JP2002208139A - Information recording method, information recorder, and information processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information recording method with which recording can be carried out in uniform signal characteristics over the entire surface of optical disk medium when the optical disk medium is divided into two or more recording areas in the radial direction and is recorded, by using the simple method of driving the optical disk medium with the CAV(Constant Angular Velocity) system, while maintaining compatibility with the recording format of the conventional reproduction-only media. SOLUTION: When the optical disk medium is divided into a plurality of recording areas in the radial direction and is recorded according to the data amount to record in the rotary drive by the CAV system, recording can be carried out in uniform characteristics over the entire surface of optical disk medium regardless of the interruption and restart of the recording operation, by computing and recording the recording power of the following recording area, while reproducing the recording part of the end part of each recording area, and adding the correction in the approximate expression on the basis of the reproduction result.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video DVD (D
digital Video or Versatile Disk) or DVD-R
DVD-R (Recodable) or DVD having format compatibility with read-only DVD media such as OM
The present invention relates to an information recording method, an information recording device, and an information processing device using this device on an optical disk medium such as a RW (ReWritable) disk.

[0002]

2. Description of the Related Art With the spread of multimedia, video D
Read-only media such as VD and DVD-ROM, and information recording media such as write-once DVD-R using a dye material as a recording layer and rewritable DVD-RW using a phase change material have been developed. .

The information (sectors in this example) recorded on these DVD media has a format as shown in FIG. In such a format,
As shown in FIG. 11D, data (sectors) are continuously recorded on all tracks of the medium at a constant linear density.

In order to provide an information recording medium in a format compatible with the read-only medium, a method of controlling the rotation speed of the information recording medium (media) has conventionally been used as shown in FIG.
As shown in (b), CLV (Constant Linear Veloc)
(constant linear velocity) method, the rotation speed of the medium is controlled so that the rotation speed is inversely proportional to the track radius, and the linear velocity of the track is always kept constant while the information is recorded at a constant recording channel clock frequency. We are recording.

However, in order to control the rotational speed by the CLV method, it is necessary to change the rotational speed of the medium in order to keep the track linear velocity constant. That is, since the rotation of the spindle motor for rotating the medium is accompanied, a large rotation torque is required, and a large-sized and high-cost motor is required. Also, at the time of seeking, it takes a long time to complete the shifting of the spindle motor, so compared to HDDs and MO drives,
There is a disadvantage that it takes a lot of access time.

[0006] In view of the above, in order to perform recording on the medium while keeping the rotation speed of the medium constant without performing speed change control, the format of information recorded on the medium is as shown in FIG. It is also considered. That is, as shown in FIG. 12C, the frequency of the channel clock to be recorded on the medium is made smaller on the inner circumference side and increased on the outer circumference side in proportion to the radial position of the track. In this case, since the recording linear velocity becomes smaller on the inner peripheral side and increases on the outer peripheral side, the recording linear density is constant as shown in FIG. Further, it is possible to record information on the medium by keeping the number of rotations (rotation speed) of the medium constant as shown in FIG. 12B, that is, by the CAV (Constant Angular Velocity) method.

[0007] This eliminates the need for rotational speed change control of the spindle motor that rotationally drives the medium.
A low-rotation torque is sufficient, and a small and low-cost motor can be used. Further, since no shift is performed, a shift waiting time during seeking is not required, and the access time can be greatly reduced.

However, dye-based DVD-Rs in which pits (marks) are generally formed in a heat mode
In a medium or a phase change type RW medium, the pulse width and recording power of a recording pulse train due to laser emission at the time of recording are optimized at a specific recording linear velocity, so that marks and spaces formed at different recording linear velocities are formed. The state changes. That is, if there is a deviation in the setting of the pulse width or the recording power, the heat capacity required for forming the mark may be excessive or insufficient, or the heating temperature reached for each mark length with respect to the optimum decomposition temperature may be different. The average length varies, the uniform pulse width cannot be obtained due to the difference in the optimum pulse width, and thickening or thinning (a so-called tear-shaped mark) occurs depending on the mark length, thereby deteriorating the jitter characteristics.

In this respect, for example, according to Japanese Patent Application Laid-Open No. 5-225570, at least two test recording areas are required in order to determine the optimum recording light amount corresponding to the entire recordable area of each optical disc in a relatively short time. The optimum recording light amount is obtained at a recording linear velocity equal to the position, and the optimum recording light amount is obtained by an interpolation routine.
By performing an interpolation process or an extrapolation process on the optimum recording light quantity at one recording linear velocity, the optimum recording light quantity at all the recording linear velocities is obtained.

According to Japanese Patent Application Laid-Open No. Hei 5-274678, in order to reduce the laser power required for recording without deteriorating the jitter characteristics, the optical disk is rotated at a constant number of rotations, and is different depending on the area. In a method of recording information at a higher frequency in an outer peripheral region than in an inner peripheral region by irradiating a light beam intensity-modulated according to an information signal based on a reference clock, the light beam is referred to in each region. A light beam that periodically emits pulses at a frequency that is an integral multiple of the clock frequency, and
When the light beam is applied to the outer peripheral region, the duty ratio of the pulse emission is set to be larger than when the light beam is applied to the inner peripheral region.

Further, according to Japanese Patent Application Laid-Open No. H10-106008, an optical disk, an optical head, a synchronizing signal generating means, a VCO, a phase comparing means, A controller and a recording signal generating means are provided, and by changing the pulse height and width of the recording signal in accordance with the recording linear velocity, recording can always be performed under the best recording conditions.

[0012]

In the case of these publications, in the CAV system, control is performed such that the set value of any element of the recording pulse such as the duty ratio of pulse emission is varied according to the recording linear velocity. However, these controls are effective when the recording sensitivity distribution of the optical disk medium is manufactured uniformly over the entire surface of the disk and the variation with respect to the set value of the recording power is kept constant over the entire surface of the disk. However, in an actual information recording apparatus, it is difficult to perform uniform recording over the entire surface of a disk due to variations in recording sensitivity of the disk and power fluctuations and wavelength fluctuations due to temperature characteristics of the LD, especially for DVD recording media. there were.

That is, since a plurality of fluctuation factors at the time of recording interact with the characteristics of the recording information (RF signal) such as the jitter characteristic, the recording method described in these publications is not sufficient and is not always sufficient. Recording cannot be performed with uniform signal characteristics over the entire surface of the medium, and a desired effect cannot always be obtained. In particular, when recording a large amount of data on an optical disk medium, the optical disk medium is divided into a plurality of recording areas in the radial direction due to the relationship between the data transfer speed from the host side and the slowness of the recording speed. When recording while controlling so as to interrupt / restart recording every time, it is difficult to record with uniform signal characteristics over the entire surface of the optical disk medium.

Accordingly, the present invention provides an optical disk medium which divides an optical disk medium into a plurality of recording areas in the radial direction and drives the optical disk medium to rotate while recording information while sequentially updating the setting of a recording pulse train. Recording with uniform signal characteristics over the entire surface of the optical disk medium using a simple method without controlling the speed of rotation of the optical disk and maintaining compatibility with the recording format of conventional read-only media. Information recording method,
It is an object to provide an information recording device or an information processing device.

Further, according to the present invention, the recording pulse train is corrected in accordance with the non-uniformity of the disc characteristics and the fluctuation of the recording apparatus, thereby preventing the deterioration of the jitter characteristics and improving the P of the reproduction clock.
An object of the present invention is to provide an information recording method, an information recording device, or an information processing device in which the LL also operates stably.

Furthermore, the present invention provides a method of correcting the entire surface of an optical disk medium by using a simple setting of a recording pulse train for all recording linear velocities and a simple recording power correction method even when performing recording by CAV control. It is an object of the present invention to provide an information recording method, an information recording device, or an information processing device capable of performing recording with low jitter over a period of time.

[0017]

According to the first aspect of the present invention, there is provided an information recording method for recording information on an optical disk medium having a recording layer on which mark information is recorded by a laser beam having an emission waveform by a recording pulse train. The recording clock cycle is changed in accordance with the change in the linear velocity, and the recording is performed so that the recording linear density becomes substantially constant, and is calculated by an approximate expression for obtaining the recording power corresponding to the change in the recording linear velocity. When recording is performed using the set recording power, a recording portion at the end portion where recording of a predetermined recording region has been completed is reproduced from recording regions obtained by dividing the optical disc medium into a plurality of portions in the radial direction, and obtained by a reproduced signal. From the obtained signal characteristics, an approximate expression in which the recording power is corrected so as to obtain an ideal signal characteristic is derived, and the approximate expression in which the correction is performed in accordance with each recording area is obtained. And to record using the recording power calculated Te.

Therefore, the CA for keeping the disk rotation speed constant
When the recording linear velocity changes due to the V control, even if the optimum condition during recording deviates from the set value, the recording pulse can be corrected to the optimum recording pulse for each recording linear velocity, and the recording pulse can be corrected over the entire optical disk medium. It is possible to record uniform characteristics. In particular, when the optical disc medium is divided into a plurality of recording areas in the radial direction according to the amount of data to be recorded and recorded, a recording portion at the end of each recording area is reproduced and a correction is made based on the reproduction result. However, since the recording power of the next recording area is calculated and recorded, uniform characteristics can be recorded over the entire surface of the optical disk medium regardless of the interruption / resumption of the recording operation.

According to a second aspect of the present invention, there is provided the information recording method according to the first aspect, wherein a plurality of recording linear velocities at least one of a minimum recording linear velocity and a maximum recording linear velocity in a predetermined test writing area on the optical disc medium are provided. Test recording with the recording power of the above, calculate the optimum recording power from the change in the signal characteristics obtained from each reproduction signal, and obtain the minimum recording power obtained from the test writing or from the disc information previously recorded on the optical disc medium. Using the optimum recording power of both the recording linear velocity and the maximum recording linear velocity, a first approximate expression for obtaining the recording power corresponding to the change of the recording linear velocity is derived. The recording calculated by the first approximation formula for the first recording area at the innermost part among the recording areas obtained by dividing the medium into a plurality of parts in the radial direction. Performs recording using a word, the first
Immediately after the recording of the recording area is completed, the recording portion at the end of the first recording area is reproduced, and the recording power is corrected so that ideal signal characteristics can be obtained from the signal characteristics obtained by the reproduced signal. The second and subsequent approximation formulas are derived, and recording is performed using the recording power calculated by the second and subsequent approximation formulas corresponding to each of the second and subsequent recording regions.

Accordingly, in realizing the first aspect of the present invention, the calculation of the approximate expression for each recording area and the method of correcting the approximate expression become clear. In particular, even if the in-plane sensitivity variation of the disc or the recording power fluctuation depending on the temperature characteristic or mechanical fluctuation of the recording apparatus occurs, the deviation from the optimum recording power can be corrected, and the good recording quality can be obtained over the entire optical disc. Recording becomes possible.
Furthermore, the modulation data of the recording information at the end of each divided recording area and the start of the subsequent recording area is continuously recorded.

According to a third aspect of the present invention, in the information recording method of the first or second aspect, the optical disk medium is a dye-based optical disk using a dye material as a recording layer.

Therefore, when recording is performed for each of the divided recording areas on a so-called write-once optical recording medium, it is possible to record uniform characteristics over the entire surface of the optical disk medium.

According to a fourth aspect of the present invention, in the information recording method according to the first or second aspect, the optical disk medium is a phase change type optical disk using a phase change type material as a recording layer.

Therefore, when recording is performed for each divided recording area on a so-called rewritable optical recording medium, it is possible to record with uniform characteristics over the entire surface of the optical disk medium.

According to a fifth aspect of the present invention, when recording is performed on an optical disk medium having a recording layer on which mark information is recorded by a laser beam having a light emission waveform by a recording pulse train, a recording clock cycle is changed in accordance with a change in a recording linear velocity. When recording is performed by changing the recording linear density so that the recording linear density becomes substantially constant, test write recording is performed with a plurality of recording powers in a predetermined test write area of the optical disk medium, and the obtained reproduction signal characteristics change. An information recording apparatus for calculating an optimum recording power from the optical disc medium, setting the optical disc medium to be divided into a plurality of recording areas in a radial direction, and then performing recording while updating the recording power for each recording area. Reproduction signal detection means for calculating a modulation degree or asymmetry from a reproduction signal at the end of the recording area immediately after recording on the predetermined recording area; and A recording power calculation for calculating an approximate expression for calculating a recording power according to the recording linear velocity, and calculating a corrected approximate expression adapted to a next predetermined recording area after recording on the predetermined recording area. Means, recording control means for interrupting recording for each recording in the predetermined recording area and correcting the approximation formula, and resuming recording from the beginning of the next predetermined recording area, and a pulse corresponding to the recording linear velocity. Laser light source control means for setting the width and generating the recording pulse train, and laser light source driving means for updating the amount of light emitted from the laser light source at any time according to the calculated recording power.

Therefore, the CA for keeping the disk rotation speed constant
When the recording linear velocity changes due to the V control, even if the optimum condition during recording deviates from the set value, the recording pulse can be corrected to the optimum recording pulse for each recording linear velocity, and the recording pulse can be corrected over the entire optical disk medium. It is possible to record uniform characteristics. In particular, when the optical disc medium is divided into a plurality of recording areas in the radial direction according to the amount of data to be recorded and recorded, a recording portion at the end of each recording area is reproduced and a correction is made based on the reproduction result. However, since the recording power of the next recording area is calculated and recorded, uniform characteristics can be recorded over the entire surface of the optical disk medium regardless of the interruption / resumption of the recording operation. In particular, recording with CAV control is possible with a simple and small circuit configuration.

According to a sixth aspect of the invention, an information processing apparatus includes the information recording apparatus according to the fifth aspect.

Therefore, since the information recording device according to claim 5 is built in, when a large amount of data is recorded on the optical disk medium, the data transfer speed from the information processing device main body side and the recording speed of the information recording device. Due to the slow speed and the like, even if the optical disc medium is divided into a plurality of recording areas in the radial direction and recording is performed while controlling to interrupt / restart recording for each recording area, Recording can be performed with uniform signal characteristics over the entire surface, and it can be effectively used as an information storage device.

[0029]

FIG. 1 shows a first embodiment of the present invention.
This will be described with reference to FIG. First, as a setting of a basic recording pulse train used in a dye-based optical disk as an optical disk medium, as shown in FIG. 1, recording is performed for each mark data length nT (n is an integer of 3 to 14, T is a recording clock cycle). The pulse train is composed of a plurality of heating pulses.

The basic settings of the recording pulse train include the number of pulses nx (x is 1 or 2) constituting the recording pulse train for each mark data length nT, and the pulse width of the head heating pulse for the recording clock cycle T. There are a ratio Ttop, a duty ratio Tmp of the heating pulse of the subsequent intermediate multi-pulse portion, a ratio Ttail of a pulse width of the last heating pulse to the recording clock cycle T, and the like. The setting of the recording power includes a recording power Pw of a heating pulse portion for forming a mark, and a bias power Pb for forming a cooling pulse portion and a space in the mark. Regarding the recording power, the state of mark formation is determined by the recording linear velocity Lv.
It is well known that the optimum value of the recording power increases as the recording linear velocity increases because of the strong correlation.
Further, the ratio ρ = Pmax / of the recording power Pmax at the outermost peripheral position (ie, the maximum recording linear velocity) to the optimal recording power Pmin at the innermost peripheral position (ie, the minimum recording linear velocity), which is the linear velocity dependence of the disk. There is Pmin. In the present embodiment, the recording clock cycle T
It is necessary to make more detailed settings in accordance with the recording linear velocity for the ratio Ttop of the pulse width of the first heating pulse to Ttop, the ratio Ttail of the pulse width of the last heating pulse to the recording clock cycle T, and the ratio ρ of the recording power. is there. In the present embodiment, a detailed correction is made especially for the recording power.

Generally, a dye-based DV having a diameter of 120 mm is used.
When recording control is performed on the D disk by the CAV method, the recording linear velocity becomes about 3.5 m / s at the innermost position of the disk and about 8.5 m / s at the outermost position, and the recording clock frequency becomes Is about 26.2 MHz at the innermost position and about 63.7 MHz at the outermost position. About 2.4 like this
When performing recording requiring a change in recording linear velocity by a factor of two on a dye-based DVD disk, if the same pulse width and recording power setting value of the same recording pulse train are used over the entire area, the higher the recording linear velocity becomes ( In the outer periphery), the preheating by the first heating pulse becomes excessive or insufficient, and the modulation degree (Modulation) of the RF signal varies, or the symmetry (asymmetry) of the RF signal varies widely. In addition, the optimum value of the pulse width of the last heating pulse in the subsequent multi-pulse portion also deviates, and the recording mark width becomes non-uniform. In the present embodiment, as described below, it is possible to have a uniform signal characteristic from the innermost position to the outermost position of the optical disk medium and to perform recording with low jitter.

First, as shown in FIG. 2, at the minimum recording linear velocity at the innermost position, the number of heating pulses constituting the recording pulse train is n-1 (n is the mark data length), and the ratio Ttop of the top heating pulse width is Ttop. 1.30T, the ratio Tmp of the subsequent intermediate multi-pulse width and the ratio Ttail of the last heating pulse width
Is set to 0.65 T, and the optimum recording power Pwmin of the heating pulse is set to 9.0 mW. These setting values are typical numerical values of a dye-based recording disk, and are different optimum values depending on various tunings and types of recording materials.
Then, as shown in FIG. 2, the set values of the ratio Ttop and the ratio Ttail and the ratio ρ = Pw / Pmin of the recording power Pw are all changed so as to increase in accordance with the increase in the recording linear velocity. Optimum amount of heat can be applied to the beginning and end of the mark, and recording can be performed with the optimum recording power, the mark width can be formed uniformly and the jitter characteristics can be maintained well. it can.

As described above, when recording is performed by the CAV method in which the recording linear velocity changes depending on the radial position, good recording can be performed by updating these set values as follows. That is, as a specific setting example, as shown in FIG. 2, the ratio Ttop of the pulse width of the head heating section to the recording clock cycle T is set to 1.30T at the innermost position (# 49.
7ns) to 1.45T (≒ 22.8n) at the outermost position
s), and the set value is updated and changed so that the accumulated value increases by 0.15T.

The ratio Ttail of the last heating pulse width to the recording clock cycle T is 0.65T at the innermost position.
(≒ 24.8 ns) to 0.85T (≒
13.3 ns) and the cumulative increase is 0.20
The set value is updated and changed so that T becomes longer. Also,
The trailing edge of the head heating section and the trailing edge of the middle multi-pulse section are always set in synchronization with the recording clock, and the ratio Tmp of the middle multi-pulse width is fixed at 0.65T.

Next, regarding the setting of the recording power, the recording power Pw at a desired arbitrary radial position (recording linear velocity) with respect to the optimum recording power Pmin of the heating pulse at the innermost peripheral position (that is, the minimum recording linear velocity). Ratio ρ = Pw /
The set value is updated and changed in accordance with the increase in the recording linear velocity or in accordance with the radial position so that Pmin is increased from 1.0 to 1.50, that is, increased by 0.50 in the increment of the accumulation.

When the recording pulses at the innermost position and the outermost position thus set are compared with each other along the time axis, a light emission waveform as shown in FIG. 3 is obtained.
FIG. 3 illustrates the case of 7T mark data as a representative example of data.

Hereinafter, each set value will be described in more detail. Generally, when recording is performed on a dye-based recording disk at different recording linear velocities, it is known that the recording power is substantially proportional to the square root of the recording linear velocity (for example, Japanese Patent Application Laid-Open No. H10-106008 described above). reference). That is,
If the recording power is Pw, the recording linear velocity is Lv, and the constant is Klv, the recording power is calculated as Pw = Klv√Lv. However, as described above, the ratio Ttop of the leading heating pulse width to the recording clock cycle T, the ratio Ttail to the trailing heating pulse width, and the outermost periphery of the recording power Pw of the heating pulse portion at the innermost peripheral position relative to the minimum recording linear velocity. Ratio ρma of recording power Pw at maximum recording linear velocity at position
In the case where all the set values including x = Pwmax / Pwmin are optimized according to the recording linear velocity Lv, assuming that the recording power ratio is ρ and the constant Kpw is the minimum and maximum recording linear velocity Is the optimal recording power at ρ = Klv × L
The recording power calculated by linear approximation by v + Kpw shows an appropriate value for the recording linear velocity over the entire area. Similarly, by using the set values calculated by linear approximation for the ratio Ttop and the ratio Ttail, it is possible to obtain optimum set values for the recording linear velocity in the entire region. In the set values of the present embodiment, Ttop = 0.030 × Lv + 1.195 Ttail = 0.036 × Lv + 0.544 Pw = Pwmin × ρ = Pwmin × (0.100 × Lv +
0.650). In addition to the function of the recording linear velocity, the setting of the recording pulse may be updated as a function of the radial position, or may be updated in association with an address obtained from the preformat information. Therefore, by using the setting method of updating the set value, it is possible to calculate the optimum set value for an arbitrary recording linear velocity by a simple calculation.

Incidentally, in addition to the above, the combination of the recording pulse trains corresponding to the CAV recording is based on the front edge position and the rear edge position of a rectangular wave pulse which is not a multi-pulse which emphasizes the head portion as used in a CD-R disc. Optimizes settings in detail for changes in recording linear velocity by using a method that corrects the recording linear velocity according to the mark length or a method that corrects both edge positions before and after the head heating pulse as used in DVD-R discs. It is also feasible. In the present embodiment, since the method changes the front edge position of the first heating pulse and the rear edge position of the last heating pulse, the control is easy and the processing can be simplified, but the present invention is not limited to this method.

FIG. 4 shows a more specific set value of the recording power.
As shown in the figure, test writing at the minimum recording linear velocity (OP
Recording is performed while changing the recording power to a plurality of recording powers as C (Optimum Power Control), and the recording power at which the characteristic value obtained from each reproduction signal shows a good value is set as the optimum recording power. In addition, test writing at the maximum recording linear velocity is also performed, and a basic approximate expression of recording power corresponding to the entire surface of the optical disk in CAV recording can be calculated.

In this embodiment, two types of optical disks will be described in detail. First, in the case of a dye-based optical disk, as a characteristic value of a reproduced signal, a 3T modulation degree (asymmetry) is preferable, and Asy. = 0 is set as an optimum detection value.
Here, asymmetry is a value obtained by normalizing the difference between the average level of the longest data amplitude and the average level of the shortest data amplitude of the RF signal with the longest data amplitude as shown in FIG. Shows sex. In the case of EFM pulse modulation, the 14T space level is set to I _14H , 1
4T mark level is I _14L , 3T space level is I
_3H, when the 3T mark level and _{I 3L,} asymmetry _{= [(I 14H + I 14L} ) / 2- (I 3H +
I _3L) / 2] / become _{(I 1} 4H _{-I 14L).} In this embodiment, the optimum recording power (Pmin = 9.0 mW) is calculated in this manner, and the above-described ratio ρmax is calculated.
= 1.50, thereby changing the optimum recording power Pmax at the outermost peripheral position to 13.6 mW. In this OPC, a plurality of recording powers
As shown in FIG. 4A, the recording power dependency of the asymmetry is detected, so that the recording power in the example shown in FIG. 4A is an approximation of the asymmetry Pw = 0.9 × Asy. + 5.9. Formula can be calculated. Further, as described later, by detecting the deviation of the asymmetry during recording, the deviation ΔPw of the recording power can be calculated using the above-described approximate expression.

Next, in the case of a phase-change type optical disk, the characteristic value of the reproduction signal is preferably 14T modulation (Modulation), and Mod. = 0.65 is set as the optimum detection value. Here, Mod. Is a value obtained by normalizing the longest data amplitude of the RF signal at the maximum level of the longest data, as shown in FIG. 5, and indicates the relative ratio of the reflectance difference between the mark of the longest data and the space. . For EFM pulse modulation, the 14T space level _I 14H, when the 14T mark level and _{I 14L,} Modulation ₌ a _{(I 14H -I 14L) / I} 14H. The optimum recording power of the phase-change optical disk is calculated by multiplying the recording power Pt at which the target Mod. Change rate (gradient) γt is obtained by a constant coefficient ρt.
Although a method called a method is often used, the description is omitted in this embodiment. The other figures in the present embodiment are all explanatory views of the dye-based disc.

In this OPC, the recording power dependency of Modulation is detected as shown in FIG. 4B by a plurality of recording powers. Therefore, the recording power in the example shown in FIG. Pw = 8.8 × Mod. ² + 8.9 × Mo
An approximate expression of Modulation of d. + 3.1 can be calculated. Further, by detecting the deviation of Modulation during recording as a reproduction signal, the deviation ΔPw of the recording power can be calculated using the above-described approximate expression. Note that the measured value of Modulation agrees well with the second-order approximation.

Under such a premise method, a specific information recording processing method according to the present embodiment will be described below.

A recording disk such as a CD or a DVD is generally provided with a groove for obtaining a tracking error signal (push-pull signal), and a wobble signal obtained by meandering the groove is superposed. At each recording linear velocity, by detecting with a programmable BPF and demodulating information encoded by frequency modulation or phase modulation, disc-specific address information and disc information can be obtained even for an unrecorded disc. It has become. There is also known a method of generating such information by using cut-off intermittent pits (LPP: Land-PrePit signal) in a land portion.

In particular, the wobble system based on phase modulation in DVD can set the frequency very high.
Since the method using P can demodulate a signal formed in a minute shape equivalent to the data length, highly accurate position detection can be performed for a pre-address on a disk. Therefore, even when recording data is additionally recorded or when recording is interrupted and resumed, by detecting and demodulating the preformat information, it is connected to the end of the immediately preceding recording with an accuracy of about ± 5T. Recording.

Also, it is difficult to accurately connect to the end of the immediately preceding recording from preformat information using a wobble signal of a low band different from the recording data band, such as CD-R or CD-RW. Therefore, a recording clock is generated by using a PLL while reproducing the recorded data up to immediately before, and a recording clock is also generated from a wobble signal, and when a target address from the recorded data is reached. By switching the clock, recording data can be additionally recorded, or recording can be interrupted and resumed.

Therefore, even when a large amount of data is recorded at a stretch, such as write-at-once recording, there is no problem with the reproduced data by resuming the recording data as described above after interrupting the recording midway. Can be recorded so that no occurrences occur.

In the present embodiment, as shown in FIG. 6, when recording is performed by setting a plurality of recording areas divided in the radial direction of the optical disc medium 1, each of the recording areas is set using a method described below. Using the optimum recording power corrected for each recording area, recording is performed uniformly and with good jitter characteristics on the entire surface of the disk.

Therefore, the recording method according to the present embodiment will be described with reference to the flowchart shown in FIG. From the preformat information of the optical disk medium 1 as described above,
Recommended recording pulse width setting values for multiple recording linear velocities such as minimum (innermost) recording linear velocity, maximum (outermost) recording linear velocity, and intermediate (middle) recording linear velocity, and recommended recording power A recommended setting value such as Pw or a recording power ratio ρmax (ratio of recording power at the inner and outer circumferences) is read from the optical disk medium 1 (step S1), and the information recording apparatus uses the test writing area of the optical disk medium 1 The optimum recording power is newly reset by trial writing (OPC) at the minimum (innermost) recording linear velocity and the maximum (outermost) recording linear velocity (S2).

Next, corresponding to the entire surface of the optical disk medium 1,
A set value can be calculated by deriving a basic approximation (first approximation) of each pulse width and recording power with respect to the recording linear velocity (S3), and recording on the entire surface of the optical disc medium 1 according to the data amount to be recorded. The area is divided into a plurality of areas as shown in FIG. 6, and an address area corresponding to each recording area is calculated individually (S4).

Thereafter, in the first recording area (the innermost first recording area), an interval for updating the set value of each pulse width and recording power and an address range corresponding to the interval are allocated. Then, the pulse width and the recording power set value corresponding to the detailed update interval in the first recording area are calculated (S6). Then, the current address is read from the preformat information while performing recording by the actual CAV control (S7), and it is determined whether the current address is within the range for updating the set value, that is, within the address range (S8).
When the value is out of the range (N in S8), by updating to the newly calculated set value (S6, S7), continuous recording can be performed over different recording areas. If it is within the address range (Y in S8), as described above, CA
Recording is performed by V control, and the same processing is repeated until the current recording area end address is reached (S9).

Next, after the recording in the current recording area is completed, jump back to the recorded track at the end of this recording area to perform reproduction, promptly detect asymmetry (S10), and Is determined by calculating the deviation ΔPw from the optimum recording power based on the recording power dependency (Asy or Mod approximation formula) in OPC (S11). (N in S11), the basic approximation expression for setting the recording power is corrected by ΔPw (S12). Approximate expression of recording power setting corrected in this way (second and subsequent approximate expressions)
, The same operation is repeated for the subsequent recording area (S5 to S12).

When it is determined that the reproduction characteristics of the recorded track at the end portion are good (Y in S11), the subsequent recording is performed using the basic approximate expression (first approximate expression) for setting the recording power. The operation for the area may be repeated (S5 to S1
1).

Then, during the period within the address range of the data to be recorded, the recording is performed by the CAV control as described above, and the same processing is repeated until the recording end address is reached (S13), and the recording is completed.

By employing such a recording method, it is possible to greatly reduce the burden of controlling the recording pulse by the controller.

As described above, when a large amount of data is actually recorded on the entire surface of the optical disk medium 1, as shown in FIG. 8, the characteristic value of the reproduced signal is detected for each divided recording area. By performing the recording while correcting the approximate expression of the recording power, even if the in-plane sensitivity variation of the optical disc medium 1 or the recording power variation depending on the temperature characteristic or mechanical variation of the recording apparatus occurs, the optimum recording power can be obtained. The displacement can be corrected, and good recording can be performed over the entire surface of the optical disc medium 1. In particular, in the outer peripheral portion of the disk, as in the case where recording is performed using only the approximate expression of the recording power obtained by the trial writing,
The jitter characteristic does not deteriorate due to a large recording power error and does not exceed an allowable value at the time of reproduction (see FIG. 5).
The solid line in FIG. 5A shows the case where the correction of the approximate expression of the recording power is performed for each of the divided recording areas.
(As shown in (b), the jitter does not exceed the allowable value in any recording area), while maintaining a constant jitter level, 14T modulation (Modulation) or 3T modulation (Resolulu).
) and asymmetry changes can be recorded.

The approximate expression for setting the recording power may be calculated according to the characteristics of the optical disk medium 1 as described above, and can be calculated with high accuracy by linear approximation or other polynomial approximation. The approximate expression of the set value obtained in this way is for the recording linear velocity, and in fact, it is necessary to recognize it by the address information obtained by demodulating the wobble signal or the PLL signal. A specific address is determined from the innermost position to the outermost position, and can be associated with the recording linear velocity.

A second embodiment of the present invention will be described with reference to FIG. The present embodiment relates to an information recording device for recording on the optical disc medium 1 using the above-described information recording method.

First, a rotating mechanism 3 including a spindle motor 2 for rotating the optical disc medium 1 is provided for the optical disc medium 1, and an objective lens for condensing and irradiating the optical disc medium 1 with laser light. An optical head 4 having a light source such as a semiconductor laser or a laser light source is provided so as to be able to move in a seek direction in the disk radial direction. A servo mechanism 5 is connected to an objective lens driving device and an output system of the optical head 4. The optical head 4
A reproduction signal detection means 6 is provided which is involved in a reproduction operation such as calculating a modulation degree or asymmetry from a reproduction signal detected by a light receiving element or the like inside. The servo mechanism 5 and the reproduction signal detecting means 6 include a programmable BPF.
7 is connected. An address demodulation circuit 9 for demodulating an address from a detected wobble signal is connected to the wobble detection unit 8. The address demodulation circuit 9 is connected to a recording clock generator 11 including a PLL synthesizer circuit 10. The drive controller 12 is connected to the PLL synthesizer circuit 10. The drive mechanism 12 connected to the system controller 13 is also connected to the rotation mechanism 3, the servo mechanism 5, the reproduction signal detection means 6, the wobble detection section 8, and the address demodulation circuit 9. The system controller 13 having the recording power calculating means 14 and functioning as the recording control means has an EFM encoder 1
5 and an LD control means 16 as a laser light source control means. The LD control means 16 includes an edge signal generator 18 described later, in addition to a recording pulse train generator 17 that generates a heating multi-pulse control signal including a first heating pulse and a last heating pulse. On the output side of the LD control means 16, an LD which is a driver circuit as a laser light source driving means for driving the semiconductor laser in the optical head 4 by switching the respective driving current sources 19 of the recording power Pw and the bias power Pb. The driving means 20 is connected.

In such a configuration, the center frequency of the BPF corresponding to the recording linear velocity
To the programmable BPF 7, the address demodulation circuit 9 demodulates the address from the wobble signal detected by the wobble detection unit 8, and the PLL synthesizer circuit 10 in which the basic clock frequency is changed by the drive controller 12. , And outputs the recording channel clock to the recording pulse train generator 17.

Next, in order to generate a recording pulse by the semiconductor laser, a recording channel clock and EFM data as recording information are input to the recording pulse train generation unit 17 from the recording clock generation unit 11 and the EFM encoder 15, respectively. The generation unit 17 generates a recording pulse control signal for a recording pulse including a first heating pulse, a last heating pulse, and an intermediate heating multi-pulse. And L
The recording power Pw and the bias power Pb are
Are switched. At the time of recording, the bias current source constantly emits the semiconductor laser with the bias power Pb corresponding to the reproduction power, and the recording pulse control signal generated by the recording pulse train generating unit 17 generates the recording pulse laser as shown in FIG. An emission waveform can be obtained.

Here, in the present embodiment, a multi-stage delay circuit using a gate element and having a delay of about 0.5 ns is arranged as a leading edge signal generator for the first heating pulse in the edge signal generator 18. After being input to an edge selector having a multiplexer configuration, a recording pulse control signal (front edge signal) of a head heating pulse for varying a front edge position by an edge pulse selected by the system controller 13 is generated. Similarly, in the edge signal generation unit in the edge signal generation unit 18 that changes the rear edge position of the last heating pulse, the delay amount 0.5 using the gate element is used.
After a multi-stage delay element of about ns is arranged and input to the edge selector, a recording pulse control signal (back edge signal) of the last heating pulse is generated by the edge pulse selected by the system controller 13.

With such a configuration, each set value is determined as in the information recording method described above, an optimum edge pulse is selected at a desired recording linear velocity, and operation is performed so as to generate a desired recording pulse. ing. When the recording pulse generated by such a configuration is updated at a predetermined interval, each set value changes as shown in FIG.
When a multi-stage delay element is used, each pulse width becomes a fixed value during the update period, and the pulse width ratio and the duty are set so as to change according to the change of the recording channel clock.

Next, as another embodiment of the present invention, a phase comparator, a loop filter, and a VCO (voltage control) are used instead of the multi-stage delay element for the first heating pulse and the last heating pulse in the edge signal generation unit 18. Oscillator) and P using divider
A pulse edge generation unit having an LL configuration may be used. In this configuration, a high-resolution clock obtained by multiplying the recording channel clock by 20 is generated by a PLL, and the pulse edge signal has a resolution of 0.05T, that is, about 1.9 ns to 0.8 ns. After such multi-stage pulse edge signals are input to the multiplexer-configured edge selector, a front edge signal for varying the front edge position of the head heating pulse is generated by the edge pulse selected by the system controller 13. Similarly, an edge signal generation unit 18 that varies the rear edge position of the last heating pulse
Also in the middle edge pulse generation circuit, a pulse edge generation unit having a PLL configuration is arranged, and after being input to the edge selector, the rear edge position of the last heating pulse is varied by the edge pulse selected by the system controller 13. A trailing edge signal has been generated.

With such a configuration, each set value is determined as in the above-described information recording method, an optimum edge pulse is selected at a desired recording linear velocity, and operation is performed so as to generate a desired recording pulse. ing. If the recording pulse generated by such a configuration is updated at predetermined intervals, each set value changes to a sawtooth shape, and P
When the edge pulse generator having the LL configuration is used, the ratios Ttop and Ttail of the respective pulse widths are set to have a constant value even when the recording clock frequency changes during the update period.

It should be noted that the present invention enables uniform recording at the time of CAV recording for any of these configurations,
Various circuit systems can be used as the recording pulse generator. Therefore, according to the information recording apparatus of the present embodiment, basically, the pulse width ratio Ttop of the first heating pulse and the pulse width ratio Ttail of the last heating pulse as described above with a simple and small-scale circuit configuration. In addition, it is possible to perform recording by CAV control using an information recording method that involves updating the setting value of the recording power ratio ρ.

Next, as described in the above-described embodiment, after the test writing (OPC) at the minimum recording linear velocity and the maximum recording linear velocity using the test recording area of the optical disk medium 1, the optical head 4 Playback signal detecting means 6 connected to
Thus, the 3T and 14T mark / space levels of the RF signal are detected, and the system controller 13 calculates asymmetry or modulation (Modulation) and their approximate expressions. Further, the system controller 13 derives a basic approximate expression (first approximate expression) of each pulse width and recording power with respect to the recording linear velocity, and sets a recording area on the entire surface of the optical disc medium 1 according to the amount of data to be recorded. It is divided into a plurality of areas, and the address area corresponding to each recording area is calculated individually.

Next, an interval for updating the set values of the pulse width and the recording power in the first recording area (the innermost first recording area) and an address range corresponding to the interval are allocated. Then, the pulse width and the recording power set value corresponding to the detailed update interval in the first recording area are calculated. The address demodulation circuit 9 reads the current address from the preformat information while performing recording under the CAV control, and determines by the system controller 13 whether the address is within the range for updating the set value, that is, within the address range. When the value is out of the range, the value is updated to the newly calculated set value, and recording is continuously performed.

Immediately after the recording of the current recording area is completed, the recording operation is temporarily interrupted under the control of the system controller 13, and the tracking servo section included in the servo mechanism 5 controls the recording of the trailing end recorded track. The playback is performed by jumping back, and the asymmetry or the modulation (Modulation) is detected by using the playback signal detection means 6. Next, the recording power calculation means 14 of the system controller 13 calculates and determines the deviation ΔPw from the optimum recording power from the recording power dependency (Asy or Mod approximation formula) in OPC, and determines the recording power for the next recording area. Is corrected by ΔPw.

Next, the recording operation is resumed from the start end of the subsequent recording area under the control of the system controller 13 using the corrected approximate expression of the recording power setting (the second and subsequent approximate expressions). The same operation is repeated. As a result, the modulation data of the recording information at the end of each recording area and the start of the succeeding recording area is continuously recorded.

By using the information recording apparatus as described above, even when a large amount of data is actually recorded on the entire surface of the optical disk medium 1, as shown in FIG. By performing recording while detecting the characteristic value of the signal and correcting the approximate expression of the recording power,
Even if the in-plane sensitivity variation of the optical disk medium 1 or the recording power fluctuation depending on the temperature characteristics or mechanical fluctuation of the recording apparatus occurs, the deviation from the optimum recording power can be corrected, and the entire optical disk medium 1 can be corrected. Good recording becomes possible.
Especially, in the outer peripheral portion of the disc, a large recording power error deteriorates the jitter characteristic and exceeds the permissible value at the time of reproduction, as in the case where recording is performed using only the approximate expression of the recording power obtained by test writing. Nonetheless, it is possible to perform recording while suppressing changes in 14T modulation (Modulation), 3T modulation (Resolution) and asymmetry while maintaining a constant jitter level.

A third embodiment of the present invention will be described with reference to FIG. The present embodiment is applied to a personal computer 21 as an information processing device.
In addition to the 5-inch FD drive device 22, the information recording device 23 having the above-described configuration is built in as a DVD-R drive.

According to such a personal computer 21, since the information recording device 23 as described above is built in integrally, the subsequent heating including the first heating pulse and the last heating pulse while rotating the optical disc medium 1 is performed. When recording information using a recording pulse train composed of pulses,
C without controlling the rotation speed of the optical disc medium 1
Recording can be performed with uniform signal characteristics over the entire surface of the optical disc medium 1 using the AV system and maintaining compatibility with the recording format of the conventional read-only medium. In particular, when a large amount of data is recorded on the optical disc medium 1, the optical disc medium 1 is moved in a plurality of directions in the radial direction due to the relationship between the data transfer speed from the personal computer 21 and the recording speed of the information recording device 23. Even in the case where recording is performed while controlling recording to be interrupted / restarted for each recording area by dividing the recording area into recording areas, recording can be performed with uniform signal characteristics over the entire surface of the optical disc medium 1. It can be effectively used as a storage device for information.

[0074]

According to the information recording method of the first aspect of the present invention, when the recording linear velocity changes by the CAV control for keeping the disk rotation speed constant, the optimum condition during the recording is deviated from the set value. In addition, it is possible to correct the recording pulse to the optimum recording pulse for each recording linear velocity, and it is possible to record uniform characteristics over the entire surface of the optical disk medium. When recording is performed by dividing the recording area into a plurality of recording areas, the recording part at the end of each recording area is reproduced, and the recording power of the next recording area is calculated and recorded while making correction based on the reproduction result. Therefore, it is possible to record with uniform characteristics over the entire surface of the optical disk medium regardless of the interruption / resumption of the recording operation.

According to the second aspect of the present invention, in realizing the first aspect of the present invention, the calculation of the approximate expression for each recording area and the correction method thereof become clear. Even if the recording power fluctuates depending on the temperature characteristics and mechanical fluctuations of the recording apparatus, the deviation from the optimum recording power can be corrected, and good recording can be performed over the entire surface of the optical disk. The modulated data of the recording information at the end of each of the recorded areas and the start of the subsequent recording area can be continuously recorded.

According to the third aspect of the present invention, in the information recording method according to the first or second aspect, when recording is performed for each of divided recording areas on a so-called write-once optical recording medium, the entire surface of the optical disk medium is recorded. Recording of uniform characteristics over the entire area becomes possible.

According to the fourth aspect of the present invention, in the information recording method according to the first or second aspect, when recording is performed for each divided recording area on a so-called rewritable optical recording medium, the entire surface of the optical disc medium is recorded. Recording of uniform characteristics over the entire area becomes possible.

According to the information recording apparatus of the present invention, when the recording linear velocity changes due to the CAV control for keeping the disk rotation speed constant, even if the optimum condition during recording deviates from the set value, It is possible to correct the recording pulse to the optimum recording pulse for each recording linear velocity, and it is possible to record with uniform characteristics over the entire surface of the optical disk medium. When recording by dividing into recording areas, the recording part at the end of each recording area is reproduced, and the recording power of the next recording area is calculated and recorded while making correction based on the reproduction result, and recording is performed. Irrespective of whether the recording operation is interrupted or resumed, uniform characteristics can be recorded over the entire surface of the optical disk medium, and recording by CAV control can be performed with a simple and small circuit configuration.

According to the information processing apparatus of the present invention, since the information recording apparatus of the present invention is incorporated,
When recording a large amount of data on an optical disk medium, the optical disk medium is divided into a plurality of recording areas in the radial direction due to the relationship between the data transfer speed from the information processing device itself and the recording speed of the information recording device. Even when recording is performed while controlling recording to be interrupted / restarted for each recording area, recording can be performed with uniform signal characteristics over the entire surface of the optical disk medium, and as an information storage device. It can be used effectively.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a recording pulse train and the like by a first heating pulse and a subsequent heating pulse according to the first embodiment of the present invention.

FIG. 2 is a characteristic diagram of a recording linear velocity versus a pulse width of a recording pulse, a power ratio, and the like.

FIG. 3 is a pulse waveform characteristic diagram showing the innermost and outermost recording pulses relatively along a time axis.

4A is a characteristic diagram showing the recording power dependence of asymmetry of a dye-based disk, and FIG. 4B is a characteristic diagram showing the recording power dependence of the modulation degree of a phase-change disk.

FIG. 5 is an explanatory diagram for explaining asymmetry, modulation degree, and jitter.

FIG. 6 is a plan view showing an example of dividing a recording area of an optical disk medium.

FIG. 7 is a flowchart illustrating a recording method according to the embodiment.

FIG. 8 is a characteristic diagram showing a correction example of a recording power for each recording area.

FIG. 9 is a block diagram showing a second embodiment of the present invention.

FIG. 10 is an external perspective view showing a third embodiment of the present invention.

FIG. 11 is an explanatory diagram showing a conventional example of the CLV method.

FIG. 12 is an explanatory diagram showing a conventional example of a CAV method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical disk medium 6 Reproduction signal detection means 13 Recording control means 14 Recording power calculation means 16 Laser light source control means 20 Laser light source drive means 23 Information recording device

Claims (6)

[Claims] When recording on an optical disk medium having a recording layer on which mark information is recorded by a laser beam having an emission waveform by a recording pulse train, recording is performed by changing a recording clock cycle in accordance with a change in a recording linear velocity. When recording is performed so that the linear density becomes substantially constant, and when recording is performed using the recording power calculated by an approximate expression for obtaining the recording power corresponding to the change in the recording linear velocity, the radius of the optical disc medium is reduced. Of the recording areas divided into a plurality of parts in the direction, the recording part at the end where recording of the predetermined recording area is completed is reproduced, and the recording power of the recording power at which ideal signal characteristics are obtained from the signal characteristics obtained by the reproduced signal. A corrected approximate expression is derived, and recording is performed using the recording power calculated by the corrected approximate expression corresponding to each recording area. Broadcast recording method. 2. Performing test write recording with a plurality of recording powers at a recording linear velocity of at least one of a minimum recording linear velocity and a maximum recording linear velocity in a predetermined test recording area on the optical disk medium, and obtaining from each reproduction signal. Optimum recording power is calculated from the change in the obtained signal characteristics, and the optimum recording power of both the minimum recording linear velocity and the maximum recording linear velocity obtained from the test writing or from the disk information recorded in advance on the optical disk medium is used. hand,
A first approximation formula for obtaining a recording power corresponding to a change in the recording linear velocity is derived, and when recording is actually performed, the innermost peripheral portion of the recording area obtained by dividing the optical disc medium into a plurality in the radial direction is used. The first recording area is recorded using the recording power calculated by the first approximation formula, and immediately after the recording of the first recording area is completed, the end portion of the first recording area is recorded. The second and subsequent approximation expressions in which the recording power is corrected so as to obtain ideal signal characteristics are derived from the signal characteristics obtained by the reproduced signal, and the second and subsequent approximation expressions are derived for each of the second and subsequent recording areas. 2. The information recording method according to claim 1, wherein recording is performed using the recording power calculated by the corresponding second and subsequent approximation formulas. 3. The optical disk medium according to claim 1, wherein the optical disk medium is a dye-based optical disk using a dye material as a recording layer.
Information recording method described. 4. The optical disk medium according to claim 1, wherein the optical disk medium is a phase-change optical disk using a phase-change material as a recording layer.
Or the information recording method according to 2. 5. When recording on an optical disk medium having a recording layer on which mark information is recorded by a laser beam having a light emission waveform by a recording pulse train, the recording clock cycle is changed in accordance with a change in the recording linear velocity to perform recording. When recording is performed so that the linear density becomes substantially constant, test write recording is performed with a plurality of recording powers in a predetermined test write area of the optical disk medium, and the optimum recording power is calculated from the obtained change in the reproduction signal characteristics. An information recording apparatus for setting the optical disk medium to be divided into a plurality of recording areas in a radial direction, and then performing recording while updating recording power for each of the recording areas. Reproduction signal detection means for calculating the degree of modulation or asymmetry from the reproduction signal at the end of the recording area immediately after recording is performed on the recording linear velocity; Recording power calculating means for calculating an approximate expression for calculating the calculated recording power, and calculating a corrected approximate expression adapted to the next predetermined recording area after recording on the predetermined recording area; and After each recording in the recording area, the recording is interrupted and the approximation formula is corrected, and then recording is resumed from the beginning of the next predetermined recording area. An information recording apparatus comprising: a laser light source control unit that generates a pulse train; and a laser light source driving unit that updates a light emission amount of a laser light source as needed according to a calculated recording power. 6. An information processing device incorporating the information recording device according to claim 5.