information recorded in the form of embossing (pre-pits) and an area where new information can be added (rewritable in the rewritable form). A dedicated area is mixed. As described above, the data area DTA, data lead-in area DTLDI, data lead-out area DTLDO, and middle area MDA shown in FIG. In the system lead-in area SYLDI and the system lead-out area SYLDO, a slice level detection method is used for reproducing the signals recorded therein. In this way, compatibility with the current DVD is ensured and reproduction is secured.

  Unlike the current DVD standard, in the embodiment shown in FIG. 22, the burst cutting area BCA and the system lead-in area SYLDI are separated in position without overlapping. By physically separating the two, it is possible to prevent interference between information recorded in the system lead-in area SYLDI and information recorded in the burst cutting area BCA at the time of information reproduction, and to reproduce information with high accuracy. It can be secured.

As another embodiment, there is a method of forming a fine concavo-convex shape in advance at the location where the burst cutting area BCA is arranged when an “L → H” recording film is used. This will be described later with reference to information on the polarity (identification of “H → L” or “L → H”) of the recording mark existing at the 192nd byte in Table 8. In this embodiment, the conventional “H → L” is used. In addition, “L → H” recording film is incorporated into the standard, and the selection range of the recording film is expanded to enable high-speed recording and supply of a low-cost medium. As will be described later, in this embodiment, the case of using an “L → H” recording film is also considered. Data (barcode data) recorded in the burst cutting area BCA is formed by locally performing laser exposure on the recording film. As shown in FIG. 23, since the system lead-in area SYLDI is formed by the embossed pit area 211, the reproduction signal from the system lead-in area SYLDI appears in a direction in which the amount of light reflection decreases compared to the light reflection level from the mirror surface 210. If the burst cutting area BCA is in the mirror surface 210 state and the “L → H” recording film is used, the reproduction signal from the data recorded in the burst cutting area BCA is from the mirror surface 210 (in an unrecorded state). It appears in a direction in which the amount of light reflection increases from the light reflection level. As a result, the position (amplitude level) of the maximum level and minimum level of the reproduction signal from the data formed in the burst cutting area BCA and the position (amplitude level) of the maximum level and minimum level of the reproduction signal from the system lead-in area SYLDI. ) And a large level difference will occur. As will be described later with reference to FIG. 23, the information reproducing apparatus or information recording / reproducing apparatus (1) reproduces information in the burst cutting area BCA → (2) information in the information data zone CDZ in the system lead-in area SYLDI. (3) Reproduction of information in the data lead-in area DTLDI (in the case of write-once or rewrite)
→ (4) Readjustment of playback circuit constants in the reference code recording zone RCZ (optimization)
(5) In order to perform processing in the order of reproduction of information recorded in the data area DTA or recording of new information, the reproduction signal amplitude level from the data formed in the burst cutting area BCA and the system lead-in area If there is a large step in the amplitude of the reproduced signal from SYLDI, there arises a problem that the reliability of information reproduction is lowered. In order to solve the problem, this embodiment is characterized in that when an “L → H” recording film is used as the recording film, a fine uneven shape is formed in advance in the burst cutting area BCA. . If a fine concavo-convex shape is formed in advance, the light reflection level is lower than the light reflection level from the mirror surface 210 due to the light interference effect before recording data (barcode data) by local laser exposure. Thus, the level difference between the reproduction signal amplitude level (detection level) from the data formed in the burst cutting area BCA and the reproduction signal amplitude level (detection level) from the system lead-in area SYLDI is greatly reduced, and the reliability of information reproduction is improved. It is improved, and the effect of facilitating the processing when shifting from (1) to (2) is produced. When the “L → H” recording film is used, there is a method of using the embossed pit area 211 as in the system lead-in area SYLDI as a specific content of the fine uneven shape formed in advance in the burst cutting area BCA. As another embodiment, there is a method of forming the groove area 214 or the land area and the groove area 213 in the same manner as the data lead-in area DTLDI and the data area DTA. As described in the description of the embodiment in which the system lead-in area SYLDI and the burst cutting area BCA are separately arranged, the burst cutting area BCA and the embossed pit area 211 are formed in the burst cutting area BCA due to unnecessary interference. It has already been explained that the noise component from the generated data to the reproduction signal increases. If the groove area 214 or the land area and the groove area 213 are not formed as the embossed pit area 211 as an embodiment of the fine uneven shape in the burst cutting area BCA, the data from the data formed in the burst cutting area BCA due to unnecessary interference is used. There is an effect that the noise component to the reproduction signal is reduced and the quality of the reproduction signal is improved. Matching the track pitch of the groove area 214 or land area and groove area 213 formed in the burst cutting area BCA with the track pitch of the system lead-in area SYLDI has the effect of improving the productivity of the information storage medium. That is, at the time of manufacturing the master disk of the information storage medium, the emboss pits in the system lead-in area are created with the feed motor speed of the exposure unit of the master disk recording device being constant. At this time, the burst cutting area BCA and the system lead-in area are formed by matching the track pitch of the groove area 214 or land area and groove area 213 formed in the burst cutting area BCA with the track pitch of the embossed pits in the system lead-in area SYLDI. Since the feed motor speed can be kept constant with SYLDI, there is no need to change the speed of the feed motor in the middle, so that pitch unevenness hardly occurs and the productivity of the information storage medium is improved.

  Table 5 shows each parameter value of the present embodiment in the read-only information storage medium, Table 6 shows each parameter value of the present embodiment in the write-once information storage medium, and Table 7 shows that of the present embodiment in the rewritable information storage medium. Each parameter value is shown.

  As can be seen by comparing Table 5 or Table 6 with Table 7 (particularly comparing the part (B)), the track-pitch and line of the rewritable-only information storage medium are higher than those of the read-only or recordable information storage medium. The recording capacity is increased by reducing the density (data bit length). As will be described later, the rewritable information storage medium employs land groove recording to reduce the influence of crosstalk between adjacent tracks and reduce the track pitch. Alternatively, the data lead length / track pitch (corresponding to the recording density) of the system lead-in / out area SYLDI / SYLDO can be set to the data lead-in / out in any of the read-only information storage medium, write-once information storage medium, and rewritable information storage medium. It is characterized in that it is larger than the data lead-out area DTLDI / DTLDO (lower recording density). The compatibility with the current DVD is ensured by bringing the data bit length and track pitch of the system lead-in / system lead-out area SYLDI / SYLDO close to the values of the lead-in area of the current DVD. In the present embodiment, as in the current DVD-R, the embossed steps in the system lead-in / system lead-out areas SYLDI / SYLDO of the write-once information storage medium are set shallow. As a result, the depth of the pre-groove of the write-once information storage medium can be reduced, and the reproduction signal modulation degree from the recording mark formed by write-once on the pre-groove can be increased. On the contrary, as a reaction, there arises a problem that the degree of modulation of the reproduction signal from the system lead-in / system lead-out area SYLDI / SYLDO becomes small. On the other hand, by making the data bit length (and track pitch) of the system lead-in / system lead-out area SYLDI / SYLDO coarse, the repetition frequency of the pits and spaces at the most packed position is set to the MTF ( By separating from the optical cutoff frequency of (Modulation Transfer Function) (substantially making it smaller), it is possible to increase the reproduction signal amplitude from the system lead-in / system lead-out area SYLDI / SYLDO and to stabilize the reproduction.

  FIG. 23 shows a detailed data structure comparison in the system lead-in SYLDI and the data lead-in DTLDI in various information storage media. FIG. 23A shows the data structure of the read-only information storage medium, FIG. 23B shows the data structure of the rewritable information storage medium, and FIG. 23C shows the data structure of the write-once information storage medium.

  As shown in FIG. 23 (a), the embossed pits are all formed in the system lead-in area SYLDI, data lead-in area DTLDI, and data area DTA in the read-only information storage medium except that only the connection zone CNZ has a mirror surface 210 The embossed pit area 211 is provided. The system lead-in area SYLDI is an embossed pit area 211, and the part where the connection zone CNZ is a mirror surface 210 is common. However, as shown in FIG. A land area and a groove area 213 are formed in the lead-in area DTLDI and the data area DTA, and a groove area 214 is formed in the data lead-in area DTLDI and the data area DTA in the write-once information storage medium. Information is recorded by forming recording marks in the land area and groove area 213 or groove area 214.

  The initial zone INZ indicates the start position of the system lead-in SYLDI. As information having a meaning recorded in the initial zone INZ, data ID (Identification Data) information including information on the physical sector number or the logical sector number described above is discretely arranged. As will be described later, data frame structure information composed of data ID, IED (ID Error Detection code), main data for recording user information, and EDC (Error Detection Code) is recorded in one physical sector. However, the data frame structure information is also recorded in the initial zone INZ. However, in the initial zone INZ, all pieces of main data information for recording user information are set to “00h”. Therefore, the only meaningful information in the initial zone INZ is the data ID information described above. The current position can be known from the physical sector number or logical sector number information recorded therein. That is, when information reproduction from the information storage medium is started by the information recording / reproducing unit 141 in FIG. 9, when reproduction is started from information in the initial zone INZ, first, the physical sector number recorded in the data ID information is started. Alternatively, the information of the logical sector number is extracted to move to the control data zone CDZ while confirming the current position in the information storage medium.

  The buffer zone 1 BFZ1 and the buffer zone 2 BFZ2 are each composed of 32 ECC blocks. As shown in Tables 5 to 7, each ECC block is composed of 32 physical sectors, so 32 ECC blocks correspond to 1024 physical sectors. In the buffer zone 1 BFZ1 and the buffer zone 2 BFZ2, as in the initial zone INZ, all the main data information is set to “00h”.

  The connection zone CNZ existing in the connection area CNA is an area for physically separating the system lead-in area SYLDI and the data lead-in area DTLDI. (Mirror surface).

The reference code zone RCZ of the read-only information storage medium and the write-once information storage medium is used for adjusting the playback circuit of the playback apparatus (for example, during adaptive equalization performed in the tap controller 332 of FIG. 13). In the area used for automatic adjustment of each tap coefficient value, the data frame structure information described above is recorded. The length of the reference code is 1 ECC block (= 32 sectors). The present embodiment is characterized in that a reference code zone RCZ of the read-only information storage medium and the write-once information storage medium is arranged next to the data area DTA. In both the current DVD-ROM disc and the current DVD-R disc, a control data zone is arranged between a reference code recording zone (Reference code zone) and a data area (Data Area). There is a gap between the data area. If the reference code recording zone and the data area are separated from each other, the tilt amount and light reflectance of the information storage medium or the recording sensitivity of the recording film (in the case of a write-once information storage medium) slightly changes. Even if the circuit constants of the reproducing apparatus are adjusted at the recording zone, there arises a problem that the optimum circuit constants in the data area are shifted. In order to solve the above problem, when a reference code recording zone RCZ is arranged adjacent to a data area DTA, the circuit constants of the information reproducing apparatus are set in the reference code recording zone RCZ. When optimized, the optimized state is maintained with the same circuit constant in the adjacent data area DTA. Data area (Data Area) If you want to reproduce the signal accurately in any place in the DTA,
(1) Optimize circuit constant of information reproducing device in reference code zone RCZ → (2) Information reproducing device while reproducing the portion closest to reference code recording zone RCZ in data area DTA The circuit constant is optimized again. (3) The circuit constant is optimized again while reproducing information at the intermediate position between the target position in the data area DTA and the position optimized in (2). The signal reproduction at the target position can be performed with very high accuracy by moving to the position and performing the signal reproduction step.

  Guard track zones 1 and 2 (Guard track zones) GTZ1 and GTZ2 existing in the recordable information storage medium and the rewritable information storage medium are the start boundary position of the data lead-in area DTLDI, the disk test zone DKTZ, and the drive test zone DRTZ. This is an area for defining the boundary position, and this area is defined as an area that cannot be recorded by forming a recording mark. Since the guard track zone 1 GTZ1 and the guard track zone 2 GTZ2 exist in the data lead-in area DTLDI, a pre-groove area in the write-once information storage medium, or a groove area and a land area in the rewritable information storage medium. Is pre-formed. Since the wobble address is recorded in advance in the pre-groove area or the groove area and land area as shown in Tables 5 to 7, the current position in the information storage medium is determined using this wobble address.

  The disk test zone DKTZ is an area provided for the manufacturer of the information storage medium to perform a quality test (evaluation).

  The drive test zone DRTZ is secured as an area for trial writing before the information recording / reproducing apparatus records information on the information storage medium. The information recording / reproducing apparatus can perform trial writing in this area in advance, determine the optimum recording condition (write strategy), and then record information in the data area DTA under the optimum recording condition.

  Information in the disc identification zone DIZ in the rewritable information storage medium (FIG. 23 (b)) can be recorded independently in the optional information recording area by the manufacturer / name information of the recording / reproducing apparatus, additional information related thereto, and the manufacturer. This is an area that can be additionally written for each set of drive descriptors (Drive description) composed of various areas.

  Defect management area 1 DMA1 and defect management area 2 DMA2 in the rewritable information storage medium (FIG. 23B) are locations where defect management information is recorded in the data area DTA. For example, when a defect location occurs The replacement part information etc. are recorded.

  In the recordable information storage medium (FIG. 23C), there are an RMD duplication zone RDZ, a recording position management zone RMZ, and an R physical information zone R-PFIZ. In the recording position management zone RMZ, recording position management data RMD (Recording Management Data), which is management information relating to the recording position of data updated by the data addition process, is recorded (details will be described later). As will be described later with reference to FIG. 24, in this embodiment, a recording position management zone RMZ is set for each border area BRDA, and the area of the recording position management zone RMZ can be expanded. As a result, even if the required recording position management data RMD area increases due to an increase in the frequency of additional recording, it can be handled by expanding the sequential recording position management zone RMZ, so that the number of additional recordings can be greatly increased. to be born. In this case, in the present embodiment, the recording position management zone RMZ is arranged in the border-in BRDI corresponding to each in-border area BRDA (arranged immediately before each in-border area BRDA). In the present embodiment, the border-in BRDI and the data lead-in area DTLDI corresponding to the first in-border area BRDA # 1 are combined, and the formation of the first border-in BRDI in the data area DTA is omitted and the data area DTA is valid. We are making use of it. That is, the recording position management zone RMZ in the data lead-in area DTLDI shown in FIG. 23C is used as a recording location of the recording position management data RMD corresponding to the first bordered area BRDA # 1.

  The RMD duplication zone RDZ is a place where the information of the recording position management data RMD satisfying the following conditions in the recording position management zone RMZ is recorded, and has the recording position management data RMD as in the present embodiment. The reliability of the recording position management data RMD is increased. That is, when the recording position management data RMD in the recording position management zone RMZ becomes impossible due to the influence of dust or scratches on the surface of the write-once information storage medium, the recording position recorded in this RMD deduplication zone RDZ The management data RMD is reproduced, and the remaining necessary information is collected by tracing, whereby the latest information on the recording position management data RMD can be restored.

  In the RMD duplication zone RDZ, recording position management data RMD at the time of closing the border (s) is recorded. As will be described later, one border is closed, and a new recording position management zone RMZ is defined every time a next new border area is set, so every time a new recording position management zone RMZ is created, It may be said that the last recording position management data RMD related to the previous border area is recorded in this RMD duplication zone RDZ. When the same information is recorded in the RMD deduplication zone RDZ every time the recording position management data RMD is additionally recorded on the write-once information storage medium, the RMD duplication zone RDZ is filled with a relatively small number of additional writes, so the number of additional writes The upper limit of becomes smaller. In contrast, when the border is closed as in the present embodiment or when the recording position management zone in the border-in BRDI is full, a new recording position management zone RMZ is formed using the R zone. When creating a management zone, only the last recording position management data RMD in the previous recording position management zone RMZ can be recorded in the RMD duplication zone RDZ, allowing additional recording using the RMD duplication zone RDZ. There is an effect that the number of times can be improved.

  For example, the recording position management data RMD in the recording position management zone RMZ corresponding to the border area BRDA in the middle of additional recording (before closing) cannot be reproduced due to the influence of dust or scratches on the surface of the additional information storage medium. In this case, the location of the border area BRDA that has already been closed can be known by reading the last recorded recording position management data RMD in the RMD duplication zone RDZ. Therefore, by tracing the other locations in the data area DTA of the information storage medium, the location of the in-border area BRDA (before closing) and the information content recorded there can be collected, and the latest recording The information of the location management data RMD can be restored.

  Information similar to the physical format information PFI (which will be described in detail later) in the control data zone CDZ that exists in common in FIGS. 23A to 23C is recorded in the R physical information zone R-PFIZ. .

  FIG. 24 shows the data structure in the RMD duplication zone RDZ and the recording position management zone RMZ in the write-once information storage medium (FIG. 23 (c)). FIG. 24A shows the same thing as FIG. 23C, and an enlarged view of the RMD duplication zone RDZ and the recording position management zone RMZ in FIG. 23C is shown in FIG. As described above, in the recording position management zone RMZ in the data lead-in area DTLDI, data related to recording position management corresponding to the first bordered area BRDA is collected in one recording management data (Recording Management Data) RMD. Each time the content of the recording position management data RMD generated when the additional recording process is performed on the write-once information storage medium is updated, new recording position management data RMD is sequentially added to the rear side. That is, recording management data RMD is recorded in units of size of one physical segment block (the physical segment block will be described later), and new recording position management data RMD is updated each time the data content is updated. Will be added to the back sequentially. In the example of FIG. 24B, since the management data has changed where the recording position management data RMD # 1 and # 2 have been recorded in advance, the data after the change (after update) is used as the recording position management data RMD. An example of recording immediately after the recording position management data RMD # 2 is shown as # 3. Therefore, a reserved area 273 exists in the recording position management zone RMZ so that additional recording is possible.

  FIG. 24B shows the structure in the recording position management zone RMZ existing in the data lead-in area DTLDI. However, the structure is not limited to this, and the recording position management zone in the border-in BRDI or the border-in area BRDA described later. The structure in the RMZ (or extended recording position management zone: called extended RMZ) is also the same as the structure shown in FIG.

In the present embodiment, when the first bordered area BRDA # 1 is closed or the data area DTA is finished (finalized), the reserved area 273 shown in FIG. Process to fill all. This
(1) The reserved area 273 in the “unrecorded state” disappears, and the stabilization of tracking correction by the DPD (Differential Phase Detection) detection method is guaranteed. (2) The last recording position management data RMD is multiplexed in the former reserved area 273. As a result, the reliability at the time of reproduction of the last recording position management data RMD is greatly improved. There is an effect that can be done.

  The processing method is not limited to the recording position management zone RMZ in the data lead-in area DTLDI, but in this embodiment, the recording position management zone RMZ (or the extended recording position management zone in the border-in BRDI or the border-in area BRDA described later). : In the case where the corresponding border area BRDA is closed or the data area DTA is terminated (finalized), the process of filling all the reserved areas 273 with the last recording position management data RMD is performed. Do.

  The RMD duplication zone RDZ is divided into an RDZ lead-in RDZLI and a recording area 271 of the corresponding RMZ last recording position management data RMD. As shown in FIG. 24B, the RDZ lead-in RDZLI includes a system reserved area SRSF with a data size of 48 KB and a unique ID area UIDF with a data size of 16 KB. All the system reserved areas SRSF are set to “00h”.

  The present embodiment is characterized in that the RDZ lead-in RDZLI is recorded in the additionally recordable data lead-in area DTLDI. In the recordable information storage medium of this embodiment, the RDZ lead-in RDZLI is shipped in an unrecorded state immediately after manufacture. The RDZ lead-in RDZLI information is recorded for the first time at the stage of using this recordable information storage medium in the user-side information recording / reproducing apparatus. Therefore, by determining whether or not information is recorded in the RDZ lead-in RDZLI immediately after mounting the recordable information storage medium in the information recording / reproducing apparatus, the target recordable information storage medium is in a state immediately after manufacture and shipment. Or at least once used. Further, as shown in FIG. 24, the RMD duplication zone RDZ is arranged on the inner peripheral side from the recording position management zone RMZ corresponding to the first bordered area BRDA, and the RDZ lead-in RDZLI is arranged in the RMD duplication zone RDZ. There are the following features of this embodiment.

  Information (RDZ lead-in RDZLI) indicating whether the write-once information storage medium is in a state immediately after manufacture / shipment or at least once used (RDZ lead-in RDZLI) is used in a common use purpose (improving the reliability of RMD). Placement improves the efficiency of collecting information. Further, by arranging the RDZ lead-in RDZLI on the inner circumference side from the recording position management zone RMZ, it is possible to shorten the time required for collecting necessary information. When the information recording medium is mounted on the information recording / reproducing apparatus, the information recording / reproducing apparatus starts reproduction from the burst cutting area BCA arranged on the innermost side as shown in FIG. 22, and sequentially moves the reproduction position outward. The playback location is changed to the system lead-in area SYLSI and the data lead-in area DTLDI. It is determined whether information is recorded in the RDZ lead-in RDZLI in the RMD duplication zone RDZ. In a recordable information storage medium that has not been recorded even immediately after shipment, no recording position management data RMD is recorded in the recording position management zone RMZ, so that no information is recorded in the RDZ lead-in RDZLI. Can be determined as “not used immediately after shipment”, the reproduction of the recording position management zone RMZ can be omitted, and the time required for collecting necessary information can be shortened.

  In the unique ID area UIDF, as shown in FIG. 24C, information relating to an information recording / reproducing apparatus that uses a recordable information storage medium immediately after shipment for the first time (recording is started) is recorded. That is, the drive manufacturer ID 281 of the information recording / reproducing apparatus, the serial number 283, and the model number 284 of the information recording / reproducing apparatus are recorded. In the unique ID area UIDF, the same information of 2 KB (strictly, 2048 bytes) shown in FIG. 24C is repeatedly recorded eight times. The information in the unique disk ID 287 includes year information 293, month information 294, day information 295, time information 296, minute information 297, and second information 298 when used (start recording) for the first time as shown in FIG. To be recorded. The data type of each information is described in HEX, BIN, and ASCII as described in FIG. 24D, and the number of used bytes is 2 bytes or 4 bytes.

  The feature of this embodiment is that the size of the area of the RDZ lead-in RDZLI and the size of the one recording management data RMD are an integral multiple of 64 KB, that is, the user data size in one ECC block. is there. In the case of a write-once information storage medium, it is impossible to rewrite the data of the changed ECC block to the information storage medium after changing a part of the data in one ECC block. Therefore, especially in the case of a write-once information storage medium, as will be described later, recording is performed in units of recording clusters constituted by an integral multiple of a data segment including one ECC block. Therefore, if the size of the RDZ lead-in area RDZLI and the size of the one recording position management data RMD are different from the user data size in the ECC block, a padding area or a stuffing area for adjusting to the recording cluster unit is required. Substantial recording efficiency decreases. By setting the size of the RDZ lead-in RDZLI area and the size of the one recording position management data RMD to an integral multiple of 64 KB as in the present embodiment, it is possible to prevent a decrease in recording efficiency.

  The corresponding RMZ last recording position management data RMD recording area 271 in FIG. 24B will be described. As described in Japanese Patent No. 2621459, there is a method of recording intermediate information at the time of recording interruption inside the lead-in area. In this case, it is necessary to sequentially add intermediate information (recording position management data RMD in this embodiment) to this area every time recording is interrupted or every time additional recording processing is performed. For this reason, if the recording interruption or additional recording process is frequently repeated, this area becomes full immediately and further additional processing becomes impossible. In order to solve this problem, in this embodiment, the RMD duplication zone RDZ is set as an area in which the recording position management data RMD updated only when a specific condition is satisfied, and thinned out under the specific condition. Recording position management data RMD is recorded. In this way, by reducing the frequency of the recording position management data RMD that is additionally recorded in the RMD duplication zone RDZ, it is possible to prevent the RMD duplication zone RDZ from becoming full, and to increase the number of times that can be additionally recorded on the recordable information storage medium. There is an effect that it can be greatly improved. In parallel with this, the recording position management data RMD updated for each additional recording process is within the border-in BRDI shown in FIG. 27 (c) (as shown in FIG. Data is sequentially added to a recording position management zone RMZ in the data lead-in area DTLDI) or a recording position management zone RMZ using an R zone described later. Then, when creating a new recording position management zone RMZ such as creating the next border area BRDA (setting a new border-in BRDI) or setting a new recording position management zone RMZ in the R zone, The latest recording position management data RMD in a state immediately before creating a new recording position management zone RMZ is recorded in the RMD duplication zone RDZ (corresponding RMZ last recording position management data RMD recording area 271). This not only greatly increases the number of times that data can be written to the write-once information storage medium, but also produces the effect that the latest RMD position search is facilitated by using this area.

  FIG. 26 shows a data structure in the recording position management data RMD shown in FIG. 26 (a) to 26 (c) have the same contents as FIGS. 24 (a) to 24 (b). As described above, in this embodiment, the border-in BRDI for the first bordered area BRDA # 1 is also used as a part of the data lead-in area DTLDI. Recording position management data RMD # 1 to # 3 corresponding to the bordered area are recorded. If no data is recorded in the data area DTA, the recording position management zone RMZ becomes a reserved area 273 in which no data is recorded. The recording position management data RMD updated each time data is added to the data area DTA is recorded at the first location in the reserved area 273, and the recording corresponding to the first border area in the recording position management zone RMZ. The location management data RMD is sequentially added. The size of the recording position management data RMD added to the recording position management zone RMZ every time is 64 Kbytes. In this embodiment, since one ECC block is composed of 64 KB data, the additional recording process is simplified by matching the data size of the recording position management data RMD to the 1 ECC block size. As will be described later, in this embodiment, one guard segment is added before and after one ECC block data 412 to form one data segment 490, and one or more (n) data segments are extended guard field 258. 259 are added to form recording clusters 540 and 542 in units of additional writing or rewriting. When recording position management data RMD is recorded, recording clusters 540 and 542 including only one data segment (one ECC block) are sequentially added in the recording position management zone RMZ. As will be described later, the length of a place where one data segment 531 is recorded is equal to the length of one physical segment block composed of seven physical segments 550 to 556.

The data structure in one piece of recording position management data RMD # 1 is shown in FIG. FIG. 26C shows the data structure in the recording position management data RMD # 1 in the data lead-in area DTLDI. However, the present invention is not limited to this, and the recording position management data RMD # recorded in the RMD duplication zone RDZ. Data structure in A, #B (FIG. 24), (extended) recording position management data RMD recorded in the border-in BRDI described later, and (extended) recording position management data RMD recorded in the R zone, and the border The RMD copy CRMD (FIG. 27D) recorded in the out BRDO has the same structure. As shown in FIG. 26 (c), one recording management data RMD is composed of a reserved area and RMD fields from "0" to "21". In this embodiment, 32 physical sectors are included in one ECC block composed of 64 KB user data, and 2 KB (strictly 2048 bytes) of user data is contained in one physical sector. Each is recorded. Each RMD field is allocated for each 2048 bytes according to the user data size recorded in one physical sector, and a relative physical sector number is set. RMD fields are recorded on the recordable information storage medium in the order of the relative physical sector numbers. The outline of the data contents recorded in each RMD field is as follows: • RMD field 0: information on the disk status and data area allocation (information on the location of various data in the data area)
-RMD field 1 ... Information on the used test zone and information on the recommended recording waveform-RMD field 2-Area that can be used by the user-RMD field 3 ... Information on the start position information of the border area and the extended RMZ position-RMD field 4- 21: Information on the position of the R zone.

As shown in FIG. 23, the system lead-in area is arranged on the opposite side of the data area across the data lead-in area in any of the read-only, write-once, and rewritable information storage media. Further, as shown in FIG. The present embodiment is characterized in that the burst cutting area BCA and the data lead-in area DTLDI are arranged on opposite sides of the system lead-in area SYLDI. When the information storage medium is inserted into the information reproducing apparatus or information recording / reproducing apparatus shown in FIG. 9, the information reproducing apparatus or information recording / reproducing apparatus (1) reproduces information in the burst cutting area BCA → (2) system lead-in area Reproduction of information in the information data zone CDZ in SYLDI → (3) Reproduction of information in the data lead-in area DTLDI (in the case of write-once type or rewritable type)
→ (4) Readjustment of playback circuit constants in the reference code recording zone RCZ (optimization)
(5) Processing is performed in the order of reproduction of information recorded in the data area DTA or recording of new information.

  As shown in FIG. 23, since information is arranged in order from the inner periphery side in the order of the above processing, unnecessary access processing to the inner periphery becomes unnecessary, and the number of accesses can be reduced to reach the data area DTA. There is an effect of shortening the start time of reproducing information recorded in the data area DTA or recording new information. In addition, since the slice level detection method is used for signal reproduction in the system lead-in area SYLDI and PRML is used for signal reproduction in the data lead-in area DTLDI and the data area DTA, the data lead-in area DTLDI and the data area DTA are adjacent to each other. When the reproduction is performed in order from the inner circumference side, it is possible to reproduce signals stably and continuously by switching from the slice level detection circuit to the PRML detection circuit only once between the system lead-in area SYLDI and the data lead-in area DTLDI. Become. For this reason, since the number of times of switching the reproduction circuit in accordance with the reproduction procedure is small, the process control is simplified and the reproduction start time in the data area is shortened.

  FIG. 25 shows a comparison of data structures in the data area DTA and the data lead-out area DTLDO in various information storage media. 25A shows the data structure of the read-only information storage medium, FIGS. 25B and 25C show the data structure of the rewritable information storage medium, and FIGS. 25D to 25F show the write-once information. The data structure of the storage medium is shown. In particular, FIGS. 25 (b) and (d) show the structure at the initial stage (before recording), and FIGS. 25 (c), (e) and (f) show the state in which the recording (additional writing or rewriting) has advanced to some extent. The data structure is shown.

  As shown in FIG. 25A, the data recorded in the data lead-out area DTLDO and the system lead-out area SYLDO in the read-only information storage medium is the same as the buffer zone 1 BFZ1 and the buffer zone 2 BFZ2 in FIG. It has a data frame structure (the data frame structure will be described later), and all main data values in the data frame structure are set to “00h”. The read-only information storage medium can be used as the user data pre-recording area 201 over the entire area in the data area DTA. However, as will be described later, in both the write-once information storage medium and the rewritable information storage medium, the user Data rewrite / appendable range 202 to 205 is narrower than data area DTA.

  In the recordable information storage medium or the rewritable information storage medium, a spare area SPA is provided at the innermost periphery of the data area DTA. When a defect location occurs in the data area DTA, a replacement process is performed using the replacement area SPA. In the case of a rewritable information storage medium, the replacement history information (defect management information) is shown in FIG. Data are recorded in the management area 1 DMA1, the defect management area 2 DMA2, and the defect management area 3 DMA3 and the defect management area 4 DMA4 shown in FIGS. The defect management information recorded in the defect management area 3 DMA3 and the defect management area 4 DMA4 in FIGS. 25B and 25C is recorded in the defect management area 1 DMA1 and the defect management area 2 DMA2 in FIG. The same content as the information is recorded. In the case of a write-once information storage medium, replacement history information (defect management information) when replacement processing is performed is a recording position that exists in the data lead-in area DTLDI shown in FIG. Recorded in the copy information C_RMZ of the contents recorded in the management zone. Although the current DVD-R disc did not perform defect management, as the number of DVD-R discs manufactured increased, DVD-R discs having a part of the defect became available, and a write-once information storage medium There is a growing demand for improved reliability of information recorded in In the embodiment shown in FIG. 25, a replacement area SPA is set for the write-once information storage medium to enable defect management by replacement processing. As a result, it is possible to improve the reliability of recorded information by performing defect management processing even on a write-once information storage medium having a defect location in part. When the rewritable information storage medium or write-once information storage medium has many defects, the information recording / reproducing apparatus judges on the user side and the state immediately after the sale to the user shown in FIGS. Thus, the extended spare areas ESPA, ESPA1 and ESPA2 are automatically set so that the alternative place can be expanded. By making it possible to set the extended substitution areas ESPA, ESPA1, and ESPA2 in this way, it is possible to sell media with many defects for manufacturing reasons. It becomes. As shown in FIGS. 25 (c), 25 (e), and 25 (f), when the extended substitution areas ESPA, ESPA1, and ESPA2 are added in the data area DTA, the user data rewrite or additionally recordable ranges 203 and 205 are reduced. It is necessary to manage the position information. In the rewritable information storage medium, the information is recorded in the defect management area 1 DMA1 to the defect management area 4 DMA4 in the control data zone CDZ as described later. In the case of a recordable information storage medium, recording is performed in a recording position management zone RMZ existing in the data lead-in area DTLDI and the border-out BRDO as will be described later. As will be described later, it is recorded in recording management data (Recording Management Data) RMD in the recording management zone RMZ. Since the recording position management data RMD is additionally recorded in the recording position management zone RMZ every time the management data contents are updated, the extended replacement area can be set again and again (first in the embodiment of FIG. 25 (e)). Since the extended replacement area 1 EAPA1 is set in the area and there are many defects even after all of the extended replacement area 1 EAPA1 has been used up, further replacement area setting is necessary. It is possible to update and manage in a timely manner.

  The guard track zone 3 GTZ3 shown in FIGS. 25B and 25C is arranged for separation between the defect management area 4 DMA4 and the drive test zone DRTZ. The guard track zone 4 GTZ4 is servo-calibrated with the disk test zone DKTZ. It is arranged for separation from the area (Servo Calibration Zone) SCZ. The guard track zone 3 GTZ3 and the guard track zone 4 GTZ4 are defined as areas that should not be recorded by forming a recording mark, like the guard track zone 1 GTZ1 and the guard track zone 2 GTZ2 shown in FIG. . Since the guard track zone 3 GTZ3 and the guard track zone 4 GTZ4 exist in the data lead-out area DTLDO, a pre-groove area in the write-once information storage medium, or a groove area and a land area in the rewritable information storage medium. Is pre-formed. Since the wobble address is recorded in advance in the pre-groove area or the groove area and land area as shown in Tables 5 to 7, the current position in the information storage medium is determined using this wobble address.

  Similarly to FIG. 23, the drive test zone DRTZ is reserved as an area for trial writing before the information recording / reproducing apparatus records information on the information storage medium. The information recording / reproducing apparatus can perform trial writing in this area in advance, determine the optimum recording condition (write strategy), and then record information in the data area DTA under the optimum recording condition.

  As in FIG. 23, the disk test zone DKTZ is an area provided for the manufacturer of the information storage medium to perform a quality test (evaluation).

  The pre-groove area in the write-once information storage medium or the groove area and land area in the rewritable information storage medium are formed in advance in all areas in the data lead-out area DTLDO other than the servo calibration zone SCZ. Recording of record marks (additional writing or rewriting) is possible. As shown in FIGS. 25C and 25E, the servo calibration zone SCZ is similar to the system lead-in area SYLDI in place of the pre-groove area 214 or land area and groove area 213. An emboss pit area 211 is formed. This area forms a continuous track with embossed pits following the other areas of the data lead-out area DTLDO, and this track is continuously connected in a spiral shape and is embossed pits over 360 degrees along the circumference of the information storage medium. Is forming. This area is provided for detecting the tilt amount of the information storage medium using the DPD (Deferencial Phase Detect) method. When the information storage medium is tilted, an offset occurs in the amplitude of the track deviation detection signal using the DPD method, and the tilt amount can be detected with the offset amount and the tilt direction can be accurately detected with the offset direction. By utilizing this principle, embossed pits capable of DPD detection are formed in advance in the outermost peripheral portion of the information storage medium (the outer peripheral portion in the data lead-out area DTLDO). Therefore, it is possible to detect the inclination with high accuracy at a low cost without adding a special component (for detecting the inclination) to the optical head. Further, by detecting the inclination amount of the outer peripheral portion, the servo can be stabilized even in the data area DTA (by correcting the inclination amount). In the present embodiment, the track pitch in the servo calibration area SCZ is matched with other areas in the data lead-out area DTLDO to improve the manufacturability of the information storage medium and to reduce the medium price by improving the yield. . That is, in the write-once information storage medium, pregrooves are formed in other areas in the data lead-out area DTLDO. To create a pre-groove. At this time, by adjusting the track pitch in the servo calibration area SCZ to other areas in the data lead-out area DTLDO, the feed motor speed can be kept constant in the servo calibration area SCZ, so that pitch unevenness hardly occurs. Manufacturability of the information storage medium is improved.

  As another embodiment, there is a method of matching at least one of the track pitch and the data bit length in the servo calibration area SCZ with the track pitch or the data bit length of the system lead-in area SYLDI. As described above, the DPD method is used to measure the tilt amount and the tilt direction in the servo calibration area SCZ, and use the result in the data area DTA to stabilize the servo in the data area DTA. As a method for predicting the amount of inclination in the data area DTA, the amount of inclination in the system lead-in area SYLDI and its direction are measured in advance by the DPD method, and the relationship with the measurement result in the servo calibration area SCZ is used. Can be predicted. When the DPD method is used, there is a feature that the offset amount of the detection signal amplitude with respect to the inclination of the information storage medium and the direction in which the offset is generated vary depending on the track pitch of the emboss pit and the data bit length. Therefore, by detecting at least one of the track pitch and the data bit length in the servo calibration area SCZ to the track pitch or the data bit length in the system lead-in area SYLDI, the detection characteristic regarding the offset amount of the detection signal and the direction in which the offset is generated. Are matched in the servo calibration area SCZ and the system lead-in area SYLDI, and the correlation between the two can be easily obtained, so that the inclination amount and direction in the data area DTA can be easily predicted.

As shown in FIGS. 23 (c) and 25 (d), the write-once information storage medium has drive test zones DRTZ at two locations on the inner peripheral side and the outer peripheral side. As the number of trial writings performed in the drive test zone DRTZ is increased, the optimum recording conditions can be searched in detail by changing the parameters finely, and the recording accuracy in the data area DTA is improved. In the rewritable information storage medium, it is possible to reuse the drive test zone DRTZ by overwriting, but in the write-once information storage medium, if the number of trial writings is increased to increase the recording accuracy, the drive test zone DRTZ can be reused. There is a problem that it will be used up quickly. In order to solve this problem, the present embodiment is characterized in that the extended drive test zone (Extended Drive Test Zone) EDRTZ can be set sequentially from the outer peripheral portion along the inner peripheral direction, and the drive test zone can be expanded. There is. In this embodiment, the extended drive test zone setting method and the test writing method in the set extended drive test zone are as follows. The extended drive test zone EDRTZ is set (framed) sequentially from the outer peripheral direction (the one closer to the data lead-out area DTLDO) toward the inner peripheral side. As shown in FIG. The extended drive test zone 1 EDRTZ1 is set as an area gathered from the place closest to the outer circumference (the place closest to the data lead-out area DTLDO), and after the extended drive test zone 1 EDRTZ1 is used up, the inner circumference side is reached. Next, the extended drive test zone 2 EDRTZ2 can be set as an existing area.

2. In the extended drive test zone EDRTZ, trial writing is performed sequentially from the inner circumference side. When trial writing is performed in the extended drive test zone EDRTZ, the groove area is arranged in a spiral shape from the inner circumference side to the outer circumference side. The test writing of this time is performed in an unrecorded place immediately behind the place where the test writing was performed (already recorded).

  The data area has a structure that is additionally written along the groove area 214 arranged in a spiral shape from the inner circumference side to the outer circumference side, and the trial writing in the extended drive test zone is performed immediately before. By using the method of appending sequentially after the writing location, the processing of “Confirmation of the trial writing location performed immediately before” → “Execution of the current trial writing” can be performed serially, so the trial writing processing becomes easy. In addition, it is easy to manage locations that have already been test-written in the extended drive test zone EDRTZ.

3. The data lead-out area DTLDO can be reset in the form including the extended drive test zone EDRTZ .... In FIG. 25 (e), two expansion replacement areas 1 ESPA1 and 2 ESPA2 are set in the data area DTA. An example in which extended drive test zone 1 EDRTZ1 and extended drive test zone 2 EDRTZ2 are set is shown. In this case, the present embodiment is characterized in that the area including the extended drive test zone 2 EDRTZ2 can be reset as the data lead-out area DTLO as shown in FIG. In conjunction with this, the range of the data area DTA is reset in a form that narrows the range, and management of the additionally recordable range 205 of user data existing in the data area DTA becomes easy. When resetting as shown in FIG. 25 (f), the setting place of the extended replacement area 1 ESPA1 shown in FIG. 25 (e) is regarded as “an already used extended replacement area”, and the expansion in the extended drive test zone EDRTZ is performed. Substitution area 2 It is managed that there is an unrecorded area (area in which additional writing can be written) only in ESPA2. In this case, the non-defect information recorded in the extended replacement area 1 ESPA1 and used for replacement is moved to the place of the non-replacement area in the extended replacement area 2 ESPA2 and the defect management information is rewritten. The start position information of the data lead-out area DTLDO reset at this time is recorded in the arrangement position information of the latest (updated) data area DTA in the RMD field 0 in the recording position management data RMD as shown in Table 11. Is done.

  The structure of the border area in the write-once information storage medium will be described with reference to FIG. When one border area is set for the write-once information storage medium for the first time, as shown in FIG. 28A, the bordered area BRDA # on the inner circumference side (side closest to the data lead-in area DTLDI) After 1 is set, a border out BRDO is formed behind it.

  Further, when it is desired to set the next Bordered Area BRDA # 2, as shown in FIG. 28B, the next (# 1) is placed behind the previous (# 1) border-out BRDO. ) After the border-in BRDI is formed, the next in-border area BRDA # 2 is set, and when the next in-border area BRDA # 2 is to be closed, the border-out BRDO of (# 2) is set immediately thereafter. Form. In the present embodiment, a state in which the next (# 1) Border in BRDI is formed after the previous (# 1) border out BRDO is called a border zone (BRDZ). It is out. The border zone BRDZ is set to prevent the optical head from overrunning between the border areas BRDA when the information is reproduced by the information reproducing apparatus (assuming the DPD detection method). Therefore, when the recordable information storage medium on which the information is recorded is reproduced by the reproduction-only device, the border-out BRDO and the border-in BRDI are already recorded, and the border-out BRDO is placed behind the last bordered area BRDA. It is assumed that the border closing process to be recorded is performed. The first border area BRDA # 1 is composed of 4080 or more physical segment blocks, and the first border area BRDA # 1 in the radial direction on the write-once information storage medium needs to have a width of 1.0 mm or more. There is. FIG. 28B shows an example in which an extended drive test zone EDRTZ is set in the data area DTA.

  FIG. 28C shows a state after the write-once information storage medium is finalized. FIG. 28C shows an example in which the extended drive test zone EDRTZ is incorporated in the data lead-out area DTLDO and the extended replacement area ESPA is already set. In this case, it is filled with the last border-out BRDO so as not to leave the addable range 205 of user data.

A detailed data structure in the border zone BRDZ described above is shown in FIG. Each information is recorded in a size unit of one physical segment block (physical segment block) which will be described later. Copy information C_RMZ of the contents recorded in the recording position management zone is first recorded in the border-out BRDO, and a border end mark (Stop Block) STB indicating that the border-out BRDO is present is recorded. Further, when the next border-in BRDI comes, it indicates that the border area will come next to the “N1th” physical segment block counted from the physical segment block in which this stop block STB is recorded. The first mark (Next Border Marker) NBM, the second mark NBM indicating that the next border area will come to the “N2” physical segment block, and the border area next to the “N3” physical segment block Third marks NBM indicating that they are coming are discretely recorded at a total of three locations for each size of one physical segment block. In the next border-in BRDI, updated physical format information (Updated Physical Format Information) U_PFI is recorded. When the next border area does not come in the current DVD-R or DVD-RW disc (within the last border-out BRDO), the “marker NBM indicating the next border” shown in FIG. The place to be (place of one physical segment block size) is held as “a place where no data is recorded”. When the border is closed in this state, the recordable information storage medium (current DVD-R or DVD-RW disc) can be played back on a conventional DVD-ROM drive or a conventional DVD player. A conventional DVD-ROM drive or a conventional DVD player uses a DPD (Differential Phase Detect) method using a recording mark recorded on the write-once information storage medium (current DVD-R or DVD-RW disc). Detects the track deviation. However, since there is no recording mark for one physical segment block size in the above “place where no data is recorded”, DPD (Differential Phase
There is a problem that the track servo cannot be stably applied because the track deviation cannot be detected using the (Detect) method. In the present embodiment, as a countermeasure against the problems of the above-mentioned current DVD-R or DVD-RW disc, (1) When the next border area does not come, “in the place where the mark NBM indicating the next border is to be recorded” (2) When the next border area comes, the data of the specific pattern is recorded partially in the place of the “marker NBM indicating the next border”. A new method is adopted in which “overwrite processing” is performed discretely with a specific recording pattern and used as identification information indicating “the next border area is coming”.

By setting the mark indicating the next border by overwriting in this way, even if the next border area does not come as shown in (1), the “location where the mark NBM indicating the next border should be recorded” A recording mark having a specific pattern can be formed in advance, and the effect that the track servo can be stably applied even if the track deviation is detected by the DPD method with the reproduction-only information reproducing apparatus after the border is closed. When a new recording mark is overwritten on a portion of the recordable information storage medium where a recording mark has already been formed, the information recording / reproducing apparatus or the information reproducing apparatus uses the PLL circuit shown in FIG. There is a concern that the stabilization of In this embodiment as a countermeasure against the fear,
(3) a method of changing the overwriting status depending on the location in the same data segment when overwriting at the position of “next border indicating mark NBM” of one physical segment block size; and (4) partial in sync data 432 And overwriting on the sync code 431 is prohibited. (5) A method of overwriting in a place excluding the data ID and IED is newly adopted. As will be described in detail later, data fields 411 to 418 for recording user data and guard areas 441 to 448 are alternately recorded on the information storage medium. A combination of the data fields 411 to 418 and the guard areas 441 to 448 is called a data segment 490, and one data segment length is equal to one physical segment block length. The PLL circuit shown in FIG. 9 is particularly easy to pull in the PLL in the VFO regions 471 and 472. Therefore, if the PLL is removed immediately before the VFO areas 471 and 472, the PLL can be easily re-incorporated using the VFO areas 471 and 472, so that the information recording / reproducing apparatus or the entire system in the information reproducing apparatus can be used. The impact is reduced. Using this situation, as described above, (3) The overwriting situation is changed depending on the location in the data segment, and the overwriting amount of the specific pattern is increased in the rear portion close to the VFO areas 471 and 472 in the same data segment. Thus, it is possible to easily determine the “marker indicating the next border” and to prevent the deterioration of the accuracy of the signal PLL during reproduction. As will be described in detail with reference to FIGS. 58 and 38, in one physical sector, the sync code 433 (SY0 to SY3) is disposed and the sync data 434 disposed between the sync codes 433. It is composed of a combination of The information recording / reproducing apparatus or the information reproducing apparatus extracts the sync code 433 (SY0 to SY3) from the channel bit string recorded on the information storage medium, and detects the break of the channel bit string. As will be described later, the position information (physical sector number or logical sector number) of data recorded on the information storage medium is extracted from the data ID information. An error in the data ID is detected using the IED arranged immediately thereafter. Accordingly, in this embodiment, (5) overwriting on the data ID and the IED is prohibited, and (4) by partially overwriting the sync data 432 excluding the sync code 431, the “next border” Even within the mark NBM ”indicating“ ”, detection of the data ID position using the sync code 431 and reproduction (content interpretation) of the information recorded in the data ID are possible.

  FIG. 27 shows another embodiment different from FIG. 28 regarding the structure of the border area in the write-once information storage medium. FIGS. 27A and 27B show the same contents as FIGS. 28A and 28B. In FIG. 27, the state of the write-once information storage medium after finalization is different from FIG. For example, as shown in FIG. 27C, when it is desired to finalize the information after the information recording in the border area BRDA # 3 is finished, the border is immediately after the border area BRDA # 3 as the border close process. Out BRDO is formed. Thereafter, a terminator region TRM is formed behind the border-out BRDO immediately after the bordered region BRDA # 3 to shorten the time required for finalization. In the embodiment of FIG. 28 (c), it is necessary to fill with border-out BRDO until just before the extended replacement area ESPA, and this requires a long time for forming the border-out BRDO, resulting in a problem that it takes a finalization time. On the other hand, in the embodiment of FIG. 27 (c), a terminator region TRM having a relatively short length is set, and everything outside the terminator TRM is redefined as a new data lead-out region NDTLDO, and outside the terminator TRM. A certain unrecorded part is set in the use prohibited area 911. That is, when the data area DTA is finalized, the terminator area TRM is formed at the end of the recording data (immediately after the border-out BRDO). All the main data information in this area is set to “00h”. By setting the type information of this area as the attribute of the data lead-out NDTLDO, the terminator area TRM is redefined as a new data lead-out area NDTLDO as shown in FIG. The type information of this area is recorded in area type information 935 in the data ID as will be described later. That is, the region type information 935 in the data ID in the terminator region TRM is set to “10b” as shown in FIG. 30 to indicate that it is in the data lead-out DTLDO. The present embodiment is greatly characterized in that the identification information of the data lead-out position is set by the area type information 935 in the data ID. Consider the case where the information recording / reproducing unit 141 in the information recording / reproducing apparatus or information reproducing apparatus shown in FIG. 9 roughly accesses a specific target position on the recordable information storage medium. Immediately after the coarse access, the information recording / reproducing unit 141 needs to reproduce the data ID and decode the data frame number 922 in order to know where the write-once information storage medium has been reached. Since there is area type information 935 near the data frame number 922 in the data ID, it is immediately determined whether or not the information recording / reproducing unit 141 is in the data lead-out area DTLDO just by decoding the area type information 935 at the same time. Therefore, it is possible to simplify and speed up access control. As described above, by providing the identification information of the data lead-out area DTLDO by setting the data ID in the terminator area TRM, the terminator area TRM can be easily detected.

  As a special case, when the last border-out BRDO is set as an attribute of the data lead-out NDTLDO (that is, when the area type information 935 in the data ID of the data frame in the border-out BRDO area is set to “10b”). Does not set the terminator area TRM. Therefore, when the terminator area TRM having the data lead-out NDTLDO attribute is recorded, the terminator area TRM is regarded as a part of the data lead-out area NDTLDO, and thus recording to the data area DTA becomes impossible. As shown in (c), there are cases where the use prohibited area 911 remains.

  In this embodiment, the size of the terminator area TRM is changed depending on the position on the write-once information storage medium, thereby shortening the finalization time and improving the processing efficiency. This terminator area TRM is used not only to indicate the last position of the recorded data but also to prevent overrun due to track deviation even when used in a reproduction-only apparatus that detects track deviation by the DPD method. Therefore, the radial width of the terminator area TRM on the write-once information storage medium (the width of the portion filled with the terminator area TRM) is at least 0.05 mm or more due to the detection characteristics of the read-only device. Length is required. Since the length of one round on the write-once information storage medium differs depending on the radial position, the number of physical segment blocks included in one round differs depending on the radial position. For this reason, the size of the terminator area TRM differs depending on the radial position, that is, the physical sector number of the first physical sector in the terminator area TRM, and the size of the terminator area TRM increases toward the outer peripheral side. The minimum physical sector number of the terminator area TRM allowed must be larger than “04FE00h”. As described above, the first border area BRDA # 1 is composed of 4080 or more physical segment blocks, and the first border area BRDA # 1 in the radial direction on the write-once information storage medium is 1.0 mm or more. Comes from constraints for having to have a width. The terminator area TRM needs to start from the boundary position of the physical segment block.

  In FIG. 27 (d), the location where each information is recorded is set for each physical segment block size for the same reason as described above, and is distributed and recorded in 32 physical sectors in each physical segment block. A total of 64 KB of user data is recorded. A relative physical segment block number is set for each piece of information as shown in FIG. 27 (d), and each piece of information is sequentially recorded on the write-once information storage medium in ascending order of the relative physical segment block number. It has become a form. In the embodiment shown in FIG. 27, the RMD copies CRMD # 0 to # 4 having the same contents are multiplexed and written five times in the copy information recording area C_RMZ of the recorded contents in the recording position management zone of FIG. Yes. Thus, by overwriting, the reliability at the time of reproduction can be improved, and the copy information CRMD of the recorded contents in the recording position management zone can be reproduced stably even if dust or scratches are attached to the write-once information storage medium. The border end mark STB in FIG. 27 (d) matches the border end mark STB in FIG. 28 (d), but in the embodiment of FIG. 27 (d), as shown in the embodiment of FIG. 28 (d). It does not have the mark NBM indicating the next border. All the main data information in the reserved areas 901 and 902 is set to “00h”.

  At the beginning of the border-in BRDI, exactly the same information as the updated physical format information U_PFI is multiplexed and written six times from N + 1 to N + 6 as relative physical segment block numbers to form the updated physical format information U_PFI of FIG. ing. The reliability of information is improved by overwriting the updated physical format information U_PFI.

  FIG. 27 (d) is characterized in that the recording position management zone RMZ in the border zone is provided in the border-in BRDI. As shown in FIG. 24, the recording position management zone RMZ size in the data lead-in area DTLDI is relatively small, and the recording position recorded in the recording position management zone RMZ when the setting of a new border area BRDA is frequently repeated. The management data RMD is saturated, and it becomes impossible to set a new border area BRDA on the way. As shown in the embodiment of FIG. 27 (d), by providing the recording position management zone for recording the recording position management data RMD related to the subsequent in-border area BRDA # 3 in the border-in BRDI, a new in-border area As a result, BRDA can be set many times and the number of additional writings in the border area BRDA can be greatly increased. When the border area BRDA # 3 following the border-in BRDI including the recording position management zone RMZ in the border zone is closed or the data area DTA is finalized, an unrecorded state in the recording position management zone RMZ It is necessary to repeatedly record the last recording position management data RMD in all the reserved areas 273 (FIG. 26) and fill them all. This eliminates the reserved area 273 in the unrecorded state, prevents the track from being off (due to DPD) at the time of reproduction in the reproduction-only apparatus, and increases the reproduction reliability of the recording position management data RMD by multiple recording of the recording position management data RMD. Can be improved. All data in the reserved area 903 is set to “00h”.

  The border-out BRDO has a role of preventing overrun due to a track-off in a playback-only device on the premise of DPD, but the border-in BRDI has updated physical format information U_PFI and information on the recording position management zone RMZ in the border zone. There is no need to have a particularly large size other than having. Therefore, it is desired to reduce the size as much as possible in order to shorten the time (necessary for border zone BRDZ recording) when setting a new bordered area BRDA. In contrast to FIG. 27A, before the border-out BRDO is formed by border closing, the user data additional recording range 205 is sufficiently wide and the number of additional recordings is likely to be increased. Therefore, the recording position management zone RMZ in the border zone In FIG. 27, it is necessary to keep a large value of “M” in FIG. 27D so that the recording position management data can be recorded many times. In contrast, in FIG. 27B, in the state before the border-out area BRDA # 2 is bordered and before the border-out BRDO is recorded, the user data recordable range 205 is narrowed. It is considered that the number of times of recording position management data to be additionally recorded in the recording position management zone RMZ is not so much increased. Accordingly, the set size “M” of the recording position management zone RMZ in the border-in BRDI immediately before the bordered area BRDA # 2 can be relatively small. In other words, the estimated number of additional recording position management data is larger when the border-in BRDI is located on the inner circumference side, and the estimated additional number of additional recording position management data decreases toward the outer circumference. It has the feature of making it smaller on the outer peripheral side. As a result, the new border area BRDA setting time can be shortened and the processing efficiency can be improved.

  A logical recording unit of information recorded in the bordered area BRDA shown in FIG. 28C is referred to as an R zone. Therefore, one border area BRDA is composed of at least one R zone. In the current DVD-ROM, a file called “UDF bridge” in which both file management information compliant with UDF (Universal Disc Format) and file management information compliant with ISO9660 are simultaneously recorded in one information storage medium in the file system. The system is adopted. In the file management method based on ISO9660, there is a rule that one file must be recorded continuously in the information storage medium. That is, the information in one file is prohibited from being divided and arranged at discrete positions on the information storage medium. Therefore, for example, when information is recorded in conformity with the UDF bridge, all information constituting one file is continuously recorded. Therefore, there is an area in which this one file is continuously recorded. It is also possible to adapt to constitute one R zone.

  FIG. 29 shows a data structure in the control data zone CDZ and the R physical information zone RIZ. As shown in FIG. 29 (b), the control data zone CDZ includes physical format information (Physical Format Information) PFI and medium manufacturing related information (Disc Manufacturing Information) DMI, and the R physical information zone RIZ also includes a medium. It consists of manufacturing related information (Disc Manufacturing Information) DMI and R physical format information (R-Physical Format Information) R_PFI.

  In the medium manufacturing related information DMI, information 251 regarding the medium manufacturing country name and medium manufacturer affiliation country information 252 are recorded. In many cases, when a sold information storage medium is infringing on a patent, an infringement warning is issued to the country where the manufacturing site is located or the country where the information storage medium is consumed (used). By obligating the recording of the information in the information storage medium, the manufacturing location (country name) can be determined, and by making it easy to issue a patent infringement warning, intellectual property is guaranteed and technological advancement is promoted. Further, other medium manufacturing related information 253 is also recorded in the medium manufacturing related information DMI.

  The physical format information PFI or R physical format information R_PFI is characterized in that the type of information recorded by the recording location (relative byte position from the head) is defined. That is, the DVD family common information 261 is recorded in the 32-byte area from the 0th byte to the 31st byte as the recording location in the physical format information PFI or the R physical format information R_PFI, and the 32nd byte to the 127th byte. Up to 96 bytes are recorded common information 262 in the HD_DVD family that is the target of this embodiment, and 384 bytes from the 128th byte to the 511th byte are unique information about each standard type and part version. (Unique information) 263 is recorded, and information corresponding to each revision is recorded in 1536 bytes from the 512th byte to the 2047th byte. Thus, by sharing the information arrangement position in the physical format information according to the information content, the location of the recorded information is made common regardless of the type of the medium, so the information reproducing apparatus or information recording / reproducing apparatus The reproduction process can be shared and simplified. As shown in FIG. 29 (d), common information 261 in the DVD family recorded from the 0th byte to the 31st byte is further read-only information storage recorded from the 0th byte to the 16th byte. Information 267 recorded in common on all media, rewritable information storage media and write-once information storage media, and recorded on rewritable information storage media and write-once information storage media in the 17th to 31st bytes Then, it is divided into information 268 which is not recorded in the reproduction-only form.

  FIG. 31 shows another embodiment relating to the data structure in the control data zone shown in FIG. As shown in FIG. 23C, the control data zone CDZ is configured as a part of the embossed pit area 211. This control data zone CDZ is composed of 192 data segments starting with the physical sector number 151296 (024F00h). In the embodiment of FIG. 31, two control data sections CTDS composed of 16 data segments and two copyright data sections CPDS composed of 16 data segments are respectively arranged in the control data zone CDZ, and the reserved area RSV is interposed between them. Is set. By arranging two locations, the reliability of the recorded information is improved, and by arranging the reserve area RSV between them, the physical distance between the two locations is increased, and the burst error caused by a scratch on the surface of the information storage medium is prevented. The impact is reduced.

  In one control data section CTDS, as shown in FIG. 31 (c), the first three physical sector information with relative physical sector numbers “0” to “2” are repeatedly recorded 16 times. ing. Thus, the reliability of the recorded information is improved by overwriting 16 times. The physical format information PFI described in Table 8 or Table 19 is recorded in the first physical sector in the data segment whose relative physical sector number is “0”. The medium manufacturing related information DMI is recorded in the second physical sector in the data segment whose relative physical sector number is “1”. Further, the copyright protection information CPI is recorded in the third physical sector in the data segment whose relative physical sector number is “2”. Reserved areas RSV having relative physical sector numbers “3” to “31” are reserved for use in the system.

As the contents of the above medium manufacturing related information DMI, the medium manufacturer name (Disc Manufacturer's name) is recorded in 128 bytes from the 0th byte to the 127th byte.
Location information (information indicating where this medium was manufactured) is recorded in 128 bytes from the 128th byte to the 255th byte.

  The media manufacturer name is described in ASCII code. However, ASCII codes that can be used as media manufacturer names are limited to "0Dh" and from "20h" to "7Eh". The name of the medium manufacturer is described from the first byte in this area, and the remaining part in this area is filled with “0Dh” data (terminated). Alternatively, as another description method, the size that can be described as the media manufacturer name is set to the range from the beginning to “0Dh”, and if the media manufacturer name is longer than that, it is truncated to “0Dh” and after “0Dh” May be filled with “20h” data.

  In the location information where the media manufacturer is present indicating where this media is manufactured, the corresponding country name or region is described in ASCII code. In this area as well as the media manufacturer name, usable ASCII codes are limited to “0Dh” and “20h” to “7Eh”. The location information where the media manufacturer exists is described from the first byte in this area, and the remaining part in this area is filled (terminated) with “0Dh” data. Alternatively, as another description method, the size that can be described as the location information where the media manufacturer exists is set to a range from the beginning to “0Dh”, and when the location information where the media manufacturer exists is longer than that, “0 Dh” is reached. And after “0Dh”, it may be filled with “20h” data.

  The reserve area RSV in FIG. 31C is entirely filled with “00h” data.

  Comparison between the specific information contents in the physical format information PFI or the R physical format information R_PFI shown in FIG. 29 or FIG. Table 8 shows.

  Information 267 recorded in common for all of the read-only type, rewrite type, and write-once type in the common information 261 within the DVD family is the type of standard document (reproduction only / rewrite / Append) information and version number information, medium size (diameter) and maximum possible data transfer rate information, medium structure (single layer or double layer, embossed pit / additional area / rewrite area), recording density (linear density and Track density) information, data area DTA arrangement location information, and burst cutting area BCA presence / absence information (all in the present embodiment) are recorded.

  Revision number information that specifies the maximum recording speed sequentially from the 28th byte to the 31st byte as the information 268 that is common information 261 within the DVD family and is recorded in both the rewritable and write-once types, and the maximum recording speed is specified Revision number information, revision number table (application revision number), class state information, and extended (part) version information are recorded. The feature of this embodiment is that the information from the 28th byte to the 31st byte is provided with revision information corresponding to the recording speed in the recording area of the physical format information PFI or R physical format information R_PFI. Yes. Conventionally, when a medium that increases the recording speed on the medium, such as double speed or quadruple speed, has been developed, it has been very troublesome to recreate a new standard each time. On the other hand, in this embodiment, the contents are largely changed, and the standard document (version book) that changes the version when it becomes, and the revision book that changes and issues the revision corresponding to the small change such as the recording speed, Only the revision book that only updates the revision is issued each time the recording speed is improved. This guarantees an extended function for future high-speed recording-compatible media and can support the standard with a simple method called revision, so that when a new high-speed recording-compatible medium is developed, it will be possible to respond at high speed. There is an effect to say. In particular, the revision number information column that specifies the maximum recording speed of the 17th byte and the revision number information column that specifies the minimum recording speed of the 18th byte are provided separately, so that the revision number is the highest and lowest recording speed. The feature of this embodiment lies in the fact that it can be set separately. For example, when a recording film capable of recording at a very high speed is developed, the recording film can be recorded at a very high speed. Recording films that can be lowered are often very expensive. On the other hand, by making it possible to set the revision number separately for the highest and lowest recording speeds as in this embodiment, the selection range of developable recording films is expanded, and as a result, higher speed recording is possible. There is an effect that a medium or a lower-priced medium can be supplied. The information recording / reproducing apparatus of this embodiment has information on the highest possible recording speed and the lowest possible recording speed for each revision in advance. When the information recording medium is applied to the information recording / reproducing apparatus, first, the information recording / reproducing unit 141 shown in FIG. 9 reads the information in the physical format information PFI or R physical format information R_PFI, and the obtained revision number information is obtained. The maximum possible recording speed of the information storage medium mounted with reference to the information on the maximum possible recording speed and the minimum possible recording speed for each revision previously recorded in the memory unit 175 in the control unit 143. The lowest possible recording speed is determined, and as a result, recording is performed at the optimum recording speed.

  Next, the type of each standard document from the 128th byte to the 511th byte shown in FIG. 29C, the meaning of the version-specific information 263, and the unique setting for each revision from the 512th byte to the 2047th byte. The meaning of the possible information content 264 will be described. In other words, in the standard information type and version specific information 263 from the 128th byte to the 511th byte, the meaning of the recorded information content at each byte position is different between the rewritable information storage medium and the recordable information storage medium. Regardless, the information content 264 that can be set uniquely for each revision from the 512th byte to the 2047th byte is not only the difference between the rewritable information storage medium and the write-once information storage medium but of the same type. Even in the medium, if the revision is different, the meaning of the recorded information content at each byte position is allowed to be different.

  As shown in Table 8, as information in the specific information 263 of the type and version of each standard in which the meaning of the recorded information content at each byte position is the same in the rewritable information storage medium and the recordable information storage medium of different types Sequentially, medium manufacturer name information, additional information from the medium manufacturer, recording mark polarity (identification of “H → L” or “L → H”) information, linear velocity information during recording or playback, circle The rim intensity value of the optical system along the circumferential direction, the rim intensity value of the optical system along the radial direction, and the recommended laser power during reproduction (a light amount value on the recording surface) are recorded.

  In particular, the present embodiment is characterized in that the recording mark polarity (identification of “H → L” or “L → H”) information (Mark Polarity Descriptor) is provided at the 192nd byte. In conventional rewritable or write-once DVD discs, the amount of reflected light in the recording mark decreases (Low) (H → L) (High to Low) compared to the unrecorded state (reflection level is relatively high: High). Only the recording film was recognized. On the other hand, if demands such as “high-speed recording support”, “cost reduction” or physical performance “decrease in cross erase” or “increase in the upper limit of the number of rewrites” are made to the medium, There arises a problem that the “H → L” recording film alone cannot cope with it. On the other hand, in the present embodiment, not only the “H → L” recording film but also the “L → H” recording film in which the amount of light reflection increases in the recording mark is allowed. "L → H" recording films as well as "" are incorporated into the standard, and the effect of being able to supply high-speed recording and low-priced media by expanding the selection range of recording films is produced.

  A specific information recording / reproducing apparatus mounting method will be described below. Both the reproduction signal characteristic from the “H → L” recording film and the reproduction signal characteristic from the “L → H” recording film are written together in the standard document (version book) or revision book, and the PR of FIG. Two corresponding circuits are prepared in the circuit 130 and the Viterbi decoder 156, respectively. When an information storage medium is loaded in the information reproducing unit 141, first, the slice level detection circuit 132 for reading information in the system lead-in area SYLDI is activated. The slice level detection circuit 132 reads the polarity (identification of “H → L” or “L → H”) information of the recording mark recorded at the 192nd byte, and then reads “H → L” or “L → After determining whether it is H ″ and switching the circuits in the PR equalization circuit 130 and the Viterbi decoder 156 accordingly, the information recorded in the data lead-in area DTLDI or the data area DTA is reproduced. By the above method, information in the data lead-in area DTLDI or the data area DTA can be read relatively quickly and accurately. The revision number information defining the maximum recording speed is described in the 17th byte and the revision number information defining the minimum recording speed is described in the 18th byte. However, the information is only range information defining the maximum and minimum. In the case of recording most stably, optimum linear velocity information is required at the time of recording, and the information is recorded at the 193rd byte.

The rim intensity value of the optical system along the circumferential direction of the 194th byte as optical system condition information at a position preceding various recording condition (write strategy) information included in the information content 264 that can be set uniquely for each revision The rim intensity value information of the optical system along the radial direction of the 195th byte is arranged in the following major feature of this embodiment. These pieces of information mean the condition information of the optical system of the optical head used when determining the recording condition arranged on the rear side. Rim intensity means the distribution of incident light incident on the objective lens before focusing on the recording surface of the information storage medium,
“Intensity value at the objective lens peripheral position (outer pupil position) when the center intensity of the incident light intensity distribution is“ 1 ””
Defined by The intensity distribution of incident light on the objective lens is not point-symmetric but elliptical distribution, and the rim intensity value differs between the radial direction and the circumferential direction of the information storage medium, so two values are recorded. The larger the rim intensity value, the smaller the condensing spot size on the recording surface of the information storage medium. Therefore, the optimum recording power condition greatly varies depending on the rim intensity value. Since the information recording / reproducing apparatus knows in advance the rim intensity value information of the optical head it has, first the rim intensity of the optical system along the circumferential direction and radial direction recorded in the information storage medium. Read the city value and compare it with the value of your optical head. If there is no significant difference in the comparison result, the recording condition recorded on the back side can be applied. It is necessary to start the determination of the optimum recording conditions while performing trial writing by the recording / reproducing apparatus itself using the drive test zone DRTZ described in No. 25.

  In this way, it is necessary to quickly determine whether to use the recording condition recorded on the back side or ignore the information and start to calculate the optimum recording condition while performing trial writing. As shown in Table 8, the rim intensity information can be read first by placing the condition information of the optical system that determined the condition at the preceding position with respect to the position where the recommended recording condition is recorded. Thus, there is an effect that it can be determined at high speed whether or not the recording conditions to be arranged later can be met.

  As described above, in the present embodiment, the contents are largely changed, and the standard document (version book) that changes the version when it is changed and the revision book that is issued by changing the revision corresponding to the small change such as the recording speed, Every time the recording speed is improved, only the revision book in which only the revision is updated can be issued. Accordingly, since the recording conditions in the revision book change when the revision numbers are different, the information content 264 that can be set uniquely for each revision from the 512th byte to the 2047th byte, mainly regarding the recording condition (write strategy). Is recorded in. As is apparent from Table 8, the information contents 264 that can be set uniquely for each revision from the 512th byte to the 2047th byte are the same as the difference between the rewritable information storage medium and the recordable information storage medium of different types. Even for different types of media, it is allowed that the meaning of the recorded information content at each byte position differs if the revision is different.

  The definitions of peak power, bias power 1, bias power 2, and bias power 3 in Table 8 coincide with the power values defined in FIG. In Table 8, the first pulse end time means TEFP defined in FIG. 16, the multi-pulse interval means TMP defined in FIG. 16, and the last pulse start time defined in FIG. TSLP means the bias power 2 period of the 2T mark means the TLC defined in FIG.

  Another embodiment regarding the data structure in the physical format information and R physical format information shown in Table 8 is shown in Table 19. In Table 19, the “updated physical format information” is also compared and described. In Table 19, the 0th to 31st bytes are used as a recording area for common information 269 in the DVD family, and the 32nd and subsequent bytes are set for each standard.

  In the write-once information storage medium, as shown in FIG. 23C, R physical format information (R-physical format information) recorded in the R physical information zone RIZ in the data lead-in area DTLDI is the physical format information PFI ( The start position information of the border zone (the outermost peripheral address of the first border) is added to the HD_DVD family common information) and recorded. In the updated physical format information U_PFI in the border-in BRDI shown in FIG. 28D or FIG. 27D, the start position information (self (outermost address of border) is added and recorded. In Table 8, this border zone start position information is arranged from the 197th byte to the 204th byte, whereas in the embodiment shown in Table 19, information on recording conditions such as peak power and bias power 1 (each The information content 264) that can be set uniquely for each revision is characterized by a position that precedes the 133th to 140th bytes, which is a position that precedes the common information 269 in the DVD family. . Similarly to the border zone start position information, the updated start position information is a position preceding information related to recording conditions such as peak power and bias power 1 (information content 264 that can be set uniquely for each revision), and DVD. It is arranged from the 133rd byte to the 140th byte, which is the position after the common information 269 in the family. As a result of the future revision number being increased and more accurate recording conditions being sought, there is a possibility that the 197th to 207th bytes are used as the recording condition information of the rewritable information storage medium. In this case, when the start position information of the border zone of the R physical format information recorded in the write-once information storage medium is arranged from the 197th byte to the 204th byte as in the embodiment of Table 8, the arrangement of the recording conditions There is a risk that the correspondence (compatibility) between the rewritable information storage medium and the write-once information storage medium related to the position is lost. As shown in Table 19, even if the amount of information related to future recording conditions increases by arranging the start position information of the border zone and the updated start position information from the 133rd byte to the 140th byte, it is additionally recorded as a rewritable information storage medium. There is an effect that it is possible to ensure correspondence (compatibility) of recording positions between various types of information storage media. The specific information content regarding the start position information of the border zone is that the start position information of the border-out BRDO outside the (current) bordered area BRDA currently used from the 133rd byte to the 136th byte is the physical sector number ( PSN (Physical Sector Number) is described. From the 137th byte to the 140th byte, the start position information of the border-in BRDI related to the border area BRDA to be used next is described as a physical sector number (PSN).

  The specific information content related to the updated start position information indicates the latest border zone position information when the border area BRDA is newly set, and is currently used from the 133rd byte to the 136th byte (the current ) The start position information of the border-out BRDO outside the bordered area BRDA is described by a physical sector number (PSN), and the 137th to 140th bytes are related to the bordered area BRDA to be used next. Border start BRDI start position information is described by a physical sector number (PSN). When the next bordered area BRDA cannot be recorded, all of this (from the 137th byte to the 140th byte) are filled with “00h”.

  Compared with the embodiment shown in Table 8, in the embodiment of Table 19, “media manufacturer name information” and “additional information from the media manufacturer” are deleted, and the polarity of the recording mark (“H → L” from the 128th byte). "Identification of" "or" L → H ") information is arranged.

  Table 9 shows a detailed comparison of information recorded in the location information of the data area DTA recorded in the 4th to 15th bytes in Table 8 or Table 19.

  The start position information of the data area DTA is recorded in common without distinction between the medium type, the physical format information PFI, and the R physical format information R_PFI. As information indicating the end position, end position information of the data area DTA is recorded in the read-only information storage medium.

  In the physical format information PFI of the recordable information storage medium, the last position information of the recordable range of user data is recorded. For example, in the example shown in FIG. Means position.

  On the other hand, in the R physical format information R_PFI of the write-once information storage medium, the last position information of the recorded data in the corresponding border area BRDA is recorded.

  In addition, in the read-only information storage medium, the last address information in the “0 layer” that is the previous layer as viewed from the reproduction side optical system, and each start between the land area and the groove area in the rewritable information storage medium Information on the difference value of the position information is also recorded.

  As shown in FIG. 23C, a recording position management zone RMZ exists in the data lead-in area DTLDI. As shown in FIG. 28 (d), the copy information also exists in the border-out BRDO as copy information C_RMZ of the recorded contents in the recording position management zone. In this recording position management zone RMZ, as shown in FIG. 24B, recording management data RMD having the same data size as one physical segment block size is recorded, and the recording position management data RMD is recorded. Each time the contents are updated, it can be added to the back sequentially as new recording position management data RMD updated. Table 10, Table 11, Table 12, Table 13, Table 14, Table 15 show the detailed data structure in this one recording position management data RMD.

  The recording position management data RMD is further divided into fine RMD field information RMDF having a size of 2048 bytes.

  The first 2048 bytes in the recording position management data RMD is a reserved area.

  In the next 2048 byte size RMD field 0, the recording position management data format code information, whether the target medium is (1) unrecorded, (2) during recording before finalization, or (3) after finalization Medium status information indicating whether or not, a unique disk ID (disk identification information), arrangement position information of the data area DTA, arrangement position information of the latest (updated) data area DTA, arrangement position information of the recording position management data RMD Are arranged sequentially. In the arrangement position information of the data area DTA, the start position information of the data area DTA and the recordable range of the user data at the initial time are shown as information indicating the user data recordable range 204 (FIG. 25D) in the initial state. 204 of final position information (in the embodiment of FIG. 25 (d), this information indicates the position immediately before the β point) is recorded.

In this embodiment, as shown in FIGS. 25 (e) and 25 (f), the extended drive test zone EDRTZ and the extended replacement area ESPA can be additionally set in the additionally recordable range 204 of user data. However, when it is expanded in this way, the user data appendable range 205 becomes narrower. The following features of the present embodiment are such that related information is recorded in “the latest (updated) data area DTA arrangement position information” so that user data is not added to the extended areas EDRTZ and ESPA by mistake. There is. That is, it can be determined whether or not the extended drive test zone EDRTZ has been added by the presence / absence identification information of the extended drive test zone EDRTZ, and whether or not the extended replacement area ESPA has been added by the presence / absence identification information of the extended replacement area ESPA. Further, as recordable range information related to the additionally recordable range 205 of the user data managed in the recording position management data RMD, as shown in Table 10, the latest (updated) data location DTA location information in the RMD field 0 Since the last position of the recordable range 205 of the latest user data recorded in is present, the additionally recordable range 205 of the user data shown in FIG. The size (unrecorded remaining amount) can be detected at high speed. As a result, for example, it is possible to record in the medium with the highest image quality that can be realized by setting the optimum transfer rate at the time of recording according to the recording reservation time specified by the user and without any omission in the recording reservation time specified by the user. The effect is said. Taking the embodiment of FIG. 25D as an example, the above-mentioned “final position of the recordable range 205 of the latest user data” means the position immediately before the ζ point. Instead of describing the position information by the physical sector number, it is possible to describe the position information by an ECC block address number as another embodiment. As will be described later, in this embodiment, one ECC block is composed of 32 sectors. Therefore, the lower 5 bits of the physical sector number of the sector arranged at the head in the specific ECC block coincide with the sector number of the sector arranged at the head position in the adjacent ECC block. When the physical sector number is set so that the lower 5 bits of the physical sector number of the sector arranged at the head in the ECC block becomes “00000”, the physical sector numbers of all sectors existing in the same ECC block The values in the lower 6th bit and above of the match. Therefore, the lower 5-bit data of the physical sector number of the sector existing in the same ECC block is removed, and the address information obtained by extracting only the data of the lower 6 bits or more is referred to as ECC block address information (or ECC block address number). Define. As will be described later, since the data segment address information (or physical segment block number information) recorded in advance by wobble modulation matches the ECC block address, the position information in the recording position management data RMD is described by the ECC block address number. Then, (1) Access to unrecorded areas is particularly speeded up. Since the position information unit in the recording position management data RMD matches the information unit of the data segment address recorded in advance by wobble modulation, the difference calculation process is easy. (2) The management data size in the recording position management data RMD can be reduced. This produces an effect that the number of bits necessary for address information description can be saved by 5 bits per address. As will be described later, one physical segment block length coincides with one data segment length, and user data for one ECC block is recorded in one data segment. Therefore, “ECC block address number”, “ECC block address” or “data segment address”, “data segment number”, “physical segment block number”, etc. are expressed as addresses, all of which are synonyms. Meaningful.

As shown in Table 10, the arrangement position information of the recording position management data RMD in the RMD field 0 includes size information set in the recording position management zone RMZ in which the recording position management data RMD can be sequentially added. Recorded in units or physical segment block units. As shown in FIG. 24B, since one recording position management zone RMD is recorded for each physical segment block, the information is updated (updated) in the recording position management zone RMZ with this information. ) Can be added to the recorded position management data RMD. Next, the current recording position management data number in the recording position management zone RMZ is recorded. This means the number information of the recording position management data RMD already recorded in the recording position management zone RMZ. For example, assuming that this information is information in the recording position management data RMD # 2 as an example shown in FIG. 24B, this information is the recording position management data RMD recorded second in the recording position management zone RMZ. A value of “2” is recorded in this field. Next, remaining amount information in the recording position management zone RMZ is recorded. This information means information on the number of recording position management data RMD that can be further added in the recording position management zone RMZ, and is described in units of physical segment blocks (= ECC block units = data segment units). Between the above three information [size information set in RMZ]
= [Current recording position management data number] + [Remaining amount in RMZ]
The relationship is established. The present embodiment is characterized in that the used amount or remaining amount information of the recording position management data RMD in the recording position management zone RMZ is recorded in the recording area of the recording position management data RMD.

  For example, when all the information is recorded on one recordable information storage medium at a time, the recording position management data RMD may be recorded only once, but it is very much recorded on one recordable information storage medium. When it is desired to repeatedly record additional user data (addition of user data in the user data additional recordable range 205 in FIG. 25 (f)) repeatedly, the recording position management data RMD updated for each additional recording is additionally recorded. There is a need to do. In this case, if the recording position management data RMD is frequently added, the reserved area 273 shown in FIG. 24B disappears, and the information recording / reproducing apparatus needs to take good measures against it. Therefore, by recording the used amount or remaining amount information of the recording position management data RMD in the recording position management zone RMZ in the recording area of the recording position management data RMD, it is impossible to additionally write in the recording position management zone RMZ area. Is known in advance, and the information recording / reproducing apparatus can be dealt with early.

  The present embodiment is characterized in that the data lead-out area DTLDO can be set in a form including the extended drive test zone EDRTZ as shown in the transition from FIG. 25 (e) to (f). (FIG. 1 (E4)). At this time, the start position of the data lead-out area DTLDO changes from the β point to the ε point in FIG. In order to manage this situation, a column for recording start position information of the data lead-out area DTLDO is provided in the arrangement position information of the latest (updated) data area DTA in the RMD field 0 of Table 10. As described above, the drive test (trial writing) is basically recorded in units of clusters that can be expanded in units of data segments (ECC blocks). Therefore, although the start position information of the data lead-out area DTLDO is described by the ECC block address number, as another embodiment, the physical sector number or the physical segment block number of the first physical sector arranged in the first ECC block It is also possible to describe with a data segment address and ECC block address.

  In the RMD field 1, history information of the information recording / reproducing apparatus that has recorded the corresponding medium is recorded. For each information recording / reproducing apparatus, manufacturer identification information, serial number and model number described in ASCII code, drive The date / time information on the recording power adjustment using the test zone and the recording condition information performed at the time of additional writing are described according to the format of all the recording condition information in the information 264 (Table 8) that can be set uniquely for each revision. It has become.

  The RMD field 2 is a user use area, for example, so that the user can record information of recorded content (to be recorded).

  In the RMD field 3, start position information of each border zone BRDZ is recorded. That is, as shown in Table 11, the start position information of the border-out BRDO from the first to the 50th is described by the physical sector number.

  For example, in the embodiment shown in FIG. 28C, the start position of the first border-out BRDO indicates the position of the point η, and the start position of the second border-out BRDO indicates the position of the point θ.

  In the RMD field 4, position information of the extended drive test zone is recorded. First, the last position information of the place already used for test writing in the drive test zone DRTZ in the data lead-in area DTLDI described in FIG. 24C and the information described in FIGS. In the drive test zone DRTZ in the data lead-out area DTLDO, the last position information of the place already used for test writing is recorded. In the drive test zone DRTZ, test writing is sequentially performed from the inner circumference side (the smaller physical sector number) toward the outer circumference direction (the direction in which the physical sector number increases). As will be described later, the location unit used for the trial writing is performed in units of clusters, which are additional write units, and thus becomes an ECC block unit. Therefore, it is described by the ECC block address number as the last position information of the place already used for the test writing, or when it is described by the physical sector number, it is arranged at the end of the ECC block used for the test writing. The physical sector number of the physical sector is described. Since the place used for the trial writing has already been recorded, when the trial writing is performed next, the trial writing is performed after the last position already used for the trial writing. Therefore, the information recording / reproducing apparatus then starts test writing from where the last position information (= used amount in the drive test zone DRTZ) of the place already used for test writing in the drive test zone DRTZ is used. In addition to immediately knowing whether or not it should be done, it can be determined from the information whether or not there is a free space in the drive test zone DRTZ that can be written next. Within the drive test zone DRTZ in the data lead-in area DTLDI, area size information that can be additionally written by trial or flag information indicating whether or not this drive test zone DRTZ has been used up and the drive test zone in the data lead-out area DTLDO Area size information that can be additionally written by trial in the DRTZ, or flag information indicating whether or not the drive test zone DRTZ has been used up is recorded. Since the size of the drive test zone DRTZ in the data lead-in area DTLDI and the size of the drive test zone DRTZ in the data lead-out area DTLDO are known in advance, the drive test zone DRTZ in the data lead-in area DTLDI or the data lead-out area In the drive test zone DRTZ in the area DTLDO, it is possible to determine the size (remaining amount) of the area where further test writing can be performed in the drive test zone DRTZ only by the last position information of the place already used for test writing. However, by having this information in the recording position management data RMD, the remaining amount in the drive test zone DRTZ can be immediately known, and the time required for determining whether or not the extended drive test zone EDRTZ is newly set can be shortened. As another embodiment, in this field, flag information indicating whether or not the drive test zone DRTZ has been used is recorded in place of the area size (remaining amount) information that can be additionally test-written in the drive test zone DRTZ. You can also If a flag that tells you that it has already been used up is set, you can eliminate the risk of accidentally attempting test writing in this area.

  In the RMD field 4, the additional set number of times information of the extended drive test zone EDRTZ is recorded next. In the embodiment shown in FIG. 25 (e), since the extended drive test zone EDRTZ is set at two locations of the extended drive test zone 1 EDRTZ1 and the extended drive test zone 2 EDRTZ2, “the number of additional settings of the extended drive test zone EDRTZ = 2. " Further, in the field 4, range information for each extended drive test zone EDRTZ and range information already used for test writing are recorded. In this way, the position information of the extended drive test zone can be managed in the recording position management data RMD, so that the extended setting of the extended drive test zone EDRTZ can be performed a plurality of times and the recording position in the recordable information storage medium can be set. The location information of the extended drive test zone EDRTZ, which has been sequentially expanded in the form of update addition of the management data RMD, can be managed accurately, and it is erroneously determined that the user data can be additionally recorded 204 (FIG. 25 (d)). The risk of overwriting user data on the test zone EDRTZ can be eliminated. As described above, the trial writing unit is also recorded in cluster units (ECC block units), so the range for each extended drive test zone EDRTZ is designated in ECC block address units. In the embodiment shown in FIG. 25 (e), since the start position information of the extended drive test zone EDRTZ set first is that the extended drive test zone 1 EDRTZ1 is set first, the γ point is indicated and the extended drive test zone set first is set. The end position information of EDRTZ corresponds to the position immediately before the β point. The unit of position information is also described by an ECC block address number or a physical sector number. In the embodiments of Tables 10 and 11, the end position information of the extended drive test zone EDRTZ is shown, but not limited thereto, the size information of the extended drive test zone EDRTZ may be described instead. In this case, the size of the extended drive test zone 1 EDRTZ1 set first is “β-γ”. The last position information of the place already used for trial writing in the extended drive test zone EDRTZ set first is also described by the ECC block address number or the physical sector number. Subsequently, area size (remaining amount) information that can be additionally written by trial in the extended drive test zone EDRTZ set first is recorded. Since the size of the extended drive test zone 1 EDRTZ1 and the size of the area already used therein are already known from the above information, an area size (remaining amount) that can be further additionally written by trial is automatically calculated. By providing a column, you can immediately know whether or not the current drive test zone is sufficient when performing a new drive test (trial writing), and shorten the time taken to determine additional settings for the extended drive test zone EDRTZ it can. In this column, area size (remaining amount) information that can be additionally written by trial can be recorded. As another embodiment, flag information indicating whether or not this extended drive test zone EDRTZ has been used up is recorded in this column. It is also possible to set to. If a flag that can be instantly recognized as having been used up is set, the risk of erroneously trying test writing in this area can be eliminated.

  An example of a processing method for newly setting an extended drive test zone EDRTZ in the information recording / reproducing apparatus shown in FIG.

(1) A write-once information storage medium is mounted on an information recording / reproducing apparatus. (2) Data formed in the burst cutting area BCA is reproduced by the information recording / reproducing unit 141 and sent to the control unit 143. Determining whether the transferred information is decoded and proceeding to the next step → (3) The information recording / reproducing unit 141 reproduces the information recorded in the control data zone CDZ in the system lead-in area SYLDI, and the control unit 143 (4) The rim intensity value (194th and 195th bytes in Table 8) when the recommended recording condition is determined in the control unit 143 and the rim of the optical head used in the information recording / reproducing unit 141 The intensity values are compared, and the area size necessary for the trial writing is determined. (5) Information in the recording position management data is reproduced by the information recording / reproducing unit 141, and the control unit 1 Send to 3. The control unit decodes the information in the RMD field 4 and determines whether there is a margin for the area size necessary for the trial writing determined in (4). If there is a margin, proceed to (6), if there is no margin Go to (9) → (6) From this RMD field 4, write the current trial writing from the last position information of the location already used for trial writing in the drive test zone DRTZ or extended drive test zone EDRTZ used for trial writing. Determine where to start → (7) Perform trial writing for the size determined in (4) from the location determined in (6) → (8) Because the number of places used for trial writing increased due to the process in (7) The recording position management data RMD in which the last position information of the place already used for the trial writing has been rewritten is temporarily stored in the memory unit 175, and the process proceeds to (12) → (9) RMD field 0 recorded in the “last position of the recordable range 205 of the latest user data” information or “location data of the data area DTA in the physical format PFI shown in Table 9” The information recording / reproducing unit 141 reads “the last position information in the additionally recordable range”, and further sets the range of the extended drive test zone EDRTZ to be newly set in the control unit 143 → (10) Based on the result of (9) The information of “the last position of the recordable range 205 of the latest user data” recorded in the attached RMD field 0 is updated and the additional setting number information of the extended drive test zone EDRTZ in the RMD field 4 is incremented by 1 (number of times 1) and add the start / end position information of the extended drive test zone EDRTZ to be newly set. The added recording position management data RMD is temporarily stored in the memory unit 175.fwdarw. (11) .fwdarw. (7) .fwdarw. (12) .fwdarw. (12). Optimal recording obtained as a result of the trial writing performed in (7). Necessary user information is added in the user data additional recordable range 205 under the condition. → (13) The start / end position information (Table 13) in the R zone newly generated corresponding to (12) is added. The updated recording position management data RMD is temporarily stored in the memory unit 175. (14) The latest recording position management data RMD which is controlled by the control unit 143 and the information recording / reproducing unit 141 is temporarily stored in the memory unit 175. Additional recording is performed in the reserved area 273 (for example, FIG. 24B) in the recording position management zone RMZ. As shown in Table 13, the RMD field 5 contains the position information of the extended replacement area ESPA. It is recorded. The replacement area can be expanded in the write-once information storage medium, and the position information of the replacement area is managed by the position management data RMD. In the embodiment shown in FIG. 25 (e), since the extended replacement area ESPA is set at two locations of the extended replacement area 1 ESPA1 and the extended replacement area 2 ESPA2, the “extended replacement area ESPA” described first in the RMD field 5 is set. The number of additional settings for “2” is “2”. The start position information of the first extended replacement area ESPA set is the δ point position, the end position information of the first extended replacement area ESPA is the position immediately before the γ point, and the start position information of the second extended replacement area ESPA is set. Is the position of the ζ point, and the end position information of the second extended substitution area ESPA set corresponds to the position immediately before the ε point.

In the RMD field 5 of Table 13, information relating to defect management is recorded. In the first column in the RMD field 5 of Table 13, the number information of ECC blocks or the number of physical segment blocks already used for replacement in the replacement area adjacent to the data lead-in area DTLDI is recorded. In the present embodiment, replacement processing is performed in units of ECC blocks for defective areas found within the user data appendable range 204. As will be described later, since one data segment constituting one ECC block is recorded in one physical segment block area, the number of replacements already performed is the number of ECC blocks used for replacement (or the number of physical segment blocks). , The number of data segments). Therefore, the unit of the description information in this column is an ECC block unit, a physical segment block unit, or a data segment unit. In the write-once information storage medium, locations used as replacement processing in the replacement area SPA or the extended replacement area ESPA are often used sequentially from the inner periphery side where the ECC block address number is smaller. Therefore, in this embodiment, the ECC block address number can be described as the last position information of the used place for replacement in this embodiment. As shown in Table 13, the same information ("ECC block already used for replacement in the first extended replacement area ESPA" in the extended replacement area 1 ESPA1 set first and the extended replacement area 2 ESPA2 set second. Number information or physical segment block number information or the last location information (ECC block address number) of the used place for replacement and the number of ECC blocks already used for replacement in the second extended replacement area ESPA There is a column for recording information, physical segment block number information, or last location information (ECC block address number) ") of a used place for replacement. Using this information (1) The next replacement location to be newly set for the defective area found in the user data appendable range 205 is immediately known when the replacement processing is performed next time. Last of used locations for replacement (2) The remaining amount in the replacement area SPA or the extended replacement area ESPA is obtained by calculation, and (if the remaining capacity is insufficient), the new extended replacement area ESPA is set. There is an effect that it can be understood whether or not it is necessary. Since the size of the replacement area SPA adjacent to the data lead-in area DTLDI is known in advance, if there is information regarding the number of ECC blocks used for replacement in the replacement area SPA, the remaining amount in the replacement area SPA However, it is possible to immediately know the remaining amount by providing a recording frame for the number of unused ECC blocks or the number of physical segment blocks that can be used for replacement, which is remaining amount information in the replacement area SPA. Further, it is possible to reduce the time required for determining whether or not there is a necessity for setting regarding the extended replacement area ESPA. For the same reason, there is provided a frame capable of recording “remaining amount information in the expanded replacement area ESPA set first” and “remaining amount information in the extended replacement area ESPA set second”. In this embodiment, the replacement area SPA can be expanded in the write-once information storage medium, and the position information is managed in the recording position management data RMD. As shown in FIG. 25 (e), the extension substitution area 1 ESPA1, the extension substitution area 2 ESPA2, and the like can be extended and set at an arbitrary start position and an arbitrary size as required within the user data recordable range 204. Therefore, the additional setting number information of the extended replacement area ESPA is recorded in the RMD field 5, and the start position information of the first extended replacement area ESPA and the start position information of the second extended replacement area ESPA can be set. It has become. The start position information is described by a physical sector number or an ECC block address number (or a physical segment block number or a data segment address). In the embodiments of Tables 10 and 11, “first end position information of the extended replacement area ESPA” and “second end position information of the extended replacement area ESPA” are defined as information defining the range of the extended replacement area ESPA. However, as another embodiment, the size information of the extended replacement area ESPA is the number of ECC blocks, the number of physical segment blocks, the number of data segments, the number of ECC blocks or the number of physical sectors instead of the end position information. It is also possible to record in.

In the RMD field 6, defect management information is recorded. In this embodiment, as a method for improving the reliability of information recorded on an information storage medium related to defect processing, (1) a conventional “alternate mode” in which information scheduled to be recorded at a defect location is recorded at an alternative location; ) "Multiplexing mode" that improves the reliability by recording the same information twice in different locations on the information storage medium
As shown in Table 14, “Defect management process type information” in the secondary defect list entry information in the recording position management data RMD is shown in Table 14. Recorded in. The contents in the secondary defect list entry information are as follows: (1) In the case of the replacement mode: • Type information of defect management processing is set to “01” (similar to the conventional DVD-RAM),
“Replacement source ECC block position information” means the position information of an ECC block found as a defective place in the user data recordable range 205, and information that is originally scheduled to be recorded is not recorded here, but is a replacement area. It is recorded inside.

“Position information of replacement destination ECC block” indicates the position information of the replacement place set in the replacement area SPA or extended replacement area 1 ESPA1 and extended replacement area 2 ESPA2 in FIG. Information to be recorded is recorded in the defect location found in the additionally recordable area 205 of data.

Corresponds to
(2) In the case of multiplexing mode: • Set the defect management process type information to “10”,
The “position information of the replacement ECC block” is a non-defect location, information to be recorded is recorded, and the information recorded here represents location information of a location that can be accurately reproduced.

“Replacement ECC block position information” means the “replacement ECC block” described above for multiplexing set in the replacement area SPA or the extended replacement area 1 ESPA1 and the extended replacement area 2 ESPA2 in FIG. The position information of the place where the same content as the information recorded in the “position information” is recorded.

  Corresponds.

In the case of recording in the “(1) alternate mode”, it is confirmed that the information recorded on the information storage medium can be read accurately immediately after the recording. However, there is a risk that the recording cannot be reproduced due to scratches or dust adhering to the information storage medium due to the user's omission. On the other hand, in the case of recording in the “(2) multiplexing mode”, even if the information storage medium is damaged due to a user's inconvenience or the like and the information cannot be read partially, it is the same as other parts. Since the information is backed up, the reliability of information reproduction is greatly improved. If the information that could not be read at this time is subjected to the replacement process of “(1) replacement mode” using the backed up information, the reliability is further improved. Therefore, after recording, the above-mentioned “(2) multiplexing mode” processing or “(1) alternate mode” processing and “(2) multiplexing mode” processing are combined to take measures against scratches and dust. There is an effect that high information reproduction reliability can be secured. As a method of describing the position information of the ECC block, there is a method of describing the ECC block address, the physical segment block address, or the data segment address in addition to the method of describing the physical sector number of the physical sector at the head position constituting the ECC block. Yes. As will be described later, in the present embodiment, an area on data in which data of one ECC block size enters is called a data segment. A physical segment block is defined as a physical unit on the information storage medium where data is recorded, and one physical segment block size and the size of an area for recording one data segment are the same.

In this embodiment, there is also a mechanism capable of recording defect position information detected in advance before the replacement process. As a result, the manufacturer of the information storage medium inspects the defect state in the user data appendable range 204 immediately before shipment, records the detected defect location in advance (before the replacement process), or provides information at the user's location. When the recording / reproducing apparatus performs the initialization process, the defect state in the additionally recordable range 204 of the user data is inspected, and the found defect location can be recorded in advance (before the replacement process). Information indicating the defect position detected in advance before the replacement process in this manner is “replacement process presence / absence information of replacement of defective block with replacement block” in the secondary defect list entry information shown in Table 14 (SLR: Status of Linear Replacement). ) And
◎ When the replacement process presence / absence information SLR to the replacement block of the defective block is “0”, the replacement process is performed on the defective ECC block specified by “position information of the replacement source ECC block”,
Reproducible information is recorded at a location specified by “position information of replacement ECC block”.

◎ When the replacement process presence / absence information SLR to the replacement block of the defective block is “1” ... The defective ECC block specified by the “position information of the replacement ECC block” is the defective block detected in advance before the replacement process Means
The column of “position information of replacement ECC block” is blank (no information is recorded).

Thus, when the defect location is known in advance, there is an effect that an optimum replacement process can be performed at high speed (and in real time) at the stage where the information recording / reproducing apparatus additionally writes user data to the write-once information storage medium. In particular, when recording video information or the like on an information storage medium, it is necessary to ensure continuity during recording, and high-speed replacement processing based on the information is important.

  If there is a defect in the user data appendable range 205, a replacement process is performed at a predetermined location in the replacement area SPA or the extended replacement area ESPA, but one secondary defect list entry ( Secondary Defect List Entry) information is added, and set information of defective ECC block position information and ECC block position information used instead is recorded in this RMD field 6. If a new defect location is found when user data additional recording is repeated within the user data additional recordable range 205, replacement processing is performed, and the number of secondary defect list entry information increases. As shown in FIG. 24B, the recording position management data RMD having the increased number of secondary defect list entry information is additionally written in the reserved area 273 in the recording position management zone RMZ, so that the defect management management information area ( The RMD field 6) can be expanded. By performing this method, the reliability of the defect management information itself can be improved for the following reasons.

(1) It is possible to record the recording position management data RMD while avoiding the defective place in the recording position management zone RMZ.... By checking (verifying) the contents of the newly added recording position management data RMD in the recording position management zone RMZ immediately after the addition, it is possible to detect an unrecordable state due to a defect. By rewriting the data RMD, the recording position management data RMD can be recorded in a form guaranteeing high reliability.

(2) Even if it becomes impossible to reproduce the past recording position management data RMD due to scratches on the surface of the information storage medium, a certain level of backup is possible. For example, the example of FIG. In this case, it is assumed that the recording position management data RMD # 2 is recorded and the information storage medium surface is damaged due to a user's mistake or the like, and the recording position management data RMD # 2 cannot be reproduced. In this case, it is possible to repair past defect management information (information in the RMD field 6) to some extent by reproducing the information of the recording position management data RMD # 1 instead.

  The size information of the RMD field 6 is recorded at the beginning of the RMD field 6, and the defect management information area (RMD field 6) can be expanded by changing the field size. Although it has already been described that each RMD field is set to 2048 size (one physical sector size), the size of the secondary defect list information (Secondary Defect List) is increased when the number of defects in the information storage medium increases and the number of replacement processes increases. Will not fit in the 2048 byte size (one physical sector size). In consideration of the situation, the RMD field 6 can be made a multiple of 2048 size (recordable across a plurality of sectors). In other words, when the “RMD field 6 size” exceeds 2048 bytes, an area for a plurality of physical sectors is allocated to the RMD field 6.

  In the secondary defect list information SDL, in addition to the secondary defect list entry information described above, “secondary defect list identification information” indicating the start position of the secondary defect list information SDL, and the secondary defect list information SDL are included. A “secondary defect list update counter (update number information)” indicating the number of times of rewriting is recorded. The data size of the entire secondary defect list information SDL can be known from “number information of secondary defect list entries”.

It has already been described that user data is logically recorded in R zone units within the user data additional recordable range 205. That is, a part of the user data additionally recordable range 205 reserved for recording user data is referred to as an R zone. This R zone is divided into two types of R zones according to the recording conditions. A type in which additional user data can be further recorded is called “Open R Zone”, and a type in which no additional user data can be added is “Complete R Zone”. Call it. It is not possible to have three or more “open R zones” within the user data appendable range 205 (that is, within the user data appendable range 205, only two “open R zones” can be set. ). Within the user data appendable range 205, any of the above two types of R zones is not set, that is, a reserved location for recording user data (as one of the above two types of R zones) It is referred to as “designated state R zone (Invisible R Zone)”. If all user data is recorded within the user data appendable range 205 and cannot be added, this “undesignated R zone” does not exist. In the RMD field 7, position information of up to the 254th R zone is recorded. The “total number of R zone information” recorded first in the RMD field 7 is the number of “invisible R zones” logically set in the user data recordable range 205. And the total number of “Open R Zones” and “Complete R Zones”. Next, the number information of the first “Open R Zone” and the number information of the second “Open R Zone” are recorded. As described above, additional user data is added. Since it is not possible to have more than 3 “open R zones” within the possible range 205, “1” or “0” is recorded here (if there is no first or second open R zone). The Next, the start position information and end position information of the first “Complete R Zone” are described as physical sector numbers. Next, start position information and end position information from the 2nd to the 254th are sequentially described by physical sector numbers.

  From the RMD field 8 onward, the 255th and subsequent start position information and end position information are sequentially described in physical sector numbers, and up to the maximum RMD field 15 (maximum 2047) according to the number of “Complete R Zones”. (To complete R zone).

  Tables 16 and 17 show other embodiments for the data structure in the recording position management data RMD shown in Tables 10 to 15.

  In the embodiments of Tables 16 and 17, up to 128 border areas BRDA can be set on one recordable information storage medium. Accordingly, start position information of up to 128 border-out BRDO is recorded in the RMD field 3 from the beginning. If the bordered area BRDA is set only halfway (128 or less), “00h” is set as the start position information of the subsequent border-out BRDO. As a result, it is possible to know how many border areas BRDA are set on the write-once information storage medium only by checking how far the start position information of the border-out BRDO is recorded in the RMD field 3.

In the embodiments of Tables 16 and 17, up to 128 extended recording position management zones RMZ can be set on one recordable information storage medium. As described above, as the extended recording position management zone RMZ 1) The extended recording position management zone RMZ set in the border-in BRDI 2) The extended recording position management zone RMZ set using the R zone
In the embodiments shown in Tables 16 and 17, the start position information (indicated by the physical sector number) and size information (occupied physical) of the extended recording position management zone RMZ are distinguished without distinguishing the two types. This is managed by recording a set of (number of sectors information) in the RMD field 3. In the embodiments of Table 16 and Table 17, information on a set of start position information (displayed by physical sector number) and size information (number information of occupied physical sectors) of the extended recording position management zone RMZ is recorded. Not limited to this, it may be recorded as a set of start position information (indicated by physical sector number) and end position information (indicated by physical sector number) of the extended recording position management zone RMZ. In the embodiments of Tables 16 and 17, the numbers of the extended recording position management zones RMZ are assigned in the order set on the write-once information storage medium. However, not limited to this, the extended recording is performed in ascending order of the physical sector numbers. The number of the location management zone RMZ can also be attached. The latest recording position management data RMD is recorded, and the designation of the recording position management zone that is currently in use (opened and RMD can be additionally written) is designated by the number of this extended recording position management zone RMZ. Therefore, the information recording / reproducing apparatus or the information reproducing apparatus knows the start position information of the recording position management zone currently in use (opened) from these information, and from which information is the latest recording position management data RMD. Identify. Even if the extended recording position management zone is distributed on the write-once information storage medium, the information recording / reproducing apparatus or the information reproducing apparatus has the latest recording position management data RMD by adopting the data structures shown in Tables 16 and 17. Can be easily identified. From this information, the start position information of the currently used (open) recording position management zone is known, and the information recording is performed by accessing the place and knowing how far the recording position management data RMD has already been recorded. The playback device or the information playback device can easily know where the latest updated recording position management data should be recorded. 2) Extended recording position management zone RMZ set using the R zone.
In this case, since one entire R zone corresponds to one extended recording position management zone RMZ as it is, a physical indicating the start position of the corresponding extended recording position management zone RMZ described in the RMD field 3 is used. The sector number matches the physical sector number indicating the start position of the corresponding R zone described in the RMD fields 4-21.

In the embodiments of Table 16 and Table 17, up to 4606 (4351 + 255) R zones can be set in one recordable information storage medium. The position information of the set R zone is recorded in the RMD fields 4-21. The start position information of each R zone is displayed as physical sector number information, and a physical sector number LRA (Last Record Address) representing the last recording position in each R zone is recorded as a pair. The order of the R zones described in the recording position management data RMD is the setting order of the R zones in the embodiments of Tables 16 and 17, but the order is not limited to the order of the physical sector numbers representing the start position information. It can also be set. If no corresponding zone R zone is set, “00h” is recorded in this field. The number information of the invisible R zone is described in the RMD field 4, but the number information of the invisible R zone is the number of invisible R zones (the area where data recording is not reserved in the data area DTA) and Total number of open R zones (R zones that have unrecorded areas that can be added later) and complete R zones (R zones that have already been completed and do not have unrecorded areas that can be added later) Indicated by In the embodiments of Tables 16 and 17, up to two open R zones that can be additionally written can be set. In this way, by setting up to two open R zones, video information and audio information that needs to be guaranteed continuous recording and continuous playback are recorded in one open R zone, and the remaining one is recorded. Depending on the type of user data to be recorded, such as recording management information for video and audio information, general information used in personal computers, etc., or file system management information in the open R zone Each zone can be recorded separately, and convenience is improved for recording and reproduction of AV information (video information and audio information). In the embodiments of Tables 16 and 17, which R zone is the open R zone is designated by the arrangement number of the R zone arranged in the RMD fields 4 to 21. That is, it is designated by the number of the R zone corresponding to the first and second open type R zones. By taking such a data structure, it becomes easy to search for the open R zone. If there is no open R zone, “00h” is recorded in this field. In this embodiment, the end position of the R zone coincides with the last recording position in the complete R zone, but the end position of the R zone and the last recording position LRA in the R zone are within the open type R zone. Is different. During the additional recording of user information in the open R zone (as a result, before the completion of the additional recording processing of the recording position management data RMD to be updated), the last recording position and the final recording that can be additionally recorded The position shifts. However, after the additional recording process of user information is completed and the additional recording process of the latest recording position management data RMD to be updated is completed, the final recording position further matches the final recording position where additional recording is possible. Accordingly, in the case where new user information is additionally written after the latest recording position management data RMD to be updated is completed, the control unit 143 in the information recording / reproducing apparatus shown in FIG. Check the number of the R zone corresponding to the open R zone described in the RMD field 4 (2) Physical indicating the last recording position in the open R zone described in the RMD fields 4 to 21 The sector number is checked to determine the final recordable position for additional recording. (3) Processing is performed in the procedure of starting additional recording from the determined final recordable position NWA for additional recording. In this way, by using the open R zone information in the RMD field 4 to determine a new additional recording start position, it becomes possible to extract a new additional recording start position easily and at high speed.

  Table 18 shows the data structure in the RMD field 1 in the embodiments of Table 16 and Table 17.

  Compared with the embodiments shown in Tables 10 to 15, the address information of the place where the recording condition adjustment is performed in the inner drive test zone DRTZ (belonging to the data lead-in area DTLDI) and the outer (data lead-out area DTLDO) Address information of the place where the recording condition adjustment was performed in the drive test zone DRTZ. These pieces of information are described with physical segment block address numbers. Further, in the embodiment of Table 18, information on the automatic recording condition adjustment method (running OPC) and the last DSV (Digital Sum Value) value at the end of recording are added.

  FIG. 32 shows an outline of the conversion procedure from the construction of the ECC block from the data frame structure in which user data of 2048 bytes is recorded, the addition of the synchronization code, and the formation of the physical sector structure to be recorded on the information storage medium Show. This conversion procedure is commonly used for any reproduction-only information storage medium, write-once information storage medium, or rewritable information storage medium. Depending on each conversion stage, it is called a data frame, a scrambled frame, a recording frame, or a recorded data field. The data frame is a place where user data is recorded. Main data including 2048 bytes, 4-byte data ID, 2-byte ID error detection code (IED), 6-byte reserved bytes RSV, 4-byte data It consists of an error detection code (EDC). First, after an IED (ID error detection code) is added to a data ID, which will be described later, a 6-byte reserved byte and a data frame are locations where user data is recorded, and main data consisting of 2048 bytes is added. After adding the error detection code (EDC), the main data is scrambled. Here, a cross-reed-Solomon error correction code (Cross Reed-Solomon Error Correction Code) is applied to the 32 scrambled data frames (scrambled frames), and ECC encoding processing is executed. This constitutes a recording frame. This recording frame includes an outer parity code (Parity of Outer-code) PO and an inner parity code (Parity of Inner-code) PI. PO and PI are error correction codes created for each ECC block composed of 32 scrambled frames. As described above, the recording frame is ETM (Eight to Twelve Modulation) modulated to convert 8 data bits into 12 channel bits. Then, a sync code (Sync Code) SYNC is added to the head every 91 bytes to form 32 physical sectors. As described in the lower right frame of FIG. 32, the present embodiment is characterized in that one error correction unit (ECC block) is configured by 32 sectors. As will be described later, the numbers from “0” to “31” in each frame in FIG. 36 or FIG. 37 indicate the numbers of the physical sectors, and a total of 32 physical sectors from “0” to “31”. It has a structure that constitutes one large ECC block. The next generation DVD is required to be able to reproduce accurate information by error correction processing even when a scratch of the same length as the current generation DVD is attached to the surface of the information storage medium. In this embodiment, the recording density is increased with the aim of increasing the capacity. As a result, in the case of the conventional 1 ECC block = 16 sectors, the length of the physical flaw that can be corrected by error correction is shorter than that of the conventional DVD. By adopting a structure in which one ECC block is composed of 32 sectors as in this embodiment, the allowable length of the surface of an information storage medium that can be corrected for errors can be increased, and compatibility and format continuity of the current DVDECC block structure can be ensured. There is an effect that can be done.

  FIG. 33 shows the structure in the data frame. One data frame is 2064 bytes composed of 172 bytes × 2 × 6 rows, and includes 2048 bytes of main data. IED is an abbreviation of ID Error Detection Code and means an error detection additional code for data ID information during reproduction. REV is an abbreviation for Reserve, which means a reserved area where future information can be set. EDC is an abbreviation for Error Detection Code and means an additional code for error detection of the entire data frame.

  FIG. 30 shows a data structure in the data ID shown in FIG. The data ID is composed of data frame information 921 and data frame number 922 information, and the data frame number indicates the physical sector number 922 of the corresponding data frame.

  The data frame information 921 is composed of the following information.

-Format type 931 ... 0b: CLV,
1b: Represents a zone configuration. Tracking method 932... 0b: Corresponds to a pit. In this embodiment, a DPD (Differential Phase Detect) method is used.
1b: Pre-groove compatible, use Push-Pull method or DPP (Differential Push-Pull) method. Recording film reflectance 933... 0b: 40% or more
1b: 40% or less ・ Recording type information 934... 0b: General data
1b: Real-time data (Audio Video data)
Area type information 935... 00b: Data area DTA
01b: System lead-in area SYLDI or data lead-in area DTLDI
10b: Data lead-out area DTLDO or system lead-out area SYLDO
Data type information 936 ... 0b: Playback-only data
1b: Rewriteable data layer number 937... 0b: Layer 0
1b: Layer 1
FIG. 34A shows an example of an initial value given to the feedback shift register when creating a scrambled frame, and FIG. 34B shows a circuit configuration of the feedback shift register for creating a scramble byte. Show. r7 (MSB) to r0 (LSB) are shifted by 8 bits and used as a scramble byte. As shown in FIG. 34A, 16 types of preset values are prepared in this embodiment. The initial preset number in FIG. 34A is equal to 4 bits (b7 (MSB) to b4 (LSB)) of the data ID. At the start of data frame scrambling, the initial values of r14 to r0 must be set to the initial preset values in the table of FIG. The same initial preset value is used for 16 consecutive data frames. Next, the initial preset values are switched, and the same switched preset values are used for 16 consecutive data frames.

  The lower 8 bits of the initial values of r7 to r0 are taken out as a scramble byte S0. Thereafter, an 8-bit shift is performed, and then a scramble byte is taken out, and such an operation is repeated 2047 times.

  FIG. 35 shows an ECC block structure in this embodiment. The ECC block is formed of 32 consecutive scrambled frames. 192 rows + 16 rows are arranged in the vertical direction, and (172 + 10) × 2 columns are arranged in the horizontal direction. B0, 0, B1, 0,... Are each 1 byte. PO and PI are error correction codes, and are outer parity and inner parity. In the present embodiment, an ECC block structure using a product code is configured. That is, the data to be recorded on the information storage medium is two-dimensionally arranged, and as additional bits for error correction, PI (Parity in) in the “row” direction and PO (Parity out) in the “column” direction It has a structure with. By configuring an ECC block structure using product codes in this way, high error correction capability by erasure correction and vertical and horizontal iterative correction processing can be guaranteed. The ECC block structure shown in FIG. 35 differs from the conventional DVD ECC block structure in that two PIs are set in the same “row”. That is, the 10-byte PI described in the center in FIG. 35 is added to the 172 bytes arranged on the left side. That is, for example, a 10-byte PI from B0,172 to B0,181 is added as a PI to the 172-byte data from B0,0 to B0,171, and the 172-byte data from B1,0 to B1,171 is added. On the other hand, a 10-byte PI from B1,172 to B1,181 is added as a PI. The 10-byte PI described at the right end of FIG. 35 is added to the 172 bytes arranged in the center on the left side. That is, for example, a 10-byte PI from B0,354 to B0,363 is added as a PI to the 172-byte data from B0,182 to B0,353.

  FIG. 36 is an explanatory diagram of the frame arrangement after scramble. A unit of (6 rows × 172 bytes) is treated as a frame after one scramble. That is, one ECC block is composed of 32 consecutive scrambled frames. Further, this system handles (block 182 bytes × 207 bytes) as a pair. If L is added to the number of each scrambled frame in the left ECC block and R is added to the number of each scrambled frame in the right ECC block, the scrambled frame is arranged as shown in FIG. Yes. That is, left and right scrambled frames are alternately present in the left block, and scrambled frames are alternately present in the right block.

  That is, the ECC block is formed from 32 frames after continuous scrambling. Each row in the left half of the odd sector is replaced with a row in the right half. 172 × 2 bytes × 192 rows is equal to 172 bytes × 12 rows × 32 scrambled frames, and becomes a data area. A 16-byte PO is added to form an outer code of RS (208, 192, 17) in each 172 × 2 column. A 10-byte PI (RS (182, 172, 11)) is added to each 208 × 2 row of the left and right blocks. PI is also added to the PO line. The numbers in the frame indicate the scrambled frame number, and the suffixes R and L mean the right half and the left half of the scrambled frame. The feature of this embodiment is that the same data frame is distributed and arranged in a plurality of small ECC blocks. Specifically, in the present embodiment, one small ECC block is composed of two small ECC blocks, and the same data frame is alternately distributed within the two small ECC blocks. In the description of FIG. 35, the 10-byte PI described in the center is added to the 172 bytes arranged on the left side, and the 10-byte PI described on the right end is the center on the left. It has already been explained that it is added to 172 bytes arranged in. That is, a left side (Left side) small ECC block is composed of 10 bytes of PI that are continuous with 172 bytes from the left end of FIG. Is configured. Correspondingly, symbols in each frame of FIG. 36 are set. For example, the meaning such as “2-R” in FIG. 36 indicates whether the data frame number or the left and right small ECC blocks belong (for example, belongs to the right side small ECC block in the second data frame). ing. As will be described later, the data in the same physical sector is also distributed and arranged alternately in the left and right small ECC blocks for each physical sector to be finally configured (the left half column in FIG. 37 is the left small ECC block ( 39 is included in the left small ECC block A) shown in FIG. 39, and the right half column is included in the right small ECC block (right small ECC block B shown in FIG. 39).

  When the same data frame is distributed and arranged in a plurality of small ECC blocks as described above, the reliability of recorded data can be improved by improving the error correction capability of data in the physical sector (FIG. 37). For example, consider a case where a track is removed during recording and the recorded data is overwritten, and data for one physical sector is destroyed. In this embodiment, error correction is performed on the corrupted data in one sector using two small ECC blocks, so that the burden of error correction in one ECC block is reduced, and error correction with better performance is guaranteed. Is done. In this embodiment, since the data ID is arranged at the head position of each sector even after the ECC block is formed, the data position at the time of access can be confirmed at high speed.

  FIG. 37 shows an explanatory diagram of the PO interleaving method. As shown in FIG. 37, the 16 parity rows are distributed one by one. That is, 16 parity rows are arranged one by one for every two recording frames. Therefore, a recording frame consisting of 12 lines is 12 lines + 1 line. After this row interleaving is performed, 13 rows × 182 bytes are referred to as a recording frame. Therefore, the ECC block after row interleaving is composed of 32 recording frames. In one recording, there are six rows of blocks on the right and left sides as described in FIG. The PO is arranged in a different row between the left block (182 × 208 bytes) and the right block (182 × 208 bytes). In FIG. 37, one complete ECC block is shown. However, during actual data reproduction, such ECC blocks continuously arrive at the error correction processing unit. In order to improve the correction capability of such error correction processing, an interleaving method as shown in FIG. 37 is adopted.

  The relationship from the structure in one data frame shown in FIG. 33 to the PO interleaving method shown in FIG. 37 will be described in detail with reference to FIG. In FIG. 39, the upper part of the ECC block structure diagram after PO interleaving shown in FIG. 37 is enlarged, and the location of the data ID, IED, RSV, and EDC shown in FIG. The connection of the conversion from to 37 can be understood at a glance. In FIG. 39, “0-L”, “0-R”, “1-R”, “1-L” are “0-L”, “0-R”, “1-R”, “1-R” in FIG. 1-L ″. "0-L" and "1-L" mean the data after scrambled only the main data for the left half of FIG. 33, that is, the 172 bytes and 6 rows on the left side from the center line. To do. Similarly, “0-R” and “1-R” are obtained by scrambling only the main data with respect to the right half of FIG. 33, that is, a group consisting of 172 bytes and 6 rows on the right side from the center line. Means data. Therefore, as apparent from FIG. 33, the data ID, IED, and RSV are arranged in order from the first to the 12th byte of the first row (0th row) of “0-L” or “1-L”. In FIG. 39, the left side from the center line constitutes a small ECC block A on the left side, and the right side from the center line constitutes a small ECC block B on the right side. Therefore, as can be seen from FIG. 39, data ID # 1, data ID # 2, IED # 0, IED # 2, RSV # 0, and RSV # 2 included in “0-L” and “2-L” are on the left side. Are included in the small ECC block A. In FIG. 36, “0-L” and “2-L” are arranged on the left side, and “0-R” and “2-R” are arranged on the right side, whereas “1-R” and “1” The arrangement of -L "is reversed left and right, and" 1-L "is arranged on the right side and" 1-R "is arranged on the left side. Since data ID # 1, IED # 1, and RSV # 1 are arranged from the first to the 12th byte of the first row in “1-L”, the left and right arrangements are reversed, so that FIG. 39 shows. Thus, the data ID # 1, IED # 1, and RSV # 1 included in “1-L” are configured in the small ECC block B on the right side. In this embodiment, the combination of “0-L” and “0-R” in FIG. 39 is the “0th recording frame”, and the combination of “1-L” and “1-R” is the “first recording frame”. Called “frame”. The boundaries between the recording frames are shown in bold in FIG. As can be seen from FIG. 39, a data ID is arranged at the beginning of each recording frame, and PO and PI-L are arranged at the end of each recording frame. As shown in FIG. 39, the small ECC blocks including the data ID are different between the odd and even recording frames, and the data ID, IED, and RSV are changed to the left and right small ECC blocks A and B according to the continuation of the recording frame. There is a big feature in the place where it is arranged alternately. There is a limit to the error correction capability within one small ECC block, and error correction is impossible for random errors exceeding a specific number or burst errors exceeding a specific length. As described above, the data ID, IED, and RSV are alternately arranged in the left and right small ECC blocks A and B, so that the reproduction reliability of the data ID can be improved. That is, even if defects on the information storage medium frequently occur and error correction of one of the small ECC blocks is impossible, and the data ID belonging to that block cannot be decoded, the data ID, IED, and RSV are on the left side. Since the small ECC blocks A and B on the right side are alternately arranged, error correction is possible in the other small ECC block, and the remaining data ID can be decoded. Since the address information in the data ID has continuity, it is possible to interpolate the information of the data ID that cannot be decoded using the information of the data ID that can be decoded. As a result, the reliability of access can be improved by the embodiment shown in FIG. The numbers enclosed in parentheses on the left side of FIG. 39 indicate the row numbers in the ECC block after PO interleaving. When recording on the information storage medium, the recording is sequentially performed from left to right in the order of row numbers. In FIG. 39, since the data ID intervals included in each recording frame are always arranged at a constant interval, the data ID position searchability is improved.

  The physical sector structure is shown in FIG. FIG. 38A shows an even-numbered physical sector structure, and FIG. 38B shows an odd-numbered data structure. In FIG. 38, both the even recorded data field (Oven Recorded data field) and the odd recorded data field (Odd Recorded data field) are the last two sync frames (that is, the last sync code is SY3 and the immediately following sync data and The information of the outer parity PO shown in FIG. 37 is inserted into the sync data area in the portion where the sync code is SY1 and the sync data immediately after that.

  A part of the left PO shown in FIG. 36 is inserted into the last two sync frame locations in the even recording data area, and the right side shown in FIG. 36 is inserted into the last two sync frame locations in the odd recording data area. Part of PO is inserted. As shown in FIG. 36, one ECC block is composed of left and right small ECC blocks, and is alternately different for each sector, which belongs to a PO group (PO belonging to the left small ECC block or right small left ECC block). PO?) Data is inserted. Both the even-numbered physical sector structure shown in FIG. 38 (a) and the odd-numbered data structure shown in FIG. 38 (b) are divided into two at the center line, and the “24 + 1092 + 24 + 1092 channel bits” on the left are shown in FIG. Are included in the small ECC block on the left side (Left side) shown in FIG. 35, and “24 + 1092 + 24 + 1092 channel bits” on the right side are included in the small ECC block on the right side (Right side) shown in FIG. When the physical sector structure shown in FIG. 38 is recorded on the information storage medium, it is recorded serially for each column. Therefore, for example, when the channel bit data of the even-numbered physical sector structure shown in FIG. 38A is recorded on the information storage medium, the data of 2232 channel bits to be recorded first is the left side (Left side) small. Data of 2232 channel bits to be recorded next included in the ECC block is included in the small ECC block on the right side (Right side). Further, 2232 channel bit data to be recorded next is included in a small ECC block on the left side (Left side). On the other hand, when the channel bit data of the odd-numbered data structure shown in FIG. 38B is recorded on the information storage medium, the data of 2232 channel bits to be recorded first is the small ECC on the right side (Right side). Data of 2232 channel bits to be recorded next included in the block is included in the small ECC block on the left side (Left side). Further, 2232 channel bit data to be recorded next is included in the small ECC block on the right side (Right side). As described above, this embodiment is characterized in that the same physical sector is alternately assigned to two small ECC blocks every 2232 channel bits. In other words, the data contained in the right side (Right side) small ECC block and the data contained in the left side (Left side) small ECC block are alternately distributed every 2232 channel bits. A physical sector is formed and recorded on the information storage medium. As a result, there is an effect that a structure strong against burst errors can be provided. For example, consider a state of a burst error in which a long flaw in the circumferential direction of the information storage medium makes it impossible to read data exceeding 172 bytes. In this case, burst errors exceeding 172 bytes are distributed and arranged in two small ECC blocks, so that the burden of error correction in one ECC block is reduced and error correction with better performance is guaranteed.

As shown in FIG. 38, there is a feature in that the data structure in the physical sector is different depending on whether the physical sector number of the physical sector constituting one ECC block is an even number or an odd number. In other words, (1) The small ECC block (right side or left side) to which the first 2232 channel bit data of the physical sector belongs is different. (2) Different PO group data is inserted in each sector. Even after the ECC block is configured, the structure in which the data ID is arranged at the head position of all the physical sectors is guaranteed, so that the data position at the time of access can be confirmed at high speed. Further, the structure using the PO insertion method as shown in FIG. 37 is simpler than the case where POs belonging to different small ECC blocks are mixedly inserted in the same physical sector, and each sector after error correction processing in the information reproducing apparatus is simplified. Information can be easily extracted every time, and the assembly process of ECC block data in the information recording / reproducing apparatus can be simplified.

As a method for specifically realizing the above contents, the PO interleave / insertion position is different on the left and right. The portion indicated by the narrow double line in FIG. 37 or the portion indicated by the narrow double line and the diagonal line indicates the PO interleave / insertion position. In the physical sector number, PO is inserted at the end on the right side. By adopting this structure, the data ID is arranged at the head position of the physical sector even after the ECC block is configured, so that the data position at the time of access can be confirmed at a high speed. Sync code) Table 20 shows an embodiment of specific pattern contents from “SY0” to “SY3”.

  Corresponding to the modulation rule of this embodiment (details will be described later), it has three states (State) from State 0 to State 2. Four types of sync codes from SY0 to SY3 are set, and are selected from the left and right groups in Table 20 according to each state. In the current DVD standard, 8/16 modulation (converting 8 bits to 16 channel bits) RLL (2, 10) (Run Length Limited: d = 2, k = 10: “0” is a continuous range The minimum value is 2 and the maximum value is 10). Four states from State 1 to State 4 and 8 types of sync codes from SY0 to SY7 are set for modulation. In comparison with this, the type of synchronization code (sync code) is reduced in this embodiment. In the information recording / reproducing apparatus or the information reproducing apparatus, the type of the sync code is identified by the pattern matching method when reproducing the information from the information storage medium. By greatly reducing the types of sync codes as in this embodiment, the number of target patterns required for matching is reduced, the processing required for pattern matching is simplified and the processing efficiency is improved, and the recognition speed is improved. It becomes possible to make it.

  In Table 20, a bit (channel bit) indicated by “#” represents a DSV (Digital Sum Value) control bit. The DSV control bit is determined so as to suppress the DC component (the value of DSV approaches “0”) by a DSV controller (DSV controller) as described later. A feature of this embodiment is that the polarity code channel bit “#” is included in the synchronization code. Including the frame data area (1092 channel bit area in FIG. 38) on both sides sandwiching the sync code (sync code), the value of “#” is set so that the DSV value approaches “0” macroscopically. 1 "or" 0 "can be selected, and there is an effect that DSV control with a macroscopic view becomes possible.

  As shown in Table 20, the sync code in the present embodiment is composed of the following parts.

(1) Synchronous position detection code part A common code pattern is formed in all sync codes, and a fixed code area is formed. By detecting this code, the arrangement position of the sync code can be detected. Specifically, it means the last 18 channel bits “010000 000000 00101” in each sync code in Table 20.

(2) Conversion table selection code part at the time of modulation A code that forms a part of the variable code area and changes corresponding to the State number at the time of modulation. This corresponds to the first one channel bit in Table 20. That is, when either State 1 or State 2 is selected, the first one channel bit is “0” in any code from SY0 to SY3. When State 0 is selected, the first one channel bit of the sync code is “1”. It has become. However, as an exception, the first one channel bit of SY3 in State0 is “0”.

(3) Sync frame position identification code portion A code for identifying each type from SY0 to SY3 in the sync code constitutes a part of the variable code area. The first to sixth channel bit portions in each sync code in Table 20 correspond to this. As will be described later, the relative position in the same sector can be detected from the connection pattern of three sync codes detected successively.

(4) DC suppression polarity inversion code portion The channel bit at the “#” position in Table 20 corresponds to the channel bit string including the frame data before and after the bit is inverted or non-inverted as described above. It works so that the DSV value approaches “0”.

  In the present embodiment, 8/12 modulation (ETM: Eight to Twelve Modulation) or RLL (1, 10) is adopted as a modulation method. In other words, 8 bits are converted to 12 channel bits during modulation, and the range in which the converted “0” continues is set so that the minimum value (d value) is 1 and the maximum value (k value) is 10. ing. In this embodiment, by setting d = 1, it is possible to achieve higher density than before, but it is difficult to obtain a sufficiently large reproduction signal amplitude at the closest mark.

  Therefore, as shown in FIG. 9, the information recording / reproducing apparatus of the present embodiment has a PR equalization circuit 130 and a Viterbi decoder 156, and uses a PRML (Partial Response Maximum Likelihood) technique to achieve very stable signal reproduction. Is possible. Since k = 10 is set, 11 or more “0” s do not continue in the modulated general channel bit data. Using this modulation rule, the synchronization position detecting code section has a pattern that does not appear in the modulated general channel bit data. That is, as shown in Table 20, 12 (= k + 2) “0” s are continued in the synchronization position detection code part. The information recording / reproducing apparatus or the information reproducing apparatus finds this portion and detects the position of the synchronization position detecting code section. In addition, if “0” continues continuously for too long, a bit shift error is likely to occur. Therefore, in order to alleviate the adverse effect, a pattern with a small number of consecutive “0” s is placed immediately after that in the synchronization position detection code section. Yes. In this embodiment, since d = 1, it is possible to set “101” as the corresponding pattern. However, as described above, it is difficult to obtain a sufficiently large reproduction signal amplitude at “101” (the closest pattern). Therefore, “1001” is arranged instead and the pattern of the synchronization position detection code portion as shown in Table 20 is used.

  In this embodiment, as shown in Table 20, the rear 18 channel bits in the sync code are independently (1) the synchronization position detection code section, and the front 6 channel bits are used. (2) Conversion at the time of modulation The table selection code section, (3) sync frame position identification code section, and (4) DC suppression polarity inversion code section are also used. (1) The synchronization position detection code part is made independent in the sync code, so that independent detection is facilitated and the synchronization position detection accuracy is improved, and the code parts (2) to (4) are also used in 6 channel bits. As a result, the data size (channel bit size) of the entire sync code is reduced, and the occupancy rate of the sync data is increased, thereby effectively improving the data efficiency.

  Of the four types of sync codes shown in Table 20, only SY0 is arranged at the first sync frame position in the sector as shown in FIG. As an effect, the head position in the sector can be determined immediately by simply detecting SY0, and the process of extracting the head position in the sector is greatly simplified.

  A combination pattern of three consecutive sync codes has a feature that they are all different within the same sector.

  The reference code pattern contents recorded in the reference code recording zone RCZ shown in FIG. 23 will be described in detail. The current DVD employs an “8/16 modulation” method for converting 8-bit data into 16 channel bits as a modulation method, and the pattern of a reference code as a channel bit string recorded on the information storage medium after modulation is “0010000001000000100100100010000001”. A repeating pattern is used. In contrast, in this embodiment, as shown in Tables 5 to 7, ETM modulation is used to modulate 8-bit data into 12 channel bits, RLL (1, 10) run-length restriction is performed, and data lead-in is performed. The PRML method is adopted for signal reproduction from the area DTLDI, the data area DTA, the data lead-out area DTLDO, and the middle area MDA. Therefore, it is necessary to set a reference code pattern optimal for the modulation rule and PRML detection. According to the run length constraint of RLL (1, 10), the minimum value in which “0” continues is “d = 1” and becomes a repetitive pattern of “10101010”. If the distance from the code “1” or “0” to the next adjacent code is “T”, the distance between adjacent “1” s in the pattern is “2T”. In the present embodiment, in order to increase the density of the information storage medium, the reproduction signal from the “2T” repetitive pattern (“10101010”) recorded on the information storage medium as described above is the objective lens (FIG. 9) in the optical head. The modulation degree (signal amplitude) can hardly be obtained because it is in the vicinity of the cutoff frequency of the MTF (Modulation Transfer Fuction) characteristic of the information recording / reproducing unit 141. Therefore, a repetitive pattern of “2T” (“10101010”) as a reproduction signal used for circuit adjustment of the information reproducing apparatus or information recording / reproducing apparatus (for example, initial optimization of each tap coefficient performed in the tap controller 332 in FIG. 13). ), The influence of noise is large and the stabilization is poor. Therefore, it is desirable to perform circuit adjustment using a “3T” pattern having the next highest density for a modulated signal performed in accordance with the run length constraint of RLL (1, 10). When considering the DSV (Digital Sum Value) value of the playback signal, the absolute value of the DC (direct current) value is proportional to the number of consecutive “0” s immediately after “1” until the next “1”. The value increases and is added to the previous DSV value. The polarity of the DC value to be added is inverted every time “1” comes. Accordingly, as a method of setting the DSV value to “0” where a channel bit string having a continuous reference code continues, the ETM modulation is set so that the DSV value becomes “0” in 12 channel bit strings after ETM modulation. The number of occurrences of “1” appearing in 12 channel bit strings after modulation is an odd number, and the DC component generated in one set of reference code cells consisting of 12 channel bits is the reference code of 12 channel bits consisting of the next set. The degree of freedom in designing the reference code pattern is increased when the DC component generated in the cell is canceled. Therefore, in this embodiment, the number of “1” appearing in the reference code cell composed of 12 channel bit strings after ETM modulation is set to an odd number. In the present embodiment, a mark edge recording method is adopted in which “1” coincides with the boundary position of a recording mark or embossed pit for high density. For example, when a “3T” repetitive pattern (“100100100100100100100”) continues, the length of the recording mark or emboss pit and the length of the space between them may be slightly different depending on the recording conditions or the master recording conditions. When the PRML detection method is used, the level value of the reproduced signal is very important, and even when the length of the recording mark or emboss pit and the length of the space between them are slightly different as described above, the signal is stable and accurate. In order to be able to detect, it is necessary to correct the slight difference in a circuit. Therefore, as a reference code for adjusting the circuit constant, the accuracy of the adjustment of the circuit constant is improved when there is a space of “3T” length as in the case of the recording mark or emboss pit of “3T” length. . Therefore, when a pattern “1001001” is included therein as a reference code pattern in this embodiment, a recording mark or emboss pit and space having a length of “3T” are always arranged. Further, not only a pattern with a high density (“1001001”) but also a pattern with a low density is necessary for circuit adjustment. Therefore, in the 12 channel bit strings after ETM modulation, a state in which the density is sparse (a pattern in which “0” continuously occurs frequently) is generated in a portion excluding the pattern “1001001”, and “1”. In consideration of setting an odd number of occurrences of the reference code pattern, the optimum condition is that the reference code pattern repeats "100100100000" as shown in FIG. Although the channel bit pattern after modulation is not shown in the figure, the data word before modulation needs to be set to “A4h” when the modulation table defined in the H format of this embodiment is used. The data “A4h” (hexadecimal representation) corresponds to the data symbol “164” (decimal representation).

  A specific method of creating data in accordance with the data conversion rule will be described below. First, the data symbol “164” (= “0A4h”) is set in the main data “D0 to D2047” in the data frame structure described above. Next, data frame 1 to data frame 15 are pre-scrambled with initial preset number “0Eh”, and data frame 16 to data frame 31 are pre-scrambled with initial preset number “0Fh”. Keep it. If pre-scramble is applied beforehand, it means that when scrambled according to the above data conversion rule, it is double scrambled, and the data symbol “164” (returns to the original pattern when double scrambled) ( = “0A4h”) appears as it is. Since DSV control cannot be performed if all the reference codes consisting of 32 physical sectors are pre-scrambled, pre-scramble is not applied only to data frame 0. When the scramble is applied and then modulated, the pattern shown in FIG. 47 is recorded on the information storage medium.

  A comparison of data recording formats (formats) for various information storage media in the present embodiment will be described with reference to FIG. FIG. 48A shows a data recording format in a conventional read-only information storage medium DVD-ROM, a conventional write-once information storage medium DVD-R, and a conventional DVD-RW, and FIG. 48B shows this embodiment. 48 (c) shows the data recording format of the write-once information storage medium in this embodiment, and FIG. 48 (d) shows the data recording format of the rewritable information storage medium. Yes. For comparison, the sizes of the ECC blocks 411 to 418 are the same, but the conventional read-only information storage medium DVD-ROM and the conventional write-once information storage medium DVD- shown in FIG. In R and the conventional DVD-RW, one ECC block is composed of 16 physical sectors, whereas in this embodiment shown in FIGS. 48B to 48D, one ECC is composed of 32 physical sectors. The place making up the block is different. In the present embodiment, as shown in FIGS. 48B to 48D, the present embodiment is provided where guard areas 442 to 448 having the same length as the sync frame length 433 are provided between the ECC blocks # 1411 to # 8418. There are features of form. In the conventional read-only information storage medium DVD-ROM, ECC blocks # 1411 to # 8418 are continuously recorded as shown in FIG. When attempting to ensure compatibility of the conventional read-only information storage medium DVD-R and the conventional DVD-RW with the conventional read-only information storage medium DVD-ROM and the data recording format (format), Restricted Overwrite When the additional writing or rewriting process called ")" is performed, there is a problem that a part of the ECC block is destroyed by overwriting, and the data reliability at the time of reproduction is greatly impaired. On the other hand, when the guard areas 442 to 448 are arranged between the data fields (ECC blocks) as in the present embodiment, the writing location is limited to the guard areas 442 to 448 to prevent data destruction of the data fields (ECC blocks). There is an effect that can be done. As shown in FIG. 48, the lengths of the guard areas 442 to 448 are the same as the sync frame length 433, which is one sync frame size, as described below. As shown in FIG. 38, sync codes (sync codes) are arranged at a constant sync frame length of 433 intervals called 1116 channel bits, and the sync code position detection unit 145 shown in FIG. The sync code position is extracted. In this embodiment, by adjusting the sync frame length 433 to the length of the guard area 442 to 448, the sync frame interval is kept unchanged even when the guard area 442 to 448 is straddled during playback. There is an effect to make it easy.

Furthermore,
(1) Improve the detection accuracy of sync code position detection by matching the appearance frequency of the sync code even in a place across the guard areas 442 to 448. (2) Discriminating the position in the physical sector including the guard areas 442 to 448. In the present embodiment, a synchronization code (sync data) is arranged in the guard area in order to facilitate the above. Specifically, as shown in FIG. 50, a postamble field 481 is formed at the start position of each guard area 442 to 468, and the sync code number “1” shown in Table 20 is formed in the postamble area 481. "Synchronization code" SY1 ". As can be seen from FIG. 38, the combinations of the sync code numbers of three consecutive sync codes in the physical sector are different at all locations. Further, the combinations of sync code numbers of three consecutive sync codes taking into account sync code numbers “1” in the guard areas 442 to 448 are also different at all locations. Accordingly, it is possible to determine not only the position information in the physical sector but also the position in the physical sector including the location of the guard area by combining sync code numbers of three consecutive synchronization codes in an arbitrary area.

  FIG. 50 shows a detailed structure in the guard areas 441 to 448 shown in FIG. The structure in the physical sector is composed of a combination of the sync code 431 and the sync data 432, but the guard areas 441 to 448 are similarly composed of a combination of the sync code 433 and the sync data 434, and the sync in the guard area # 3443. The feature of the present embodiment is that data modulated in accordance with the same modulation rule as the sync data 432 in the sector is also arranged in the data 434 area. An area in one ECC block # 2412 composed of 32 physical sectors shown in FIG. 35 is called a data field 470 in the present invention.

  50, VFO (Variable Frequency Oscillator) areas 471 and 472 are used for synchronizing the reference clock of the information reproducing apparatus or information recording / reproducing apparatus when reproducing the data area 470. As data contents recorded in the areas 471 and 472, data before modulation in a common modulation rule described later is “7Eh” continuously repeated, and a channel bit pattern actually recorded after modulation is “010001 000100”. This is a repetitive pattern (a pattern in which “0” is repeated three times in succession). In order to obtain this pattern, the first byte of the VFO areas 471 and 472 needs to be set to the state 2 state in the modulation.

  The pre-sync areas 477 and 478 represent the boundary positions between the VFO areas 471 and 472 and the data area 470, and the recording channel bit pattern after modulation is “100,000, 100,000” (a pattern in which “0” is repeated five times in succession). It has become. The information reproducing apparatus or information recording / reproducing apparatus detects the pattern change position of the repetitive pattern “100,000,000,000” in the presync areas 477, 478 from the repetitive pattern, “010001 000100”, in the VFO areas 471, 472, and the data area 470. Recognize that

  The postamble area 481 indicates the end position of the data area 470 and the start position of the guard area 443. As described above, the pattern in the postamble area 481 matches the pattern “SY1” in the synchronization code (SYNC Code) shown in Table 20.

  The extra area 482 is an area used for copy control and unauthorized copy prevention. Especially when not used for copy control or unauthorized copy prevention, all channel bits are set to “0”.

  In the buffer area, the same data before modulation as the VFO areas 471 and 472 is continuously repeated “7Eh”, and the channel bit pattern actually recorded after the modulation is a repeated pattern of “010001 000100” (three consecutive “0” s). Pattern). In order to obtain this pattern, the first byte of the VFO areas 471 and 472 needs to be set to the state 2 state in the modulation.

  As shown in FIG. 50, the postamble area 481 in which the pattern “SY1” is recorded corresponds to the sync code area 433, and the area immediately after the extra area 482 to the presync area 478 corresponds to the sync data area 434. . An area extending from the VFO area 471 to the buffer area 475 (that is, the data area 470 and an area including a part of the guard area before and after the data area 470) is called a data segment 490 in the present invention, and shows contents different from a “physical segment” described later. ing. The data size of each data shown in FIG. 50 is expressed by the number of bytes of data before modulation.

  The present embodiment is not limited to the structure shown in FIG. 50, and the following method may be employed as another embodiment. That is, instead of arranging the presync area 477 at the boundary between the VOF area 471 and the data area 470, the presync area 477 is arranged in the middle of the VOF areas 471 and 472 in FIG. In this other embodiment, the distance between the sync code of “SY0” arranged at the head position of the data block 470 and the presync area 477 is separated to obtain a large distance correlation, and the presync area 477 is set as a temporary sync. It is used as distance correlation information of the real sync position (although it is different from other sync distances). If the real sync cannot be detected, the sync is inserted at a position where the real sync generated from the temporary sync will be detected. Thus, another embodiment is characterized in that the pre-sync region 477 is somewhat distant from the real sync (“SY0”). If the presync area 477 is arranged at the beginning of the VFO areas 471 and 472, the presync function is weakened because the PLL of the read clock is not locked. Therefore, it is desirable to arrange the presync area 477 at an intermediate position between the VFO areas 471 and 472.

  In the present invention, address information in a recordable (rewritable or recordable) information storage medium is recorded in advance using wobble modulation. The feature of the present embodiment is that address information is recorded in advance on an information storage medium by using ± 90 degrees (180 degrees) phase modulation as a wobble modulation system and employing an NRZ (Non Returen to Zero) method. is there. A specific description will be given with reference to FIG. In the present embodiment, with respect to address information, one address bit (also referred to as an address symbol) area 511 is expressed by a 4-wobble period, and the frequency, amplitude, and phase are consistent throughout the one address bit area 511. When the same value continues as the address bit value, the same phase continues at the boundary part of each address bit area 511 (the part marked with “triangle” in FIG. 51), and the address bit is inverted. Inversion of the wobble pattern (180 degree phase shift) occurs. In the wobble signal detector 135 of the information recording / reproducing apparatus shown in FIG. 9, the boundary position of the address bit area 511 (the place marked with “triangle” in FIG. 51) and the slot position 412 which is the boundary position of one wobble cycle. Are detected at the same time. Although not shown in the wobble signal detection unit 135, a PLL (Phase Lock Loop) circuit is built in, and the PLL is applied in synchronization with both the boundary position of the address bit area 511 and the slot position 412. If the boundary position or the slot position 412 of the address bit area 511 is shifted, the wobble signal detection unit 135 is out of synchronization and cannot accurately reproduce (read) the wobble signal. The interval between adjacent slot positions 412 is referred to as a slot interval 513. The shorter the slot interval 513, the easier the PLL circuit can be synchronized, and the wobble signal can be stably reproduced (decoding of information contents). As is apparent from FIG. 51, when a phase modulation method of 180 degrees shifted to 180 degrees or 0 degrees is adopted, this slot interval 513 coincides with one wobble period. The AM (Amplitude Modulation) method that changes the wobble amplitude as a wobble modulation method is susceptible to dust and scratches attached to the surface of the information storage medium. However, in the above phase modulation, a change in phase is detected instead of a signal amplitude. It is relatively insensitive to dust and scratches on the surface of information storage media. In the FSK (Frequency Shift Keying) method that changes the frequency as another modulation method, the slot interval 513 is long with respect to the wobble period, and the PLL circuit is relatively difficult to synchronize. Therefore, recording address information by wobble phase modulation as in this embodiment has the effect that the slot interval is narrow and the synchronization of the wobble signal is easy to achieve.

  As shown in FIG. 51, binary data of “1” or “0” is allocated to each address bit area 511. FIG. 52 shows a bit allocation method in this embodiment. As shown on the left side of FIG. 52, the wobble pattern that first meanders from the start position of one wobble to the outer peripheral side is called NPW (Normal Phase Wobble), and data “0” is assigned. As shown on the right side, a wobble pattern that first meanders from the start position of one wobble to the inner circumference side is called IPW (Invert Phase Wobble), and data “1” is assigned.

  As shown in FIGS. 6B and 6C, when the width Wg of the pregroove area 11 is made larger than the width Wl of the land area 12, the detection signal level of the wobble detection signal is lowered and the C / N ratio is lowered. Problem occurs. On the other hand, the present embodiment is characterized in that the wobble signal detection is stabilized by expanding the non-modulation area more than the modulation area.

  The wobble address format in the H format of this embodiment will be described with reference to FIG. As shown in FIG. 73 (b), in the H format of this embodiment, one physical segment block is composed of seven physical segments 550 to 556. Each physical segment 550 to 557 is composed of 17 wobble data units 560 to 576 as shown in FIG. 73 (c). Further, each of the wobble data units 560 to 576 includes a wobble sync area 580 or a non-modulation area 590 in which a modulation area constituting any one of the modulation start marks 581 and 582 and the wobble address areas 586 and 587 and an NPW that is all continuous exists. , 591. FIG. 53 illustrates the abundance ratio between the modulation area and the non-modulation area in each wobble data unit. In any of FIGS. 53A to 53D, a modulation area 598 is constituted by 16 wobbles and a non-modulation area 593 is constituted by 68 wobbles in the wobble data unit. The present embodiment is characterized in that the non-modulation area 593 is set wider than the modulation area 598. By widening the non-modulation area 593, it is possible to stably synchronize the PLL circuit of the wobble detection signal, the write clock, or the reproduction clock using the non-modulation area 593. In order to achieve stable synchronization, it is desirable that the non-modulation region 593 is at least twice as wide as the modulation region 598. As described above, in this embodiment, 16 wobbles are allocated to the modulation area 598 and 68 wobbles are allocated to the non-modulation area 593 as shown in FIG. Yes. Further, all of the non-modulation areas 590, 591 and 593 are NPW, and the wobbles in the non-modulation areas are always in the same pattern. In this embodiment, the non-modulation areas 590, 591, and 593 are wider than the modulation area 598. Therefore, the information reproduction apparatus or information recording / reproduction apparatus can easily find the non-modulation areas 590, 591, and 593. Further, it is possible to easily synchronize the wobble clock, the reproduction clock for recording data, and the recording clock using the non-modulation area 593.

  On the other hand, as shown in FIG. 53, IPW and NPW are mixed in the modulation region 598. Therefore, if the synchronization of the PLL circuit is attempted in the modulation region 598, there is a risk that the synchronization PLL is disturbed at the boundary position between the IPW and the NPW. On the other hand, in the non-modulation area 593, since NPW always continues 68 wobbles, stable synchronization of the PLL circuit can be performed in this area.

  As a result, synchronization of the PLL circuit is performed in the non-modulation areas 590, 591, and 593 where the occupancy is high and only NPW exists, so that the synchronization of the wobble clock or the recording data reproduction clock and the recording clock can be stably performed. In addition, since the synchronization is stabilized, the wobble signal in the modulation region can be detected with high accuracy.

A recording format of address information using wobble modulation in the H format of the write-once information storage medium of the present invention will be described. The address information setting method using wobble modulation in this embodiment has a great feature in that “allocation is performed in units of sync frame length 433” shown in FIG. As shown in FIG. 38, one sector is composed of 26 sync frames, and as can be seen from FIG. 32, one ECC block is composed of 32 physical sectors. Therefore, one ECC block is composed of 26 × 32 = 832 sync frames. . As shown in FIG. 48, the length of the guard areas 442 to 468 existing between the ECC blocks 411 to 418 is equal to one sync frame length 433. Therefore, one guard area 462 and one ECC block 411 are added. The length is composed of 832 + 1 = 833 sync frames. Where
833 = 7 × 17 × 7
Because it can be factored into a factor, it has a structural arrangement that takes advantage of this feature. That is, a data segment 531 is defined as a basic unit of rewritable data in an area equal to the length of the area obtained by adding one guard area and one ECC block (the structure in the data segment 490 shown in FIG. 50). The read-only information storage medium, the rewritable information storage medium, and the write-once information storage medium are all the same), and an area having the same length as the physical length of one data segment 490 is “ The address information is recorded in advance in the form of wobble modulation for each physical segment. The boundary position of the data segment 490 and the boundary position of the physical segment do not coincide with each other and are shifted by an amount described later. Further, each physical segment is divided into 17 wobble data units (WDUs). From the above equation, it can be seen that seven sync frames are allocated to the length of one wobble data unit. In this way, a physical segment is composed of 17 wobble data units, and by matching the 7 physical segment length to the data segment length, a sync frame boundary is secured in a range across the guard areas 442 to 468, and sync code detection is facilitated. Yes.

  Each wobble data unit # 0560 to # 11571 is composed of a modulation area 598 for 16 wobbles and non-modulation areas 592 and 593 for 68 wobbles as shown in FIG. The present embodiment is greatly characterized in that the occupation ratio of the non-modulation areas 592 and 593 to the modulation area is greatly increased. Since the groove area or land area is always wobbled at a constant frequency in the non-modulated areas 592 and 593, the unmodulated areas 592 and 593 are used to perform PLL (Phase Locked Loop) and recorded on the information storage medium. It is possible to stably extract (generate) a reference clock for reproducing a recording mark or a recording reference clock used for newly recording. As described above, in this embodiment, by greatly increasing the occupation ratio of the non-modulation areas 592 and 593 to the modulation area 598, the accuracy of extraction (generation) of the reference clock for reproduction or extraction (generation) of the reference clock for recording can be improved. The extraction (generation) stability can be greatly improved. In other words, when phase modulation with wobble is performed, a phenomenon that the detection signal waveform amplitude after shaping becomes small before and after the phase change position appears when the reproduction signal is passed through a bandpass filter for waveform shaping. Therefore, if the frequency of phase change points due to phase modulation increases, the waveform amplitude fluctuation increases and the above clock extraction accuracy decreases. Conversely, if the frequency of phase change points in the modulation region is low, bit shift when detecting wobble address information This causes a problem that it is likely to occur. Therefore, in this embodiment, there is an effect of improving the clock extraction accuracy by forming a modulation region and a non-modulation region by phase modulation and increasing the occupation rate of the non-modulation region. In this embodiment, the switching position between the modulation region and the non-modulation region can be predicted in advance. Therefore, for the above clock extraction, a signal in only the non-modulation region is detected by applying a gate to the non-modulation region, and the detection signal is used to detect the above-mentioned signal. Clock extraction can be performed. In particular, when the recording layer 3-2 is composed of an organic dye recording material using the recording principle according to the present embodiment, “3-2) Basic features common to the organic dye film in the present embodiment”. 3-2-D] When the pre-groove shape / dimension described in “Basic characteristics regarding pre-groove shape / dimension in this embodiment” is used, a wobble signal is relatively difficult to obtain. In this situation, the reliability of wobble signal detection is improved by greatly increasing the occupation ratio of the non-modulation areas 590 and 591 to the modulation area as described above.

  When moving from the non-modulation areas 592 and 593 to the modulation area 598, an IPW area as a modulation start mark is set using 4 wobbles or 6 wobbles. In the wobble data portion shown in FIGS. The wobble address area (address bits # 2 to # 0) subjected to wobble modulation immediately after the detection of the IPW area as the modulation start mark is arranged. 53A and 53B show the contents in wobble data unit # 0560 corresponding to the wobble sync area 580 shown in FIG. 54C described later, and FIGS. 53C and 53D show the contents in FIG. The contents of the wobble data unit corresponding to the wobble data part from the segment information 727 to the CRC code 726 of c) are shown. 53A and 53C show the inside of a wobble data unit corresponding to a primary position 701 of a modulation area described later, and FIGS. 53B and 53D show the secondary arrangement of the modulation area. The inside of the wobble data unit corresponding to the location (Secondary position) 702 is shown. As shown in FIGS. 53A and 53B, in the wobble sync area 580, 6 wobbles are assigned to the IPW area, and 4 wobbles are assigned to the NPW area surrounded by the IPW area, as shown in FIGS. 53C and 53D. In the wobble data section, 4 wobbles are allocated to the IPW area and all the address bit areas # 2 to # 0.

  FIG. 54 shows an embodiment relating to the data structure in the wobble address information in the write-once information storage medium. For comparison, FIG. 54A shows the data structure in the wobble address information of the rewritable information storage medium. 54 (b) and 54 (c) show two embodiments concerning the data structure in the wobble address information in the write-once information storage medium.

  In the wobble address area 610, 3 address bits are set with 12 wobbles (see FIG. 51). That is, one address bit is composed of four consecutive wobbles. As described above, in this embodiment, the address information is distributed and arranged every three address bits. If the wobble address information 610 is centrally recorded in one place in the information storage medium, it becomes difficult to detect all information when the surface has dust or scratches. As in this embodiment, wobble address information 610 is distributed and arranged for every three address pits (12 wobbles) included in one wobble data unit 560 to 576, and information that is gathered for each address bit that is an integral multiple of 3 address bits. Even if it is difficult to detect information in one place due to the recording and the influence of dust and scratches, it is possible to detect information of other information.

  As described above, the wobble address information 610 is distributed and the wobble address information 610 is completely arranged for each physical segment, so that the address information is known for each physical segment. You can know the current position in units.

In the present embodiment, since the NRZ method is employed as shown in FIG. 51, the phase does not change in four consecutive wobbles in the wobble address area 610. The wobble sync area 580 is set using this feature. That is, by setting a wobble pattern that cannot be generated in the wobble address information 610 for the wobble sync area 580, the arrangement position of the wobble sync area 580 can be easily identified. In the present embodiment, the wobble address areas 586 and 587 that constitute one address bit by four consecutive wobbles are characterized in that one address bit length is set to a length other than four wobbles in the wobble sync area 580 position. is there. That is, in the wobble sync area 580, as shown in FIGS. 53A and 53B, the area (IPW area) in which the wobble bit is “1” is different from 4 wobbles as “6 wobble → 4 wobble → 6 wobble”. As shown in FIGS. 53 (c) and 53 (d), a wobble pattern change that cannot occur in the wobble data portion is set. When the method of changing the wobble cycle as described above is used as a specific method for setting the wobble pattern that cannot be generated in the wobble data portion to the wobble sync area 580, (1) In the wobble signal detection portion 135 of FIG. The wobble detection (wobble signal determination) can be continued stably without losing the PLL related to the slot position 512 (FIG. 51) of the wobble being performed. (2) Address bit boundary performed in the wobble signal detection unit 135 of FIG. The effect that the wobble sync region 580 and the modulation start marks 561 and 582 can be easily detected by the positional shift is produced. As shown in FIG. 53, the present embodiment is also characterized in that the wobble sync area 580 is formed in 12 wobble cycles and the length of the wobble sync area 580 is made to match the 3 address bit length. Thus, the start position of wobble address information 610 (positioning position of wobble sync area 580) is detected by allocating all the modulation areas (16 wobbles) in one wobble data unit # 0560 to wobble sync area 580. The ease is improved. This wobble sync area 580 is arranged in the first wobble data unit in the physical segment. Thus, by arranging the wobble sync area 580 at the head position in the physical segment, there is an effect that the boundary position of the physical segment can be easily extracted only by detecting the position of the wobble sync area 580.

  As shown in FIGS. 53 (c) and 53 (d), in wobble data units # 1561 to # 11571, an IPW area (see FIG. 52) as a modulation start mark precedes address bits # 2 to # 0. Has been placed. In the non-modulation regions 592 and 593 arranged at the positions preceding the NPW waveform, the wobble signal detector 135 shown in FIG. 9 detects the switching point from the NPW to the IPW. The position of the modulation start mark is extracted.

For reference, the contents of the wobble address information 610 in the rewritable information storage medium shown in FIG. 54 (a) are: (1) Physical segment address 601
... Information indicating a physical segment number in a track (within one revolution in the information storage medium 221).

(2) Zone address 602
... zone numbers in the information storage medium 221 are shown.

(3) Parity information 605
... It is set for error detection during playback from wobble address information 610, and 14 address bits from reservation information 604 to zone address 602 are individually added for each address bit unit, and the addition result is even or odd. The result of exclusive OR (Exclusive OR) for each address bit unit for a total of 15 address bits including 1 address bit of the address parity information 605 is “1”. The value of the parity information 605 is set.

(4) Unity area 608
As described above, each wobble data unit is set to include a modulation area 598 for 16 wobbles and non-modulation areas 592 and 593 for 68 wobbles, and the non-modulation areas 592 and 593 are occupied by the modulation area 598. The ratio is greatly increased. Furthermore, the occupation ratio of the non-modulation areas 592 and 593 is expanded to further improve the accuracy and stability of extraction (generation) of the reproduction reference clock or recording reference clock. In the unity region 608, the NPW region is continuous, and is a non-modulated region having a uniform phase.

Is recorded. The number of address bits assigned to each piece of information is shown in FIG. As described above, the wobble address information 610 is separated into three address bits and distributed in each wobble data unit. Even if a burst error occurs due to dust or scratches on the surface of the information storage medium, the probability that the error spreads across different wobble data units is very low. Therefore, it is devised to reduce the number of times of crossing between different wobble data units as a place where the same information is recorded, and to match the boundary between each piece of information and the wobble data unit. As a result, even if a burst error occurs due to dust or scratches on the surface of the information storage medium and specific information cannot be read, wobble address information can be read so that other information recorded in each other wobble data unit can be read. The playback reliability is improved.

  As shown in FIGS. 54A to 54C, the last arrangement of the unity areas 608 and 609 in the wobble address information 610 is also a major feature of this embodiment. As described above, since the wobble waveform is NPW in the unity areas 608 and 609, the NPW continues substantially in as many as three consecutive wobble data units. By using this feature, the wobble signal detection unit 135 of FIG. 9 is easily arranged at the end of the wobble address information 610 by searching for a place where the NPW continues for a length of three wobble data units 576. The position of the unity area 608 can be extracted, and the effect that the start position of the wobble address information 610 can be detected using the position information is produced.

  Among the various address information shown in FIG. 54A, the physical segment address 601 and the zone address 602 indicate the same value between adjacent tracks, whereas the groove track address 606 and the land track address 607 are between adjacent tracks. The value changes with. Accordingly, the indefinite bit area 504 appears in the area where the groove track address 606 and the land track address 607 are recorded. In order to reduce this indefinite bit frequency, in the present embodiment, for the groove track address 606 and the land track address 607, addresses (numbers) are displayed using gray codes. The gray code means a code in which the converted code when the original value changes by “1” changes only by “1 bit” everywhere. As a result, the frequency of indefinite bits can be reduced to stabilize signal detection not only for the wobble detection signal but also for the reproduction signal from the recording mark.

As shown in FIGS. 54B and 54C, in the write-once information storage medium, the wobble sync area 680 is arranged at the physical segment head position as in the rewritable information storage medium, and the physical segment head position or the adjacent physical segment is located. It is easy to detect the boundary position between them. The type identification information 721 of the physical segment shown in FIG. 54 (b) indicates other modulations in the same physical segment by indicating the arrangement position of the modulation area in the physical segment in the same manner as the wobble sync pattern in the wobble sync area 580 described above. Since the location of the region 598 can be predicted in advance and the next modulation region detection can be prepared in advance, there is an effect that the signal detection (discrimination) accuracy in the modulation region can be increased. Specifically: When the physical segment type identification information 721 is “0”, all of the physical segments shown in FIG. 56B are in the primary array location (Primary Position), or FIG. Represents the mixed state of the primary location and the secondary location shown in FIG.
When the physical segment type identification information 721 is “1”, it indicates that all of the physical segments are in the secondary position as shown in FIG. 56C.

  As another embodiment relative to the above embodiment, the location of the modulation area in the physical segment can be indicated by a combination of the wobble sync pattern and the physical segment type identification information 721. By combining the two types of information, three or more types of modulation area arrangement patterns shown in FIGS. 56B to 56D can be expressed, and a plurality of modulation area arrangement patterns can be provided. In the above embodiment, the arrangement location of the modulation area in the physical segment including the wobble sync area 580 and the physical segment type identification information 721 is shown. However, the present invention is not limited to this. The wobble sync area 580 and the physical segment type identification information 721 may indicate the location of the modulation area in the next physical segment. In this case, when tracking is continuously performed along the groove region, the arrangement location of the modulation region in the next physical segment is known in advance, and there is an effect that it takes a long preparation time for detecting the modulation region.

The layer number information 722 in the write-once information storage medium shown in FIG. 54 (b) indicates which one of the recording layers is a single-sided recording layer or a single-sided two recording layer
• “0” means “L0 layer” (front layer on the laser beam incident side) in the case of a single-sided one recording layer medium or a single-sided two recording layer
・ When “1”, “L1 layer” (two layers on one side of the laser beam)
Means.

  The physical segment order information 724 indicates the relative physical segment arrangement order in the same physical segment block. As apparent from the comparison with FIG. 54A, the start position of the physical segment order information 724 in the wobble address information 610 matches the start position of the physical segment address 601 in the rewritable information storage medium. For address detection using wobble signal in information recording / reproducing device that can use both rewritable information storage media and write-once information storage media by improving the compatibility between media types by matching the physical segment order information position to the rewritable format The control program can be shared and simplified.

  The data segment address 725 in FIG. 54B describes address information of the data segment with a number. As described above, in this embodiment, one ECC block is composed of 32 sectors. Therefore, the lower 5 bits of the physical sector number of the sector arranged at the head in the specific ECC block coincide with the sector number of the sector arranged at the head position in the adjacent ECC block. When the physical sector number is set so that the lower 5 bits of the physical sector number of the sector arranged at the head in the ECC block is “00000”, the physical sector numbers of all sectors existing in the same ECC block are set. Values in the lower 6th bit and above match. Therefore, the lower 5 bit data of the physical sector number of the sector existing in the same ECC block is removed, and the address information obtained by extracting only the data of the lower 6 bits or more is used as the ECC block address (or ECC block address number). . Since the data segment address 725 (or physical segment block number information) recorded in advance by wobble modulation matches the ECC block address, when the position information of the physical segment block by wobble modulation is displayed by the data segment address, the physical sector number Compared to display, the data amount is reduced by 5 bits, and the present position is easily detected at the time of access.

  54B and 54C, the CRC code 726 is a CRC code (error correction code) for 24 address bits from the physical segment type identification information 721 to the data segment address 725 or the segment information 727 to the physical segment order information 724. Even if the wobble modulation signal is partially misread with the CRC code for the 24 address bits, the CRC code 726 can partially correct the wobble modulation signal.

  In the write-once information storage medium, the area corresponding to the remaining 15 address bits is assigned to the unity area 609, and the twelfth to 16th wobble data units are all NPW (the modulation area 598 has not exist).

  The physical segment block address 728 in FIG. 54 (c) is an address set for each physical segment block constituting one unit from seven physical segments, and the physical segment block address 728 in the data lead-in DTRDI is physical. The segment block address is set to “1358h”. The value of this physical segment block address is sequentially incremented by 1 from the first physical segment block in the data lead-in DTLDI to the last physical segment block in the data lead-out DTLDO, including the data area DTA.

  The physical segment order information 724 represents the order of each physical segment in one physical segment block, and is set to “0” for the first physical segment and “6” for the last physical segment.

  In the embodiment of FIG. 54 (c), the physical segment block address 728 is characterized by being arranged at a position preceding the physical segment order information 724. For example, as in the RMD field 1 shown in Table 18, address information is often managed with this physical segment block address. When accessing a predetermined physical segment block address according to these management information, the wobble signal detection unit 135 shown in FIG. 9 first detects the location of the wobble sync area 580 shown in FIG. Thereafter, the information recorded immediately after the wobble sync area 580 is sequentially decoded. If there is a physical segment block address at a position preceding the physical segment sequence information 724, the physical segment block address is first decoded, and whether the physical segment block address is a predetermined physical segment block address without decoding the physical segment sequence information 724. Since the determination can be made, there is an effect that the accessibility using the wobble address is improved.

The segment information 727 includes type identification information 721 and a reserved area 723. The type identification information 721 represents the arrangement location of the modulation area in the physical segment. When the value of the type identification information 721 is “0b”, it represents the state shown in FIG.
In the case of “1b”, the state shown in FIG. 56 (c) or (d) described later is shown.

  In FIG. 54 (c), the present embodiment is also characterized in that the type identification information 721 is arranged immediately after the wobble sync area 580. As described above, the wobble signal detector 135 shown in FIG. 9 first detects the location of the wobble sync area 580 shown in FIG. 54 (c), and then the information recorded immediately after the wobble sync area 580. Decipher sequentially. Accordingly, by arranging the type identification information 721 immediately after the wobble sync area 580, the arrangement location of the modulation area in the physical segment can be immediately confirmed, so that the access processing using the wobble address can be speeded up.

  In the recordable information storage medium of the present embodiment, a recording mark is formed on the groove area, and the CLV recording method is adopted. In this case, since the wobble slot position between adjacent tracks is shifted, it has been explained that interference between adjacent wobbles is likely to ride on the wobble reproduction signal. In order to remove this influence, in the present embodiment, the modulation area is shifted so that the modulation areas do not overlap each other between adjacent tracks.

  Specifically, as shown in FIG. 55, a primary arrangement location (Primary Position) 701 and a secondary arrangement location 702 (Secondary Position) can be set as the arrangement location of the modulation region. Basically, all the arrangement locations are temporarily arranged at the primary arrangement location, and when a place where the modulation area partially overlaps between adjacent tracks is generated, the position is partially shifted to the secondary arrangement location. For example, in FIG. 55, when the modulation area of the groove area 505 is set as the primary arrangement location, the modulation area of the adjacent groove area 502 and the modulation area of the groove area 506 partially overlap. Shift to the secondary location. As a result, there is an effect that the wobble address can be stably reproduced by preventing the interference between the modulation areas of the adjacent tracks in the reproduction signal from the wobble address.

  The specific primary location and secondary location regarding the modulation area are set by switching the location within the same wobble data unit. In this embodiment, since the occupation rate of the non-modulation area is set higher than that of the modulation area, switching between the primary arrangement place and the secondary arrangement place can be performed only by changing the arrangement within the same wobble data unit. Specifically, in the primary arrangement location (Primary Position) 701, as shown in FIGS. 53A and 53C, the modulation area 598 is arranged at the head position in one wobble data unit, and the secondary arrangement location 702 is obtained. In (Secondary Position), as shown in FIGS. 53 (b) and 53 (d), a modulation area 598 is arranged at the latter half position in one wobble data unit 560-571.

  In this embodiment, the range in which the primary placement location (Primary Position) 701 and the secondary placement location 702 (Secondary Position) shown in FIG. It is specified in the scope of the segment. That is, as shown in FIG. 56, three types (plural types) of (b) to (d) are provided in the modulation area arrangement pattern in the same physical segment, and the physical segment is obtained from the information of the type identification information 721 of the physical segment. When the wobble signal detection unit 135 in FIG. 9 identifies the arrangement pattern of the modulation areas in this area, the arrangement location of the other modulation areas 598 in the same physical segment can be predicted in advance. As a result, it is possible to increase the accuracy of signal detection (discrimination) in the modulation area because the next modulation area detection can be prepared in advance.

  FIG. 56B shows the arrangement of wobble data units in the physical segment, and the numbers described in each frame indicate the wobble data unit numbers in the same physical segment. The 0th wobble data unit is called a sync field 711 as shown in the first stage, and a wobble sync area exists in the modulation area in the sync field. The first to eleventh wobble data units are called address fields 712, and address information is recorded in the modulation area in the address field 712. Further, in the 12th to 16th wobble data units, the wobble patterns are all NPW unity fields 713.

  The marks “P” shown in FIGS. 56B, 56C, and 56D indicate that the modulation area is the primary location in the wobble data unit, and the mark “S” indicates the wobble. It shows that the modulation area is the secondary location in the data unit. The mark “U” indicates that the wobble data unit is included in the unity field 713 and there is no modulation area. The arrangement pattern of the modulation area shown in FIG. 56 (b) indicates that the entire physical segment is the primary arrangement position (Primary Position), and the arrangement pattern of the modulation area shown in FIG. 56 (c) is physical. This indicates that all the segments are in the secondary position. In FIG. 56 (d), the primary location and the secondary location are mixed in the same physical segment, and the modulation area becomes the primary location in the 0th to 5th wobble data units. In the 11th wobble data unit, the modulation area is a secondary location. As shown in FIG. 56D, the overlapping of the modulation areas between adjacent tracks can be prevented by halving the primary arrangement place and the secondary arrangement place with respect to the area where the sync field 711 and the address field 712 are combined. I can do it.

  A method for recording the above-described data segment data on a physical segment or physical segment block in which address information is recorded in advance by the wobble modulation described above will be described. Both the rewritable information storage medium and the recordable information storage medium record data in units of recording clusters as a unit for continuously recording data. FIG. 57 shows the layout in this recording cluster. One or more (integer) data segments are continuously connected in the recording clusters 540 and 542, and extended guard fields 528 and 529 are set at the beginning or end thereof. In order to avoid a gap between adjacent recording clusters when data is newly added or rewritten in units of recording clusters 540 and 542, they are physically overlapped with adjacent recording clusters and partially overlapped. Extended guard fields 528 and 529 are set in the recording clusters 540 and 542 for writing. As the position of the extended guard fields 528 and 529 set in the recording clusters 540 and 542, the extended guard field 528 is arranged at the end of the recording cluster 540 in the embodiment of FIG. When this method is used, the extended guard field 528 comes after the postamble area 526 shown in FIG. 58 (a). In particular, in the case of a rewritable information storage medium, the postamble area 526 may be accidentally destroyed at the time of rewriting. In addition, the postamble area 526 at the time of rewriting can be protected, and the reliability of position detection using the postamble area 526 at the time of data reproduction can be ensured. As another embodiment, an extended guard field 529 can be arranged at the beginning of the recording cluster 542 as shown in FIG. In this case, as shown in FIG. 57 (b) and FIG. 58, the extended guard field 529 comes immediately before the VFO area 522. Therefore, the VFO area 522 can be made sufficiently long when rewritten or appended. The PLL pull-in time related to the reference clock during 525 reproduction can be increased, and the reproduction reliability of data recorded in the data field 525 can be improved. In this way, a recording cluster representing a rewrite unit is structured by one or more data segments, so that a small amount of data is often rewritten many times and PC data (PC file) and a large amount of data are once written. Thus, it is possible to easily perform mixed recording processing of AV data (AV file) continuously recorded on the same information storage medium. In other words, data used for personal computers is often rewritten with a relatively small amount of data many times. Therefore, if the data unit for rewriting or appending is set as small as possible, the recording method is suitable for PC data. In this embodiment, as shown in FIG. 32, an ECC block is composed of 32 physical sectors. Therefore, rewriting or appending in units of data segments including only one ECC block is the minimum unit for efficient rewriting or appending. It becomes. Therefore, the structure in the present embodiment in which one or more data segments are included in a recording cluster representing a rewriting unit or a write-once unit is a recording structure suitable for PC data (PC file). In AV (Audio Video) data, it is necessary to record a very large amount of video information and audio information continuously without being interrupted. In this case, continuously recorded data is recorded together as one recording cluster. When the random shift amount, the structure in the data segment, the attribute of the data segment, and the like are switched for each data segment constituting one recording cluster at the time of AV data recording, it takes time for switching processing, and continuous recording processing becomes difficult. In this embodiment, as shown in FIG. 57, a large number of data segments are formed by continuously arranging data segments of the same format (without changing attributes and random shift amounts and without inserting specific information between data segments). Information recording / reproducing apparatus which not only provides a recording format suitable for AV data recording in which recording data is continuously recorded, but also simplifies the structure in the recording cluster and simplifies the recording control circuit and the reproduction detection circuit. Alternatively, the price of the information reproducing apparatus can be reduced. The data structure in which the data segments (excluding the extended guard field 528) in the recording cluster 540 shown in FIG. 57 are continuously arranged is the reproduction-only information storage medium shown in FIG. 48 (b) and FIG. 48 (c). The same structure as the recordable information storage medium shown in FIG. As described above, since the data structure is common to all information storage media regardless of the read-only format / recordable format / rewritable format, the compatibility of the media is ensured, The detection circuit of the information reproducing apparatus can be used in common, and high reproduction reliability can be ensured and the price can be reduced.

  The structure shown in FIG. 57 inevitably causes the random shift amounts of all data segments to match within the same recording cluster. In the rewritable information storage medium, a recording cluster is recorded with a random shift. In the present embodiment, since the random shift amounts of all the data segments in the same recording cluster 540 are the same, when playback is performed across different data segments in the same recording cluster 540, in the VFO area (522 in FIG. 58). Synchronizing (resetting the phase) is not necessary, and it is possible to simplify the reproduction detection circuit at the time of continuous reproduction and to ensure high reliability of reproduction detection.

  FIG. 58 shows a rewritable data recording method for recording in the rewritable information storage medium. In the following, the rewritable information storage medium will be mainly described, but the write-once method for the write-once information storage medium is basically the same method. The layout in the recording cluster in the rewritable information storage medium of the present embodiment will be described using an example taking the layout of FIG. 57 (a). In the present embodiment in which the layout shown in 57 (b) may be adopted, rewriting of rewritable data is performed in units of recording clusters 540 and 541 shown in FIGS. 58 (b) and 58 (e). As will be described later, one recording cluster includes one or more data segments 529 to 531 and an extended guard field 528 arranged last. That is, the start of one recording cluster 531 coincides with the start position of the data segment 531 and starts from the VFO area 522. When a plurality of data segments 529 and 530 are continuously recorded, a plurality of data segments 529 and 530 are continuously arranged in the same recording cluster 531 as shown in FIGS. In addition, since the buffer area 547 existing at the end of the data segment 529 and the VFO area 532 existing at the beginning of the next data segment are continuously connected, the phase between them (the recording reference clock at the time of recording) is Match. When the continuous recording is finished, the extended guard area 528 is arranged at the last position of the recording cluster 540. The data size of the extended guard area 528 has a size of 24 data bytes as data before modulation.

  As can be seen from the correspondence between FIG. 58A and FIG. 58C, the rewritable guard areas 461 and 462 include the postamble areas 546 and 536, the extra areas 544 and 534, the buffer areas 547 and 537, and the VFO area 532, respectively. 522 and pre-sync areas 533 and 523, and the extended guard field 528 is arranged only at the continuous recording end location. The rewrite or additional writing has the characteristic of this embodiment in the place where rewriting or additional writing is performed so that the extended guard area 528 and the rear VFO area 522 partially overlap at the overlapping part 541 at the time of rewriting. This prevents the generation of gaps (areas where no recording marks are formed) between the recording clusters 540 and 541, and eliminates inter-layer crosstalk in a recordable information storage medium having two recording layers on one side, thereby producing a stable reproduction signal. It can be detected.

In this embodiment, the rewritable data size in one data segment is 67 + 4 + 77376 + 2 + 4 + 16 = 77469 (data byte).
It becomes. One wobble data unit 560 is 6 + 4 + 6 + 68 = 84 (wobble)
Since 17 physical units 550 are composed of 17 wobble data units, and the lengths of 7 physical segments 550 to 556 match the length of one data segment 531. Within the length of one data segment 531 is 84 × 17 × 7 = 9996 (wobble)
Is placed. Therefore, 77496 ÷ 9996 = 7.75 (data byte / wobble) corresponds to one wobble from the above formula.

  As shown in FIG. 59, the overlapping portion of the next VFO area 522 and the extended guard field 528 comes after 24 wobbles from the start position of the physical segment, but the wobble sync area 580 extends from the start of the physical segment 550 to 16 wobbles. Thereafter, 68 wobbles are in the unmodulated area 590. Therefore, a portion where the next VFO region 522 after 24 wobbles and the extended guard field 528 overlap is in the non-modulation region 590. In this way, by making the start position of the data segment come after the start position 24 wobbles of the physical segment, not only the overlapping portion is in the unmodulated area 590 but also the detection time of the wobble sync area 580 and the preparation time of the recording process Therefore, stable and accurate recording processing can be guaranteed.

  The recording film of the rewritable information storage medium in this embodiment uses a phase change recording film. In the phase change recording film, the deterioration of the recording film starts in the vicinity of the rewrite start / end position. Therefore, when the recording start / recording end at the same position is repeated, the number of rewrites is limited due to the deterioration of the recording film. In the present embodiment, in order to alleviate the above problem, at the time of rewriting, the recording start position is shifted at random by shifting by Jm + 1/12 data bytes as shown in FIG.

  58 (c) and (d), the top position of the extended guard field 528 and the top position of the VFO area 522 coincide with each other in order to explain the basic concept, but strictly speaking, in this embodiment, as shown in FIG. The leading position of the VFO area 522 is randomly shifted.

A DVD-RAM disk that is a current rewritable information storage medium also uses a phase change recording film as a recording film, and the recording start / end positions are shifted at random to improve the number of rewritings. The maximum shift amount range when random shift is performed on the current DVD-RAM disc is set to 8 data bytes. The channel bit length in the current DVD-RAM disc (as modulated data recorded on the disc) is set to an average of 0.143 μm. In the rewritable information storage medium embodiment of the present embodiment, the average length of channel bits is (0.087 + 0.093) ÷ 2 = 0.090 (μm) from Table 7. When the length of the physical shift range is adjusted to the current DVD-RAM disc, the minimum required length as the random shift range in this embodiment is 8 bytes × ( 0.143 μm ÷ 0.090 μm) = 12.7 bytes. In this embodiment, in order to ensure the ease of the reproduction signal detection process, the unit of the random shift amount is matched with the “channel bit” after modulation. In the present embodiment, ETM modulation (Eight to Twelve modulation) that converts 8 bits into 12 bits is used for modulation, so that the expression representing the random shift amount is based on the data byte as Jm / 12 (data byte).
Represented by As a possible value of Jm, using the value of the above formula, 12.7 × 12 = 152.4
Therefore, Jm is 0 to 152. For the above reasons, if the range satisfies the above formula, the random shift range length matches the current DVD-RAM disc, and the same number of rewrites as the current DVD-RAM disc can be guaranteed. In this embodiment, in order to secure the number of rewrites more than the current number, a slight margin is provided for the minimum necessary length,
The length of the random shift range is 14 (data bytes)
Set to. From these formulas, 14 x 12 = 168, so the value that Jm can take is 0 to 167.
Was set. By setting the random shift amount to a range larger than Jm / 12 (0 ≦ Jm ≦ 154) as described above, the length of the physical range with respect to the random shift amount matches that of the current DVD-RAM. There is an effect that the same number of repeated recordings as in the RAM can be guaranteed.

  In FIG. 58, the lengths of the buffer area 547 and the VFO area 532 in the recording cluster 540 are constant. As is clear from FIG. 57A, the random shift amount Jm of all the data segments 529 and 530 is the same value everywhere in the same recording cluster 540. When one recording cluster 540 including a large amount of data segments is continuously recorded, the recording position is monitored from the wobble. That is, the position of the wobble sync area 580 shown in FIG. 54 is detected, and the recording position on the information storage medium is confirmed simultaneously with the recording while counting the number of wobbles in the non-modulation areas 592 and 593 of FIG. At this time, a wobble slip (recording at a position shifted by one wobble period) occurs due to a wobble count error or rotation unevenness of the rotary motor rotating the information storage medium, and the recording position on the information storage medium may be shifted. It is rare. The information storage medium according to the present embodiment is characterized in that when the recording position shift generated as described above is detected, adjustment is performed in the rewritable guard area 461 in FIG. 58 to correct the recording timing. . Here, the H format is described, but this basic concept is also adopted in the B format as described later. In FIG. 58, important information in which missing or overlapping bits are not permitted is recorded in the postamble area 546, the extra area 544, and the presync area 533, but a specific pattern is repeated in the buffer area 547 and the VFO area 532. As long as this repetitive boundary position is secured, omission or duplication of only one pattern is allowed. Therefore, in this embodiment, adjustment is made in the buffer area 547 or the VFO area 532 in the guard area 461, and the recording timing is corrected.

As shown in FIG. 59, in the present embodiment, the actual start point position serving as a position setting reference is set to coincide with the position of wobble amplitude “0” (wobble center). However, since the wobble position detection accuracy is low, in this embodiment, as described in “± 1 max” in FIG. 59, the actual start point position allows a deviation amount of up to ± 1 data byte ”. Yes.

  58 and 59, the random shift amount in the data segment 530 is set to Jm (as described above, the random shift amounts of all the data segments 529 in the recording cluster 540 are the same), and then the data segment 531 to be additionally written is recorded. Let the random shift amount be Jm + 1. As possible values of Jm and Jm + 1 shown in the above equation, for example, an intermediate value is taken and Jm = Jm + 1 = 84, and when the actual start point position accuracy is sufficiently high, as shown in FIG. 58, an extended guard field 528 is obtained. And the start position of the VFO area 522 coincide with each other.

On the other hand, when the data segment 530 is recorded at the maximum rear position and the data segment 531 to be added or rewritten later is recorded at the maximum front position, the head position of the VFO area 522 is moved into the buffer area 537. Up to 15 data bytes can be entered. Specific important information is recorded in the extra area 534 immediately before the buffer area 537. Therefore, in this embodiment, the length of the buffer area 537 needs to be 15 data bytes or more. In the embodiment shown in FIG. 58, the data size of the buffer area 537 is set to 16 data bytes in consideration of a margin of 1 data byte.

As a result of the random shift, if a gap is generated between the extended guard area 528 and the VFO area 522, interlayer crosstalk occurs during reproduction due to the gap when the single-sided two-recording layer structure is adopted. Therefore, even if a random shift is performed, the extended guard field 528 and the VFO region 522 are partly overlapped so that a gap is not generated. Therefore, in this embodiment, the length of the extended guard field 528 needs to be set to 15 data bytes or more. Since the subsequent VFO area 522 is 71 data bytes long enough, even if the overlap area of the extended guard field 528 and the VFO area 522 is somewhat wide, there is no problem in signal reproduction (for reproduction in the non-overlapping VFO area 522). This is because sufficient time is secured to synchronize the reference clock). Therefore, the extended guard field 528 can be set to a value larger than 15 data bytes. As described above, the wobble slip rarely occurs during continuous recording, and the recording position may be shifted by one wobble period. Since one wobble period corresponds to 7.75 (≈8) data bytes, in this embodiment, the length of the extended guard field 528 is set to (15 + 8 =) 23 data bytes or more. In the embodiment shown in FIG. 58, the length of the extended guard field 528 is set to 24 data bytes in consideration of a margin of 1 data byte, similarly to the buffer area 537.

  In FIG. 58 (e), it is necessary to accurately set the recording start position of the recording cluster 541. In the information recording / reproducing apparatus of this embodiment, the recording start position is detected by using a wobble signal recorded in advance on a rewritable or write-once information storage medium. As shown in FIG. 53, except for the wobble sync area 580, the pattern changes from NPW to IPW in units of 4 wobbles. On the other hand, in the wobble sync area 580, the wobble switching unit is partially shifted from 4 wobbles, so that the position of the wobble sync area 580 is most easily detected. Therefore, in the information recording / reproducing apparatus of this embodiment, after detecting the position of the wobble sync area 580, preparation for the recording process is performed and recording is started. Therefore, the start position of the recording cluster 541 needs to come in the non-modulation area 590 immediately after the wobble sync area 580. FIG. 59 shows the contents. A wobble sync area 580 is arranged immediately after switching of the physical segment. The length of the wobble sync area 580 is 16 wobble cycles. Further, after detecting the wobble sync area 580, 8 wobble cycles are required in preparation for recording processing in anticipation of a margin. Therefore, as shown in FIG. 59, the head position of the VFO area 522 existing at the head position of the recording cluster 541 needs to be arranged at least 24 wobbles behind the physical segment switching position even when a random shift is considered.

  As shown in FIG. 58, the recording process is performed many times in the overlapping portion 541 at the time of rewriting. When rewriting is repeated, the physical shape of the wobble groove or wobble land changes (deteriorates), and the wobble reproduction signal quality from there changes. In the present embodiment, as shown in FIG. 58 (f), an overlapping portion 541 at the time of rewriting or additional writing is avoided from being in the wobble sync area 580 or wobble address area 586, and is recorded in the unmodulated area 590. Devised. In the non-modulation area 590, only a constant wobble pattern (NPW) is repeated. Therefore, even if the wobble reproduction signal quality partially deteriorates, it can be interpolated using the preceding and following wobble reproduction signals. As described above, since the position of the overlapping portion 541 at the time of rewriting or additional writing is set to be within the non-modulation area 590, the deterioration of the wobble reproduction signal quality due to the shape deterioration in the wobble sync area 580 or the wobble address area 586 is prevented. This produces an effect that a stable wobble detection signal from the wobble address information 610 can be guaranteed.

  Next, an embodiment of a write-once method of write-once data recorded on the write-once information storage medium is shown in FIG. A write start point is a position 24 wobbles behind the boundary position of the physical segment block. Data newly added from here forms a VFO area of 71 data bytes, and then a data area (data field) in the ECC block is recorded. This write start point coincides with the end position of the buffer area 537 of the recording data recorded immediately before, and after the extended guard field 528 is formed by the length of 8 data bytes, the recording end position of the additional recording data (writing End point). Therefore, when data is additionally recorded, 8 data bytes are overlapped and recorded in the extended guard field 529 recorded immediately before and the newly added VFO area.

Chapter 8 Explanation of B Format B Format Optical Disc Specifications Table 21 shows the specifications of B format optical discs using a blue-violet laser light source. B format optical discs are classified into rewritable type (RE disc), read-only type (ROM disc), and write once type (R disc). As shown in Table 21, any type other than the standard data transfer rate is used. It is a common specification and it is easy to realize compatible drives common to different types. In contrast to the current DVD with two 0.6 nm thick disk substrates, the B format provides a recording layer on a 1.1 nm thick disk substrate and a 0.1 nm transparent It is a structure covered with a simple cover layer. Single-sided, double-layer media are also defined.

[Error correction method]
In the B format, an error correction method called a picket code that can efficiently detect a burst error is adopted. Pickets are inserted into main data (user data) columns at regular intervals. The main data is protected by a powerful and efficient Reed-Solomon code. The picket is protected by a second very powerful and efficient Reed-Solomon code separate from the main data. In decoding, the picket is first error-corrected. The correction information can be used to estimate the position of the burst error in the main data. The symbols at these positions are flagged as “Erasure” which is used when correcting the code word of the main data.

  FIG. 61 shows the structure of a picket code (error correction block). The error correction block (ECC block) in the B format is composed of 64 Kbytes of user data as in the H format. This data is protected by a very strong Reed-Solomon code LDC (long distance code).

  The LCD consists of 304 code words. Each codeword consists of 216 information symbols and 32 parity symbols. That is, the code word length is 248 (= 216 + 32) symbols. These code words are interleaved every 2 × 2 in the vertical direction of the ECC block, and form an ECC block of 152 (= 304/2) bytes × 496 (= 2 × 216 + 2 × 32) bytes in the horizontal direction. .

  The interleave length of picket is 155 × 8 bytes (there are 8 control code correction sequences in 496 bytes), and the interleave length of user data is 155 × 2 bytes. For the 496 bytes in the vertical direction, every 31 rows is a recording unit. In the parity symbol of the main data, two groups of parity symbols are nested for each row.

  In the B format, a picket code embedded in the ECC block in a shape like a “pillar” at regular intervals is adopted. A burst error is detected by looking at the error status. Specifically, four picket rows were arranged at equal intervals in one ECC block. There is also an address in the picket. The picket contains its own parity.

  Since the symbols in the picket string also need to be corrected, the pickets in the three right columns are error-corrected and protected by BIS (burst indicator subcode). This BIS is composed of 30 information symbols and 32 parity symbols, and the codeword length is 62 symbols. From the ratio between the information symbol and the parity symbol, it can be seen that there is an extremely strong correction capability.

  BIS codewords are interleaved and stored in three picket sequences each consisting of 496 bytes. Here, both LDC and BIS codes have the same number of parity symbols per codeword of 32. This means that one common Reed-Solomon decoder can decode both LDC and BIS.

  When decoding data, first, picket string correction processing is performed by BIS. Thereby, the location of the burst error is estimated, and a flag called Erasure is set at that location. This is used when correcting the code word of the main data.

  The information symbols protected by the BIS code form an additional data channel (side channel) separate from the main data. Address information is stored in this side channel. Address information error correction uses a dedicated Reed-Solomon code prepared separately from the main data. This code consists of 5 information symbols and 4 parity symbols. As a result, it is possible to grasp a high-speed and highly reliable address independent of the main data error correction system.

[Address format]
Like the CD-R disc, the RE disc has a very narrow groove as a recording track. The recording mark is written only in the convex portion when seen from the laser beam incident direction among the concave and convex portions (on-groove recording).

  The address information indicating the absolute position on the disk is embedded by slightly wobbling (meandering, swinging) the groove as in a CD-R disk or the like. The signal is modulated, and digital data representing "1" or "0" is placed on the meandering shape or period. FIG. 62 shows the wobble method. The meandering amplitude is only ± 10 nm in the disk radial direction. 56 wobbles (about 0.3 mm in length on the disk) are address information 1 bit = ADIP unit (described later).

  In order to write fine recording marks with almost no positional deviation, it is necessary to generate a stable and accurate recording clock signal. Therefore, we focused on a system in which the main frequency component of wobble is single and the groove is smoothly continuous. If the frequency is single, a stable recording clock signal can be easily generated from the wobble component extracted by the filter.

  Timing information and address information are added to the wobble based on this single frequency. For this purpose, “modulation” is applied. As this modulation method, one that is less prone to error even if there are various distortions inherent to the optical disc is selected.

  The wobble signal distortion generated in the optical disk is classified into the following four when sorted by cause.

  (1) Disc noise: Disturbance of the surface shape (surface roughness) generated in the groove portion during manufacturing, noise generated in the recording film, crosstalk noise leaking from recorded data, and the like.

  (2) Wobble shift: A phenomenon in which the detection sensitivity is lowered when the wobble detection position is shifted relative to the normal position in the recording / reproducing apparatus. It is likely to occur immediately after a seek operation.

  (3) Wobble beat: Crosstalk generated between the wobble signal of the track to be recorded and the adjacent track. This occurs when the rotation control method is CLV (constant linear velocity) and there is a deviation in the angular frequency of adjacent wobbles.

  (4) Defects: caused by local defects due to dust or scratches on the disk surface.

  In the RE disc, two different wobble modulation schemes are combined in a form that produces a synergistic effect on condition that they have high tolerance against all of these four different types of signal distortion. This is because resistance to four types of signal distortion, which is generally difficult to achieve with only one type of modulation system, can be obtained without side effects.

  The two systems are the MSK (minimum shift keying) system and the STW (saw tooth wobble) system (FIG. 63). The name of the STW is named because its waveform resembles a “tooth profile”.

  In the RE disk, one bit of “0” or “1” is expressed by a total of 56 wobbles. These 56 are called a unit, that is, an ADIP (address in pregroove) unit. When 83 ADIP units are continuously read, an ADIP word indicating one address is obtained. The ADIP word is composed of 24-bit address information, 12-bit auxiliary data, a reference (calibration) area, error correction data, and the like. In the RE disc, three ADIP words are assigned to each RUB (recording unit block, 64 Kbyte unit) for recording main data.

  The ADIP unit consisting of 56 wobbles is roughly divided into the first half and the second half. The first half of the wobble numbers from 0 to 17 is the MSK system, and the second half of the 18th to 55th is the STW system, which is smoothly connected to the next ADIP unit. One ADIP unit can represent one bit. Depending on whether it is “0” or “1”, the position of the wobble subjected to the MSK modulation is changed in the first half, and the shape of the sawtooth wave is changed in the second half.

  The first half of the MSK system is further divided into three wobble areas subjected to MSK modulation and a monotone wobble cos (wt) area. First, the three wobbles from No. 0 to No. 2 always start with MSK modulation in any ADIP unit. This is called a bit sync (an identifier indicating the start position of the ADIP unit).

  After that, the monotone wobble is next. Then, data is represented by the number of monotone wobbles up to the next three wobbles subjected to MSK modulation that reappears. Specifically, “11” is “0”, and “9” is nine. Data is distinguished by the difference between two wobbles.

  The MSK method uses a local phase change of the fundamental wave. In other words, the region where there is no phase change is dominant. This region is effectively used as a place where the phase of the fundamental wave does not change even in the STW system.

  A region subjected to MSK modulation has a length of three wobbles. The first part is 1.5 times the frequency of monotone wobble (cos (1.5 wt)), the second is the same frequency as monotone wobble, and the third is 1.5 times the frequency again. Double to restore the original phase. In this way, the polarity of the second (center) wobble is just inverted with respect to the monotone wobble, and this is detected. The first start point and the third end point are exactly in phase with the monotone wobble. Therefore, a smooth connection without discontinuities is possible.

  On the other hand, there are two types of waveforms in the latter half of the STW system. One is a waveform that rises steeply toward the outer periphery of the disk and returns with a gentle inclination toward the center of the disk, and the other is a waveform that rises with a gentle inclination and returns sharply. The former represents data “0” and the latter represents data “1”. The reliability of data is increased by indicating the same bit using both the MSK method and the STW method in one ADIP unit.

  When the STW method is expressed mathematically, it can be said that a second harmonic sin (2 wt) having an amplitude of ¼ is added to or subtracted from the fundamental wave cos (wt). However, the zero cross point is the same as the monotone wobble regardless of whether the STW system represents “0” or “1”. That is, in extracting the clock signal from the fundamental wave component common to the MSK monotone wobble part, the phase is not affected at all.

  As described above, the MSK method and the STW method work to compensate each other's weak points.

  Table 22 shows the ADIP units.

  The basic unit of the address wobble format is an ADIP unit. Each group of 56 NML (Nominal Wobble Length) is called an ADIP unit. One NML is equal to 69 channel bits. Different types of ADIP units are defined by inserting modulation wobbles (MSK marks) at specific locations within the ADIP unit (see FIG. 63). 83 ADIP units constitute one ADIP word. The minimum segment of data recorded on the disc exactly matches three consecutive ADIP words. Each ADIP word contains 36 information bits (24 of which are address information bits).

  Tables 23 and 24 show the configuration of one ADIP word.

  One ADIP word includes 15 nibbles. As shown in Table 25, 9 nibbles are information nibbles.

  Other nibbles are used for ADIP error correction. The fifteen nibbles constitute a codeword of [15, 9, 7] Reed-Solomon code.

  The code word includes nine information nibbles, six information nibbles record address information, and three information nibbles record auxiliary information (for example, disc information).

  The Reed-Solomon code of [15, 9, 7] is non-systematic, and prior knowledge can increase the Hamming distance by “Informed Decoding”. “Informed Decoding” means that all codewords have a distance of 7 and all codewords of nibble n0 have a distance of 8, so prior knowledge about n0 increases the Hamming distance. Nibble n0 includes a layer index (3 bits) and an MSB of a physical sector number. If nibble n0 is known, the distance increases from 7 to 8.

  FIG. 64 shows the track structure. Here, the track structure of the first layer (the first layer is a layer far from the laser light source) and the second layer of the single-sided dual-layer disc will be described. Grooves are provided to enable push-pull tracking. Several types of track shapes are used. The first layer L0 and the second layer L1 have different tracking directions. In the first layer, the tracking direction is from left to right in the drawing, and in the second layer, the tracking direction is from right to left. The left side of the figure is the inner circumference of the disc, and the right side is the outer circumference. The BCA area consisting of the first layer straight groove, the pre-recording area consisting of the HFM (High Frequency Modulated) groove, and the wobble groove area in the rewriting area correspond to the H format lead-in area, and the second layer rewriting. The wobble groove area in the area, the pre-recording area composed of HFM (High Frequency Modulated) grooves, and the BCA area composed of straight grooves correspond to the H format lead-out area. However, in the H format, the lead-in area and the lead-out area are recorded not in the groove system but in the pre-pit system. The phase of the HFM groove is shifted between the first layer and the second layer so that interlayer crosstalk does not occur.

  FIG. 65 shows a recording frame. As shown in FIG. 61, user data is recorded for each 64 Kbyte section. Each row of the ECC cluster is converted into a recording frame by adding a frame sync bit and a DC control bit. A 1240-bit (155-byte) stream in each row is converted as follows. A 1240-bit stream has 25-bit data at the head, the following is divided into 45-bit data, a 20-bit frame sync is added before the 25-bit data, and 1-bit is added after the 25-bit data. DC control bits are added, and thereafter, similarly, 1-bit DC control bit is added after 45-bit data. A block including the first 25-bit data is defined as DC control block # 0, and 45-bit data and 1-bit DC control bit are defined as DC control blocks # 1, # 2,. 496 recording frames are referred to as a physical cluster.

  The recording frame is 1-7PP modulated at a rate of 2/3. A modulation rule is applied to 1268 bits excluding the head frame sync to obtain 1902 channel bits, and a 30-bit frame sync is added to the head of the whole. That is, 1932 channel bits (= 28 NML) are configured. The channel bits are NRZI modulated and recorded on the disc.

Frame Sync Structure Each physical cluster includes 16 address units. Each address unit includes 31 recording frames. Each recording frame begins with a frame sync of 30 channel bits. The first 24 bits of the frame sync violate the 1-7PP modulation rules (including a run length twice 9T). The 1-7PP modulation rule uses (1, 7) PLL modulation method and performs parity preserve / prohibit PMTR (repeated minimum transition runlength). Parity Preserve controls the so-called DC (direct current) component of the code (reduces the DC component of the code). The remaining 6 bits of the frame sync change to identify the 7 frame syncs FS0, FS1,. These 6-bit symbols are chosen such that the distance with respect to the deviation amount is 2 or more.

  Seven frame syncs make it possible to obtain more detailed position information than only 16 address units. Of course, it is insufficient to identify 31 recording frames with only 7 different frame syncs. Accordingly, seven frame sync sequences are selected from 31 recording frames so that each frame can be identified by a combination of its own frame sync and any one of the four preceding frames.

  FIG. 66 shows the structure of the recording unit block RUB. The unit of recording is called RUB. As shown in FIG. 5A, the RUB is composed of a 40 wobble data run-in, a 496 × 28 wobble physical cluster, and a 16 wobble data run out. Data run-in and data run-out allow sufficient data buffering to facilitate completely random overwriting. One RUB may be recorded one by one, or a plurality of RUBs may be recorded continuously as shown in FIG.

  Data run-in mainly consists of 3T / 3T / 2T / 2T / 5T / 5T repeating patterns, in which two frame syncs (FS4, FS6) serve as indicators to indicate the start position of the next recording unit block. 40 cbs apart from each other.

  Data run-out starts at FS0, followed by 9T / 9T / 9T / 9T / 9T / 9T pattern indicating the end of data following FS0, mainly repeating 3T / 3T / 2T / 2T / 5T / 5T Consists of patterns.

  FIG. 67 shows the structure of data run-in and data run-out.

  FIG. 68 is a diagram showing the arrangement of data relating to wobble addresses. The physical cluster is 496 frames. A total of 56 wobbles (NWL) of data run-in and data run-out is 2 × 28 wobbles, which corresponds to two recording frames.

1 RUB = 496 + 2 = 498 recording frames 1 ADIP unit = 56 NWL = 2 recording frames 83 ADIP units = 1 ADIP word (including 1 ADIP address)
3ADIP word = 3 × 83 ADIP unit 3ADIP word = 3 × 83 × 2 = 498 recording frame When recording data on a write once type disc, it is necessary to record the next data in succession to the already recorded data It is. If there is a gap between the data, it cannot be played back. Therefore, in order to record (overwrite) the first data run-in area of the subsequent recording frame so as to overlap with the last data run-out area of the preceding recording frame, as shown in FIG. The guard 3 area is arranged at the end of the. FIG. 4A shows a case where only one physical cluster is recorded, and FIG. 4B shows a case where a plurality of physical clusters are continuously recorded. Only after the run-out of the last cluster, the guard 3 is recorded. Provide an area. In this way, each recording unit block recorded independently or a plurality of recording unit blocks recorded continuously is terminated in the guard 3 area. The guard 3 area ensures that there is no unrecorded area between the two recording unit blocks.

Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

  135: Wobble signal detection unit 141: Information recording / reproducing unit 143 ... Control unit 151 ... Modulation circuit 152 ... Demodulation circuit 156 ... Viterbi decoder 159 ... Descramble circuit 161 ... ECC encoding circuit 162 ... ECC Decoding circuit, 171... Data ID part and IED part extraction part, 172... Error check part of data ID part, 174.

Claims (3)

  Storage medium with L → H characteristics.   A reproduction method for reproducing information from a storage medium having L → H characteristics.   A recording method for recording information on a storage medium having L → H characteristics.

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