JPH02118918A - Information processor - Google Patents

Abstract

PURPOSE:To make the additional recording accurate and easy by providing a slot guiding a light beam spot to an optical disk in advance in an information processing unit recording the information on the optical disk in addition and reproducing the information and guiding the spot while the slot is relied upon when the information is recorded. CONSTITUTION:The usual guide slots consist of pits subject to hatching and pits subject to additional recording are shown in dotted lines. The pit interval of the guide slot is that for one additional recording pit, the pit string of the guide slot is meandered in the progressing direction of the slot by a minute interval delta at a period T and the bit interval is selected as a period (t). Thus, since the bit string is meandered by a minute interval delta in the case of the additional recording, the light beam spot traces the pit accurately to apply tracking. That is, a signal 93 from a photodetector 80 is inputted to a digital signal detection circuit 86 in the case of the recording and a signal 87 corresponding to the pit string and a synchronizing clock signal 89 are applied to a disk 66 via an optical system 82.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an information processing device for recording and reproducing digital information.

For example, in an optical disc that stores digital information in a form that can be optically recorded and reproduced, a groove is provided in the optical disc to guide the light beam spot in advance to record additional information. An additional recording method has been proposed that relies on guide grooves to guide the light beam spot and record information (Press informa
tjon Phjlips Nov.

7th1978).

The present inventor has proposed an optical disc with an improved recording method as described in Japanese Patent Application No. 54-7921Q (Japanese Patent Application No. 5B-2138).
Publication No. 6) was published.

That is, FIG. 1 is a diagram showing the structure of an embodiment of an optical disc filed by the present inventors.

In FIG. 1, the pits of the guide groove are shown by solid lines (indicated by hunting), and the additionally recorded pits 1+ are shown by dotted lines. The pit spacing of the guide groove is easy! There is one additional recording pit for the 3rd generation. The pit row of the guide groove is recorded so as to meander with respect to the direction of movement of the groove by a minute amplitude δ at a period T, and the pit intervals are formed so as to be periodic.

The characteristics of such an optical disc are as follows.

That is, when first performing additional recording, the pre-recorded pit row meanderes by a minute amplitude δ, so that the light is Since it is possible to perform a tracking operation in which the beam spot accurately tracks the pit row, it becomes possible to additionally record information pits accurately and easily.

Second, since the bit string is always reproduced at a constant period t, in this type of recording/reproducing device, such as a magnetic disk or magnetic tape, information can be recorded and reproduced accurately even when the speed of the record carrier varies. The PLL (phased lock loop) used is easy to pull in and difficult to remove.

Thirdly, since the position of the additionally recorded pit can be determined based on the position of the pit in the guide groove, there is little timing error when reproducing information.

Fourthly, when additional recording is performed, it is usually a so-called gradation type recording in which holes are made in a metal thin film that is a recording medium. The present invention is described as a guide groove! The present invention can be applied to both a phase type recording form in which pits are formed in the depth direction of the medium and the above-mentioned gradation type recording form. Especially in the case of the light and shade type, there is no need to process the unevenness on the record carrier in advance.
A flat carrier can be used, and control information such as addresses can be optionally added to flexibly meet the demands of disk users.

FIG. 2 is a diagram showing a second example filed by the present inventors. FIG. 2a shows a cross section of the recorded pit row. 1-
Numerals 1 to 1-5 are pits for guiding, and the depth of the pits is 174, which is the wavelength λ of the laser beam used for reproduction. As the record carrier 2, PVC (polyvinyl chloride), which is commonly used as a replica disk, or photoresist coated on a glass disk is suitable.

FIG. 2 is a sectional view of a disc for additional recording. That is, the metal thin film 3 is formed by vapor deposition or the like on the pit row shown in FIG. 2a. FIG. 2C shows the surface portion of FIG. 2, and shows the relationship between the guide pits and additional recording pits in the same way as FIG. 1. Note that this embodiment shows a case where the recording pit and the guide pit are approximately equal in size.

A third example filed by the present inventors is shown in FIG. The cross-sectional form of the guide pit is the same as that shown in Fig. 2a, and the creation of the additional recording disk is also the same as shown in Fig. 2, but in this embodiment, when reproducing the additionally recorded information, the guide pit is In order to make it easier to separate pits and lad fli pits, the sizes of guide pits 5-1 to 5-5 are recorded in pit 6.
The thickness is larger than that of -1 to 6-10. By doing so, it becomes easy to separate the guide pits and the recording pits by using the difference in signal level from the waveform during reproduction.

Further, the 71st example filed by the present inventors is shown in FIG. The cross-sectional form of the guide pit is shown in FIG. 4a. In the figure, the depth of the pit is d. An additional recording disc is created in the same manner as shown in Figure 2, but with guide pits 7-1 to 7-5.
The size of the recording pit is made smaller than that of the recording pit for the same reason as in the second embodiment. In this way, the guide pits can be separated from the reproduced signal waveform. The depth d may be 1/4 of the reproduction laser wavelength λ, but is preferably 1/8.

Furthermore, a fifth example filed by the present inventors is shown in FIG. The guide pits are recorded in the form of shading holes made in a thin metal film formed on the disk surface.

Even in this case, it is desirable to record the guide pits with relatively different sizes in order to distinguish them from the recording pits, as in the third and fourth embodiments. Guide pit 10-1 to 10-
5 is recorded on the metal thin film 3 formed on the substrate 12. By recording the guide pits in a light and shade type, an additional recording disk that can be flexibly handled as described above can be created.

The present invention adds information to such an optical disc! , an information processing center that plays back information from blue-colored optical discs.
This is related to jl.

The present invention will be explained below with reference to Examples.

FIG. 6 is a diagram illustrating the structure of the recording apparatus of the present invention. The optical disc 66 having the above-mentioned guide grooves (guide pits) rotates in the direction of the arrow in the figure about the rotation center shaft 71. A light beam (indicated by diagonal lines) emitted from the semiconductor laser 81 via the optical system 82 is reflected by the optical disk 66 and returns to the optical path again to the flat conductor laser 81 . The scene emitted from the semiconductor laser 81 is then modulated by the light returning from the disk. Therefore, by detecting the light emitted from one end of the semiconductor laser 81 by the photodetector 8°, signals on the disk can be read out.

This detection method is known as the so-called self-coupling effect of semiconductor lasers.

vinegar. What appears below the reproduced signal 93 is a change in the signal envelope due to the guide groove of the present invention.

When the spot of the light beam is completely irradiated to the center of the groove, the repetition period of the envelope is 2T. When the spot deviates from the groove to either the inner or outer circumference of the disc, a signal with a different phase in the circumferential structure T appears on the envelope. Tracking is performed using this.

The (Li number 93) from the detector 80 is input to the tracking signal detector 84, and a tracking signal is detected by a known tracking method disclosed in Japanese Patent Laid-Open No. 49-103515. This tracking signal is sent to the phase compensation circuit 8.
5 to stabilize the control system, and this output drives the linear motor 83 to move the optical head (consisting of a semiconductor laser and an optical system) connected to the linear motor to perform tracking. In this way, the light spot tracks the guide.

In order to perform recording, the signal 93 from the photodetector 80 is first input to the digital signal detection circuit 86, where it is converted by conventional means and methods (for example, converting an analog signal into a digital signal using a comparator, Phase synchronization is also performed to generate a signal synchronized with the clock of the detection signal.

), a signal 87 (hereinafter referred to as a guide pulse signal) corresponding to a pit row forming a guide groove and a synchronization clock 8
Generates 9. The relationship between these two signals on the time axis is shown in FIGS. 7 and 7C, which corresponds to the geometric arrangement of FIG. 1 on the disk surface.

The guide pulse 87 and the synchronization clock 89 are input to an additional recording clock generator 88 to generate a recording clock 95 for additional recording from the two signals.

A recording clock is modulated by a modulation circuit 90 according to a signal from a generator 91 of an information signal to be additionally recorded, and this modulation signal 94 is input to a semiconductor laser activation circuit 92 to modulate the laser oscillation power of the semiconductor laser. .

Here, since the 20 clock 95 does not overlap with the guide pulse 87 on the time axis, according to the above method, additional recording pits are formed between the pits forming the guide grooves.

The simplest modulation method is to create the recording clock 95 by taking the 4+1i alistic 19 logical sum of the signals 87 and 89, and then logically ANDing this with the information signal, as shown in FIGS. 7d and 7e. There is a way to obtain the +U signal 94.

An apparatus for reproducing information recorded in the following manner will be explained with reference to FIG.

In Fig. 8, parts with the same numbers as in Fig. 6 are made by UJ and have the same effect. As shown in FIG. 9, the reproduced signal 100 has a waveform similar to that in FIG. 7a, except that it includes additional recorded information.

The tracking signal is detected in the same manner as in the embodiment of FIG.

FIG. 9 shows a reproduced signal from the optical disc shown in FIG. In this case, since the modulation degree of No. 1a from the additional recording pit is smaller than the modulation degree of No. 11 from the pit forming the guide groove, the additional information is It can be easily separated from inside. That is, by selecting the level of the comparator from the analog reproduced signal, only the guide pulse can be detected, and using this, only the additional information signal can be detected from the data signal.

The reproduced signal 100 is converted to a digital signal by a digital signal converter 101 in the usual manner (converting from an analog signal to a digital signal using a comparator, and forming a pulse whose phase is synchronized with the synchronization signal included in the reproduced signal using PLL). Data signal 1 corresponding to the pit recorded by
06 (shown in Figure 10a) and a synchronized clock 105 (first
(shown in Figure 0) is generated. The two signals are demodulated by the demodulator 102.
and obtain the additionally recorded information signal 107.

The operation of demodulator 102 will be explained using FIG. 10. Since the data signal 106 includes a guide pulse,
A guide pulse is created from the synchronization clock 105 (in this case, since the guide pulse is a pulse train of constant repetition,
It is obtained by dividing the synchronous clock based on a characteristic signal indicating the beginning of the data signal. ) When the recording clock for additional recording is reproduced by the exclusive OR of the guide pulse and the synchronization clock 105, the signal shown in FIG. 10C is obtained. Logical performance of this signal and data signal 106 yields additional recorded information (No. 11 107 (shown in FIG. 10d)).

Yet another embodiment will be described using FIG. 11. A signal 93 from the photodetector 80 is input to a digital signal detection circuit 86' to generate a signal φ1 and a synchronous clock φ6 corresponding to a) pit row for forming the guide groove. Here 2
The relationship between the two signals φ1 and φ6 on the time axis is shown in FIG. In this embodiment, when the repetition period of φ1 is T and that of φG is L, they are selected so as to satisfy the relationship T=6Xt. A method of creating a pulse train of φ6 from φ1 indicating the pitch 1 to the row of the guide groove by PLL is well known.4, φ6. The signal φ1 is inputted to the additional recording clock generator 88', and the signal φ4. Create a recording clock signal of φ5. The signal (data) of the information signal to be additionally recorded from the generator 91' is modulated by the modulation circuit 90' according to the recording clock, and this modulation signal 94' is input to the semiconductor laser opening circuit 92', and the laser of the semiconductor laser is Modulate the oscillation power.

The modulation method and modulation circuit 90' of this embodiment will be explained in detail. A preferred modulation method of the present invention is to encode data by treating it in units of m bits and converting it into recording bits of r) bits, and converting this to NRZI (or NRZ).
This is a combination that modulates with. Among them, 415MNRZ
An example will be described in which a device called I is used.

415 conversion is m=4. , n=5. This conversion table is shown in FIG. The configuration of the modulation circuit 90' is
A timing chart is shown in FIG. 173. Data is first stored in memory 200. Clock φ4
The data is read out according to the 4-bit register 20.
1 every period r. AND circuit 2 in Figure 14
03 and the OR circuit 204 performs the conversion shown in FIG. 12, which is latched into the 5-bit register 202. When read out in accordance with the clock φ5, a modulation signal 94' is formed.

A device for reproducing information recorded in the embodiment described in 1.f will be explained with reference to FIG. 15. In FIG. 15, the reproduced signal 100' is a digital signal (No. 4 converter 10
1', a pulse signal 105' whose phase is synchronized with the reproduced data signal 106' and the synchronization signal included in the reproduced signal is generated.

The means for generating the aforementioned signals 106' and 105' from the signal 100' will be explained. Since 415 conversion is performed, there is always at least one pit in the area other than the pit forming the guide groove, that is, in the area where additional information is recorded.

Therefore, since a periodic signal component exists in the reproduced signal, phase synchronization can be performed by the PLL so as to be synchronized with this period, and the signal 105' can be generated.

Further, as shown in FIG. 16, the pulse train φ1 corresponding to the pit forming the guide groove is formed using the aforementioned signal 105'. That is, in an apparatus for recording digital information such as the present invention, recording information is divided into blocks each consisting of a specific number of bits, and a signal indicating the division of the blocks is always inserted. Therefore, if the relationship of the signal φ1 indicating this division is set to a predetermined rule, the signal 105' can be changed to 176 by using the signal indicating the division.
If you divide the frequency into , you will get φ1.

When the signal corresponding to the pit forming the guide groove is removed from the reproduced signal 100' using the aforementioned φ1, the reproduced data signal 10 is obtained.
6' is obtained. The means for demodulating this reproduced data signal 106' will be further explained with reference to FIG.

Inputting the signal 105' to the demodulation clock generator 110,
Demodulated clock signal φ4. Generate φ5. Then, the reproduced data signal 106' is demodulated using the demodulation circuit 111 according to the signals φ4 and φ5 to obtain demodulated data.

The demodulation method will be explained using FIG. 17. The reproduced data signal 106' is taken into a 5-bit shift register 120 according to the signal φ5, and converted from a 5-bit pattern to a 4-bit pattern by a combination of an AND circuit 122 and an OR circuit 123, and then transferred to a 4-bit shift register 121.
is latched and read out every cycle T according to signal φ4.

[Brief explanation of the drawing]

1 to 5 are diagrams showing the configuration of an optical disc on which information is additionally recorded according to the present invention, and FIG. 6 is a diagram showing the configuration of an embodiment of the additional recording device according to the present invention. FIG. 7 is a time chart of signals for explaining the operation of the device shown in FIG. 6. Is Figure 8 an addition? FIG. 5 is a block diagram of an embodiment of the present invention, which is a device for reproducing signals from a disk that has been processed by Th. FIG. 9 is a diagram showing reproduction signals from an additionally recorded disc. 10th
The figure is a time chart when a signal is reproduced from an additionally recorded disc. FIG. 11 is a diagram showing the configuration of another embodiment of the present invention. FIG. 12 and FIG. 13 are diagrams for explaining the present invention in detail. FIG. 14 is a diagram showing the configuration of an embodiment of the main part of the present invention. FIG. 15 is a diagram showing the configuration of another embodiment of the present invention. FIG. 16 is a diagram for explaining the operation. FIG. 17 is a diagram showing the configuration of an embodiment of the main part of the present invention.

Claims (1)

[Claims] 1. A moving recording medium, in which guide pits are provided in advance on the recording surface in a meandering manner at a predetermined period and at predetermined intervals, and information recording sections are provided between the guide pits. A recording medium, a means for reading the guide pits from the moving recording medium, and generating a pulse corresponding to the guide pit from the read signal and dividing the space between the guide pits into a plurality of parts in synchronization with the pulse. means for generating a first clock; means for detecting a tracking signal based on the meandering of the guide pit from the read signal; A means for creating a second clock, and a means for dividing and encoding recorded information into a specific number of bits and converting it into NR.
means for creating a modulation signal for forming at least one information pit in the recording section between the guide pits from the Z-coded signal and the second clock; and controlling the position of the reading means using the tracking signal. An information processing device characterized by having means for. 2. The information processing device according to claim 1, wherein the guide pit has a round hole shape. 3. The information processing device according to claim 1 or 2, wherein the guide pit is provided in a phase type recording form. 4. The information processing device according to claim 1 or 2, wherein the guide pit is provided in a shading type recording form in which round holes are formed in a thin film forming the recording surface. . 5. The information processing device according to any one of claims 1 to 4, wherein the information pits are recorded in a shading type by making round holes in a thin film forming the recording surface. 6. The information processing device according to claim 5, wherein the guide pit and the information pit are different in size. 7. The information processing device according to any one of claims 1 to 6, wherein the period of the first clock is one integer fraction of the repetition period of the guide pit. 8. A moving recording medium, in which guide pits are provided in advance on the recording surface meandering at a predetermined period and at predetermined intervals, and at least one information pit exists in a recording section between the guide pits. a recording medium having information recorded as such, a means for reading out the guide pits and the information pits from the moving recording medium, and generating pulses corresponding to the guide pits and the information pits from the read signals; means for generating a first clock that divides the guide pit into a plurality of parts in synchronization with the pulse; means for detecting a tracking signal based on the meandering of the guide pit from the read signal; A second pulse that does not overlap with the pulse corresponding to the guide pit from the clock of
means for generating a clock; means for controlling the position of the reading means using the tracking signal; and means for demodulating the information pits recorded in the recording section between the guide pits based on the second clock. An information processing device comprising: 9. The information processing device according to claim 8, wherein the guide pit has a round hole shape. 10. Claim 8 or 9, characterized in that the guide pit is provided in a phase type recording form.
The information processing device described in section. 11. The information processing device according to claim 8 or 9, wherein the guide pit is provided in a shading type recording form in which round holes are formed in a thin film forming the recording surface. . 12. The information processing device according to any one of claims 8 to 11, wherein the information pits are recorded in a shading type by making circular holes in a thin film forming the recording surface. . 13. The information processing device according to claim 12, wherein the guide pit and the information pit are different in size. 14. The information processing device according to any one of claims 8 to 13, wherein the period of the first clock is one integer fraction of the repetition period of the guide pit.