JP3454410B2 - Optical disk recording device, optical disk recording method, optical disk and optical disk reproducing device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc recording apparatus, an optical disc recording method and an optical disc, for example, a compact disc producing apparatus, a compact disc,
It can be applied to compact disc players. The present invention locally changes the reflective film of pits, marks, etc. at a timing that does not affect the edge position information, and does not affect the reproduction of the main data string by the pit string or the like. The sub data string can be recorded so as to be reproducible by an optical pickup for reproducing the main data column and difficult to copy by illegal copying.

[0002]

2. Description of the Related Art Conventionally, a compact disc has been subjected to EFM modulation (Eight modulation) after data processing of a data string to be recorded.
to fourteen modu- lation), a pit string having a period of 3T to 11T with respect to a predetermined basic period T is formed, whereby audio data and the like are recorded.

On the other hand, a recording area for management data is formed in the lead-in area on the inner peripheral side, and a desired performance or the like is selectively selected by the TOC (Table Of Contents) recorded in this recording area. It is designed to be playable.

The compact disc on which various data are recorded in this way is provided on the inner circumference side of the lead-in area.
Codes indicating the manufacturer, the place of manufacture, the disc number, etc. are engraved so that the history and the like of the compact disc can be visually confirmed.

[0005]

In such engraving, by confirming the history of the compact disc, it is considered that the illegal copy can be identified by the presence or absence of the engraving. However, this marking has a drawback that it is difficult to reproduce it with an optical pickup of a compact disc player for the purpose of visual confirmation. As a result, when the illegal copy is identified by the marking, a dedicated reproducing mechanism is eventually required to reproduce the marking.

The codes recorded by these methods can be duplicated by recording them in the same manner as ordinary pits, by peeling off the protective film and aluminum reflection film of the compact disc to form a stamper. , This caused a problem of illegal copying.

As a result, the reproduction of the audio data by the pit train is not affected at all, the reproduction is possible by the optical pickup for reproducing the audio data, and it is difficult to copy by the illegal copy, so that the sub information is recorded. If it can be recorded, it is considered that the illegal copy can be eliminated by using this second information.

The present invention has been made in consideration of the above points and can be reproduced by an optical pickup which reproduces data by the pit train without affecting the reproduction of the data by the pit train. In addition, it is an object of the present invention to propose an optical disk recording device, an optical disk recording method, and an optical disk created by these, which can record a sub data string that is difficult to copy by illegal copying.

[0009]

In order to solve such a problem, the present invention provides an optical disc recording apparatus and an optical disc recording method, wherein a sub data string for a pit and / or a land, or a mark and / or a space having a predetermined length or more. Based on the above, the sub-data string is recorded by locally changing the reflectance of the information recording surface at a position separated from the edge of the pit or mark by a predetermined distance.

Further, in the optical disc, the reflectance of the information recording surface is locally changed at a position separated from the edge of the pit or mark by a predetermined distance with respect to a pit and / or a land, or a mark and / or a space having a predetermined length or more. So that the sub data string is recorded.

When the reflectance of the information recording surface is locally changed at a position separated from the edge by a predetermined distance for a pit and / or a land, or a mark and / or a space having a predetermined length or more, the timing of the edge is changed. Can locally change the reflectance without any influence. As a result, the sub data string can be recorded by this change in reflectance, and the sub data string can be recorded without affecting the reproduction of the main data by the pit string or the like. Further, such a change in reflectance appears as a change in the amount of return light, so that the sub data string can be recorded so as to be reproducible by the optical pickup that reproduces the main data column such as the pit row. Further, the sub data string thus recorded can be copied only by a device having a recording system for recording the sub data string. In addition, depending on the method of peeling off the reflection film to create the stamper, copying becomes difficult. This makes it possible to record a sub data string, which is difficult to copy by illegal copying.

As a result, in the optical disc, the reflectance of the information recording surface is locally changed at a position separated by a predetermined distance from the edge of the pit or mark for a pit and / or land, or a mark and / or space having a predetermined length or more. Then, when the sub data string is recorded, the copy can be effectively excluded.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to the drawings as appropriate.

(1) First Embodiment (1-1) Configuration of the First Embodiment FIG. 2 is a time chart showing the format of a compact disc according to this embodiment together with the sectional structure of the compact disc. Is. This compact disc 1
(FIG. 2D), the disk substrate 2 is prepared by injection molding of polycarbonate or the like using a stamper as in the case of a normal compact disk. Here, in this injection molding, the disc substrate 2 is formed with fine irregularities corresponding to pits and lands on the information recording surface side. Further, the compact disc 1 is partially enlarged by an arrow a (FIG. 2E), and a reflective recording surface 3 for reflecting a laser beam is formed on the information recording surface side of the disc substrate 2 by vapor deposition, for example. Is formed, and then the reflective recording surface 3 is formed.
A protective film 4 for protecting the is formed.

As a result, the compact disc 1 can record an audio signal or the like by repeating the pits and lands, like the ordinary compact disc. Further, the compact disc 1 is transmitted through the disc substrate 2 and the laser beam L is reflected on the recording surface 3. By irradiating the light source and receiving the return light, the audio signal recorded in this way can be reproduced.

In the repetition of the pits and lands formed in this way, 75 CD frames are assigned per second as in the case of a normal compact disc (FIG. 2A), and each CD frame is allocated. 98 EFM frames are allocated to each (FIG. 2 (B)). Further, each EFM frame is divided into 588 channel clocks, of which the frame sync is assigned to the leading 22 channel clocks. The pits and lands are repeated with a length of an integral multiple of this basic cycle, with one cycle of this 1-channel clock as the basic cycle T.
In the frame sync, the reflective recording surface 3 is formed with the same period as that of the information recording surface of the CD-R. As a result, when the compact disc 1 is irradiated with the laser beam L with a predetermined light amount or more, the reflective recording surface 3 at the laser beam irradiation position is obtained.
Is configured to change reversibly, and this change in reflectance can be detected by a change in the amount of return light.

FIG. 1 is a block diagram showing a finishing apparatus for this compact disc. Compact disc 1
The disc identification code is recorded by the finishing device 10 before shipment.

That is, in this finishing apparatus 10, the spindle motor 11 is controlled by the servo circuit 12
The compact disc 1 is rotationally driven under the condition of constant linear velocity.

The optical pickup 13 irradiates the compact disc 1 with a laser beam, receives the return light, and outputs a reproduction signal RF whose signal level changes according to the amount of the return light. At this time, the optical pickup 13
By controlling the APC (Automatic Power Control) circuit 14, the light amount of the laser beam is raised at a predetermined timing, thereby locally changing the reflectance of the reflective recording surface 3 of the compact disc 1.

The amplifier circuit 15 amplifies the reproduction signal RF with a predetermined gain and outputs it. The binarization circuit 16 binarizes the reproduction signal output from the amplification circuit 15 with a predetermined reference level and outputs a binarized signal BD. PLL circuit 17
Reproduces the channel clock CK from the binarized signal BD.

The sync pattern detection circuit 18 detects a sync pattern repeatedly appearing in the binarized signal BD. That is, as shown in FIGS. 3A-1 to 3A-4 in comparison with FIG. 2, the binarized signal BD is the compact disc 1
The signal level is switched corresponding to the pit row formed in, and at the frame sync assigned to the beginning of each frame, after the signal level rises for the period 11T, the signal level continues for the period 11T. Get down. The synchronization pattern detection circuit 18 detects this frame sync by determining the continuous signal level of the binarized signal BD with the channel clock CK as a reference by the flip-flop circuits connected in multiple stages. Further, based on the detection result of the frame sync, a synchronization pattern detection pulse SY whose signal level rises during the period T of the beginning of each frame and one channel clock is output (FIG. 3 (C)).

The sync pattern prediction circuit 19 uses the sync pattern detection pulse SY as a reference to generate a channel clock CK.
A frame counter FP that outputs a frame pulse FP whose signal level rises during the period T of the beginning of each frame and one channel clock (FIG. 3 (C)). As a result, the synchronization pattern prediction circuit 19
Even when the sync pattern detection circuit 18 cannot correctly detect the frame sync due to a defect or the like, each frame sync is predicted and the frame pulse FP is output.

The disc identification code generation circuit 20 includes a subcode detection circuit 20A and a read only memory (RO).
M) 20B. Here, the subcode detection circuit 20A decodes the binarized signal BD to
The subcode information included in the binarized signal BD is reproduced.
Further, the disc identification code generating circuit 20 selectively outputs time information of minutes (AMIN) and seconds (ASEC) from the time information of minutes, seconds and frames included in the subcode information.

Here, the minutes (AMIN) and seconds (ASE)
The time information C) is subcode information defined in the standard of the compact disc 1 and indicates the position of data on the compact disc 1. That is, minutes (AMI
The time information of N) represents the data recorded on the compact disc 1 in minutes, for example, 0 to 7
It can take values up to 4. Further, the time information of seconds (ASEC) is a minute unit position defined by minutes (AMIN) and is further defined in seconds units, and takes a value from 0 to 59.

The read-only memory 20B holds the disc identification code ED, and outputs the held data by using the time information of the minute (AMIN) and the second (ASEC) output from the subcode detection circuit 20A as an address. Here, the disc identification code ED is ID information set as unique for each disc, information relating to the manufacturing plant, the manufacturing date,
It is composed of information for controlling whether copying is possible or not, and includes a synchronization signal indicating the beginning of the disc identification code, an error correction code, and the like. The read-only memory 20B holds the disk identification code ED by bit data and stores the minute (AMI
N), a 1-bit disc identification code ED is output for an address of 1 based on time information of seconds (ASEC).
As a result, the read-only memory 20B is
The bit disc identification code ED is output.

The modulation circuit 21 uses the disc identification code E.
The control signal MX of the APC circuit 14 is raised at a predetermined timing according to D, thereby instantaneously raising the light amount of the laser beam, and the reflectance of the compact disc 1 is locally changed.

That is, as shown in FIG. 4, the modulation circuit 21
In M, the M-sequence generation circuit 23 is composed of a plurality of cascade-connected flip-flops and an exclusive OR circuit, and the initial values of the plurality of flip-flops are set to these flip-flops at a timing corresponding to a change in time information of seconds (ASEC). After setting, the set contents are sequentially transferred in synchronization with the frame pulse FP, and are fed back between predetermined stages to generate M-sequence random number data MS in which logic 1 and logic 0 appear with equal probability. As a result, the M-sequence signal M
S is a series of pseudo-random numbers that repeats the same pattern in a cycle corresponding to 1 bit of the disc identification code ED.

The exclusive OR circuit 24 receives the M-sequence signal MS and the disc identification code ED and outputs this exclusive OR signal. That is, when the disc identification code ED is logic 0, the exclusive OR circuit 24 outputs an exclusive OR signal according to the logic level of the M-sequence signal MS, and conversely when the disc identification code ED is logic 1. , And outputs an exclusive OR signal obtained by inverting the logic level of the M-sequence signal MS. As a result, the exclusive OR circuit 24 modulates the disc identification code ED with the M-sequence random number.

The flip-flops 22A to 22P are connected in cascade, and the frame pulse FP is input to the first-stage flip-flop 22A. These flip-flops 22A
22P sequentially transfer this frame pulse FP in synchronization with the channel clock CK.

The OR circuit 25 includes the fifth-stage flip-flop 22 of the flip-flops 22A to 22P.
E and the final stage flip-flop 22P consisting of the 16th stage
And outputs the logical sum signals of these. As a result, the OR circuit 25 starts the frame sync,
When the period of 5 cycles of the channel clock CK elapses, the signal level rises by 1 channel clock period T, and when the frame sync starts and the period of 16 cycles of the channel clock CK elapses, the 1 channel clock period T Only the pulse signal WP whose signal level rises is output. Thus, the period during which the signal level of the pulse signal WP rises is the central 1-channel clock period T between the pits of the period 11T forming the sync pattern and the lands of the period 11T. It corresponds to a position that is separated from the edge by a sufficient distance.

The AND circuit 26 outputs a logical product signal of the exclusive OR signal output from the exclusive OR circuit 24 and this pulse signal WP as the light amount control signal MX of the APC circuit 14 (see FIG. D)).

The APC circuit 14 (FIG. 1) switches the light quantity of the laser beam from the light quantity at the time of reproduction to the light quantity at the time of recording according to the light quantity control signal MX. Here, the light amount at the time of recording is a light amount sufficient to change the reflectance of the reflective recording surface of the compact disc 1.

The system control circuit 28 is composed of a computer for controlling the operation of the finishing apparatus 10 as a whole. The optical pickup 13 is sought based on the subcode detected by the subcode detection circuit 20A, and the compact disc 1 is read. The above-mentioned disc identification code ED is recorded for a predetermined area.

As a result, the finishing device 10 causes the center of the pit having the period 11T for forming the sync pattern and the period 11T.
At the center of the land of T, the light quantity of the laser beam is raised according to the disc identification code ED modulated by the random number data MS, and the disc identification code ED is additionally recorded (FIGS. 3E-1 and 3E). -2)). Therefore, in the compact disc 1, when the disc identification code ED is not additionally recorded, the reproduction signal RF having a signal waveform saturated to a substantially constant value can be obtained in these pits and lands (see FIG. -1)), when the disc identification code ED is additionally recorded in this way, a reproduction signal RF in which the signal level locally changes in the vicinity of the center of the pit and the land according to the characteristics of the reflective recording surface 3. Is obtained (FIG. 3 (F-2)). Compact disc 1
The disc identification code ED is reproduced based on the change in the signal level of the reproduction signal RF.

FIG. 5 is a block diagram showing a compact disc player for reproducing the compact disc 1. In this compact disc player 30, the spindle motor 32 drives the compact disc 1 under the condition of constant linear velocity under the control of the servo circuit 33.

The optical pickup 34 irradiates the compact disc 1 with a laser beam, receives the return light, and outputs a reproduction signal RF whose signal level changes according to the amount of the return light. Here, the reproduction signal RF changes in signal level corresponding to the pits recorded on the compact disc 1. At this time, since the compact disc 1 is formed so that the reflectance is locally changed by recording the disc identification code ED, the signal level of the reproduction signal RF is equal to the disc identification code E.
It changes in accordance with the change in reflectance due to D. However, with respect to the pits and lands having a period of 11T, the reflectance is locally changed at a predetermined distance from the edges of the pits and lands, so that the signal level of the reproduction signal RF is 2 in these pits and lands.
The timing of crossing the reference level for value discrimination is maintained at the same timing as when the reflectance does not change at all.

With this, the binarization circuit 35 binarizes the reproduction signal RF at a predetermined reference level to create a binarization signal BD. Thus, since the local reflectance change in the compact disc 1 is at the center of the pit and the land of the period 11T, this local reflectance change is not detected in the binarized signal BD. Become.

The PLL circuit 36 operates on the basis of the binarized signal BD to reproduce the channel clock CCK of the reproduction signal RF.

The EFM demodulation circuit 37 reproduces reproduction data corresponding to the EFM modulation signal S2 by sequentially latching the binarized signal BD with the channel clock CCK as a reference. Further, the EFM demodulation circuit 37 performs EFM demodulation on the reproduced data, delimits the demodulated data in 8-bit units based on the frame sync, and deinterleaves the generated 8-bit unit signal to perform ECC (Error
Correcting Code) output to the circuit 38.

The ECC circuit 38 uses the EFM demodulation circuit 3
Based on the error correction code added to the output data of 7,
This output data is subjected to error correction processing, whereby the audio data D1 is reproduced and output.

Digital-analog conversion circuit (D / A) 3
Reference numeral 9 digital-analog converts the audio data D1 output from the ECC circuit 38 and outputs an audio signal S4 which is an analog signal. At this time, the digital-analog conversion circuit 39 is operated by the system control circuit 40.
When it is determined that the compact disc 1 is an illegal copy, the output of the audio signal S4 is stopped.

The system control circuit 40 is composed of a computer that controls the operation of the compact disc player 30. In advance, the system control circuit 40
The entire operation is controlled so as to access a predetermined area of the compact disc 1, and it is determined whether or not the compact disc 1 is an illegal copy based on the disc identification code ED output from the disc identification code reproduction circuit 41.
When it is determined that the copy is illegal, the output of the audio signal S4 from the digital-analog conversion circuit 39 is stopped and controlled.

The disc identification code reproduction circuit 41 decodes the disc identification code ED from the reproduction signal RF and outputs it.

FIG. 6 shows the disc identification code reproducing circuit 4
It is a block diagram which shows 1 in detail. In the disc identification code reproduction circuit 41, the synchronization pattern detection circuit 43
Detects the sync pattern by sequentially latching the binarized signal BD based on the channel clock CCK and determining the continuous logic level. Further, the synchronization pattern detection circuit 43 outputs a frame pulse FP whose signal level rises during the period T of the 1-channel clock at which each frame starts with the detected sync pattern as a reference.

The M-sequence generation circuit 45 initializes the address at a predetermined timing under the control of the system control circuit 40, and then sequentially advances the address by the frame pulse FP to access the built-in read-only memory. The M-series random number data MZ corresponding to the M-series random number data MS generated by the finishing device 10 is generated.

Analog-to-digital conversion circuit (A / D) 4
Reference numeral 7 performs analog-to-digital conversion processing on the reproduction signal RF with reference to the channel clock CCK, and outputs an 8-bit digital reproduction signal. Polarity inversion circuit (-1) 48
Outputs with the polarity of this digital reproduction signal inverted.

The selector 49 receives a digital reproduction signal directly input from the analog-digital conversion circuit 47 and a polarity inversion circuit 48 according to the logic level of the M-series random number data MZ output from the M-series generation circuit 45. Selectively outputs a digital reproduction signal with the polarity reversed. That is, when the M-series random number data MZ is logical 1, the selector 49 selects and outputs the directly input digital reproduction signal, and conversely, the M-series random number data is logical 0.
In the case of, the polarity-inverted digital reproduction signal is selected. As a result, the selector 49 reproduces the logic level of the disc identification code ED modulated by the M-series random number data MS by multi-valued data, and outputs the reproduction data RX by this multi-valued data.

The pit center detection circuit 50 is used in the finishing device 1.
Like the modulation circuit 21 in 0, 16
It is composed of flip-flops in stages and an OR circuit that receives predetermined outputs from these flip-flops. The pit center detection circuit 50 sequentially transfers the frame pulse FP by these flip-flops, and thereby the cycle 11T
The central portion detection signal CT whose signal level rises only for one channel clock period T is output at the center of the pit of 11 and the land of the period 11T.

The subcode detection circuit 51 monitors the binarized signal BD with the channel clock CCK as a reference and decodes the subcode information from the binarized signal BD. Further, the subcode detection circuit 51 monitors the time information of the decoded subcode information, and the 1-second detection pulse SE in which the signal level rises every time the time information changes by 1 second.
Output CP.

The adder 52 is a 16-bit digital adder, which reproduces the reproduction data RX and the accumulator (AC).
U) Output data AX of 53 is added and output. The accumulator 53 is composed of a 16-bit memory that holds the output data of the adder 52, and feeds back the held data to the adder 52, thereby forming an accumulator together with the adder 52. That is, the accumulator 53 clears the content held by the one-second detection pulse SECP, and then adds the adder 52 at the timing of the central portion detection signal CT.
Record the output data of. As a result, the adder 52 causes the reproduction data R reproduced by the selector 49 every second (between 7350 frames) of the time information based on the subcode information.
The logical value of X is accumulated and the accumulated value AX is output.

The binarization circuit 54 uses the 1-second detection pulse SEC.
At the timing when P rises, the output data AX of the accumulator 53 is binarized and output according to a predetermined reference value. As a result, the reproduction data RX of the disc identification code ED reproduced by the selector 49 is converted into the binary disc identification code ED.

The ECC circuit 55 performs error correction processing on the disc identification code ED with the error correction code added to the disc identification code ED and outputs it.

(1-2) Operation of the First Embodiment With the above configuration, in the manufacturing process of the compact disc 1 according to the present embodiment, a mother disc is created by an ordinary mastering device, and this mother disc is used. The disk substrate 2 is created by the created stamper. Further, the reflective recording surface 3 and the protective film 4 are formed on the disc substrate 2 to complete the compact disc 1 (FIG. 2). As a result, on the compact disc 1, pits and lands each having an integral multiple of the basic length corresponding to the predetermined basic period T are repeated, and a digital audio signal or the like is recorded.

At this time, in the compact disc 1, the same film structure as that of the information recording surface of the CD-R is applied to the reflection recording surface 3, so that when the laser beam L is irradiated with a predetermined light amount or more, the laser beam irradiation position The reflectance of the reflective recording surface 3 changes reversibly, and in addition to the main data recorded by repeating pits and lands, sub data can be additionally recorded.

In the finishing device 10 (FIG. 1), the compact disc 1 thus produced has a predetermined area reproduced under the control of the system control circuit 28, and the digital audio signal recorded by repeating the pits and lands is recorded. The disc identification code ED is recorded in this predetermined area so as not to affect the reproduction at all.

That is, in the finishing device 10, the reproduction signal RF obtained from the optical pickup 13 is converted into the binarization circuit 1.
6 is converted into a binarized signal BD, and the sync pattern detection circuit 18 detects a sync pattern from the binarized signal. As a result, of the pits and lands formed on the compact disc 1, the longest period 11
For T pits and lands, the start timing of these pits and lands is detected.

In the subsequent synchronization pattern predicting circuit 19, a frame pulse FP whose signal level rises at the timing of the start of the sync pattern is generated, and even if the binarized signal BD is not reproduced correctly due to a defect or the like, the frame pulse FP is generated at the correct timing. The start timing is detected for the pits and lands having a period of 11T.

Further, in the modulation circuit 21 (FIG. 4), the frame pulse F is generated by the flip-flops 22A to 22P.
P is sequentially transferred, and the outputs from the fifth and 16th-stage flip-flops are combined by the OR circuit 25, whereby the pits and lands having a period of 11T, the 1-channel clock period T at the center of the pit, the land The 1-channel clock period T of the central part of the is detected.

In conjunction with these, the subcode detection circuit 20
In A (FIG. 1), the subcode is reproduced, information identifying the reproduction position by the minute (AMIN) and the second (ASEC) is detected from the subcode, and these reproduction positions are specified by the subsequent read-only memory 20B. A disc identification code ED is output corresponding to the information. At this time, the read only memory 20B holds the disc identification code ED by the bit information, and the minute (AMIN) and the second (ASEC)
By outputting the disc identification code ED which is accessed and held by the information of 1., the disc identification code ED is outputted at an extremely low bit rate of 1 bit per second.

Further, in the M sequence generation circuit 23, M sequence random number data MS in which logic 1 and logic 0 are generated with equal probability is generated in synchronization with the frame pulse FP, and in the exclusive OR circuit 24, this M sequence is generated. Random number data M
The disc identification code ED is modulated by S. Further, in the AND circuit 26, the output of the exclusive OR circuit 24 is gated by the output of the OR circuit 25, whereby the pits and lands of the cycle 11T are generated according to the disc identification code ED modulated by the M-sequence random number data MS. Control signal MX whose signal level rises in each central part of
Is generated.

The compact disc 1 has the control signal M
The light quantity of the laser beam is raised by X, and the reflectance of the reflective recording surface 3 is locally changed.
A mark is locally formed at each central portion of the pit and land of T to form the disc identification code ED.

Such a mark is formed in the central portion of the pits and lands having a period of 11T, so that in the reproduced signal which changes depending on the pits and lands, the signals corresponding to the respective edges of these pits and lands. The level is held at the same signal level when the mark is formed and when no mark is formed. As a result, the disc identification code ED which is the sub data is recorded without affecting the reproduction of the main data by the pits and lands.

That is, assuming that the numerical aperture of the optical system for reproducing data by this kind of pit train is NA and the wavelength of the laser beam is λ, the diameter D1 represented by the following equation is set on the information recording surface of the compact disc 1. Light spots are formed. The diameter D1 is the half width at the light spot.

[0064]

[Equation 4]

Thus, if the mark is formed apart from the front and rear edges by the distance D1, the light spot becomes
The marks and edges will not be scanned at the same time. On the other hand, the edge position information is the timing at which the average level of the reproduction signal RF is set as a threshold value and the signal level of the reproduction signal RF crosses this threshold value. This timing is the center of the light spot. Corresponds to the timing when crosses the edge. At this timing, when the light beam does not irradiate the mark at the same time, the timing of crossing this threshold value is kept the same as that when no mark is formed.

As a result, if the diameter D1 of the equation (4) is halved and the mark is formed at a distance D1 at a distance D1 from the front and rear edges as shown in the following equation, the mark formed by the pits and the land Disc identification code E, which is sub-data, without affecting the reproduction of the data
D can be played.

[0067]

[Equation 5]

Here, a general numerical aperture NA in a compact disc player is 0.45 and a wavelength λ.
Is 0.78 [μm], so solving equation (5) gives D = 1.06 [μm]. Since the compact disc 1 rotates at a linear velocity of 1.2 [m / sec] and the frequency of the channel clock CK is 4.3218 [MHz], it is separated from the edge by a distance corresponding to four channel clock cycles. When the mark is formed, it means that the mark is formed at a distance D1 or more according to the equation (5), which is separated from the edge.

That is, from the edge of the pit and the land,
If the marks are formed with a distance corresponding to a period of 4T or more, the edge information of pits and lands similarly detected by the change in the amount of the returning light and the information by the marks can be reproduced separately. it can. As a result, the disc identification code ED which is the sub data is recorded without affecting the reproduction of the main data by the pits and lands.

At this time, the disc identification code ED is determined by the M-series random number data MS in which the logical 1 and the logical 0 appear with equal probability.
Of the reproduced signal R due to the change in reflectance by modulating
The change in F is observed like noise mixed in the reproduction signal RF, which makes it difficult to observe and find the disc identification code ED. Furthermore, copying the disc identification code ED can be made difficult.

In addition to these, the disc identification code E
By assigning 1 bit of D to the period of 1 second, that is, this 1 bit is 7350 in total (7350 = 75).
× 98) By recording the data dispersedly in the CD frame,
Even if the reproduction signal fluctuates due to noise or the like, the disc identification code ED can be reliably reproduced.

Further, in this way, the disc identification code E
In the compact disc 1 having D recorded therein, although the digital audio signal D1 by the pit train is copied by the conventional illegal copying method, it becomes difficult to copy the disc identification code ED.

That is, when an illegal copy is made in the same manner as the compact disc 1, the disc identification code E
Similarly, it is necessary to record D by marks, and it is necessary to prepare a disc-shaped recording medium in which the digital audio signal D1 is recorded in advance by a pit train and which has a reflective recording surface. It is also necessary to prepare a device having the same configuration as the finishing device 10. As a result, the disc identification code ED can be recorded with difficulty in copying.

That is, the compact disc 1 thus produced (FIG. 5) is a reproduction signal R whose signal level changes according to the amount of return light obtained by irradiating a laser beam in the compact disc player 30.
When F is detected, the signal level of the reproduction signal RF changes according to the pits and lands and the reflectance of the compact disc 1, and the reproduction signal RF is changed by the binarization circuit 35. It is binarized. Subsequently, the binarized signal BD is binarized by the EFM demodulation circuit 37, EFM demodulated and deinterleaved, and the ECC circuit 38 performs error correction processing, thereby reproducing the digital audio signal D1.

At this time, in the compact disc 1,
The marks whose local reflectances change locally are pits and lands with a period of 11T, and are located in the center of the pits and lands that are more than the distance corresponding to the period 4T from the edges (both front and rear edges). By being formed, the change in the signal level near each edge due to the formation of this mark is prevented, and thus even the compact disc 1 having the disc identification code ED recorded therein is correctly processed by a normal compact disc player. It becomes possible to reproduce.

In reproducing the digital audio signal D1 executed in this manner, the compact disc 1
Indicates that a predetermined area is accessed in advance, the disc identification code ED is reproduced from this area, and if the disc identification code ED cannot be reproduced correctly, the digital-analog conversion processing by the digital-analog conversion circuit 39 is stopped as an illegal copy. To be done.

That is, in reproducing the disc identification code ED (FIG. 6), in the compact disc 1, the sync pattern detection circuit 43 detects the frame sync, and the M sequence generation circuit 45 uses the detection of the frame sync as a reference. M-series random number data MZ corresponding to the M-series random number data MS at the time of recording is generated.

The reproduction signal RF is converted into a digital reproduction signal by the analog-digital conversion circuit 47, and this digital reproduction signal or a digital reproduction signal obtained by inverting the polarity is selected by the selector 49 based on the M-series random number data MZ. As a result, the reproduction data RX in which the logical level of the disc identification code ED is represented by multivalued data is reproduced.

In the compact disc 1, the reproduced data RX is accumulated by the accumulator 53 and the adder 52 in units of 1 second, thereby improving the SN ratio. Further, the accumulated result is binarized by the binarization circuit 54 to decode the disc identification code ED, and then error correction processing is performed by the ECC circuit 55 and output to the system control circuit 40.

(1-3) Effects of the First Embodiment According to the above configuration, the pits and lands of the sync pattern having a period of 11T are detected, and the pits and lands spaced from the edge by 4T or more are detected. By forming the mark in the center and recording the disc identification code, the reflection film of the pit and the land is locally changed at a timing that does not affect the edge position information, and the digital audio signal D1 is reproduced by the pit train. It is possible to record the disc identification code so as to be reproducible by an optical pickup which reproduces the digital audio signal D1 and difficult to copy by illegal copying without affecting the above.

Further, by recording the disc identification code by the mark for the pits and lands of the sync pattern which are regularly recorded, it is possible to easily record the disc identification code by utilizing this regularity.

Further, at this time, by allocating 1 bit of the disc identification code to the pits and lands of the sync pattern allotted for about 1 second and recording the disc identification code, the influence of noise and the like can be avoided and the disc identification code can be reproduced reliably. You can

Further, by modulating the disc identification code with M-series random number data and recording the disc identification code, it is possible to record the disc identification code with noise and it is difficult to find and analyze the disc identification code. Also during playback,
The disc identification code can be reproduced while effectively avoiding the influence of noise.

Further, by forming this mark with a length corresponding to the basic period T, similarly, the disc identification code can be recorded in a manner difficult to discriminate from noise, and the disc identification code can be made difficult to find and analyze.

Further, in the compact disc player, the signal level of the reproduction signal RF is detected, the disc identification code is decoded, the signal level is accumulated, and the influence of noise mixed in the disc identification code is removed, thereby eliminating noise. It is possible to reliably reproduce the disc identification code ED that is recorded with difficulty in identification.

In the selector 49, the digital reproduction signal is selectively processed by the M-series random number data MZ,
By reproducing the disc identification code, it is possible to reliably reproduce the disc identification code that is difficult to find and analyze.

(2) Second Embodiment FIG. 7 is a block diagram showing a finishing apparatus according to the second embodiment of the present invention. This finishing device 60 has a cycle of 9
Pits of T or more are detected and the disc identification code ED is recorded in these pits. In the structure shown in FIG. 7, the same structures as those of the finishing device 10 of FIG. 1 are designated by the corresponding reference numerals, and the duplicated description will be omitted.

That is, in the finishing device 60, the system control circuit 61 is composed of a computer for controlling the operation of the entire finishing device 60, and the reproduction signal RF.
The operation of the optical pickup 13 is controlled on the basis of the subcode detected by the disc code ED.
The area set as the recording area is sequentially traced twice by the optical pickup 13.

At this time, the system control circuit 61 holds the trace signal T1 at logic 0 in the first trace, whereas the system control circuit 61 continuously scans the portion scanned by the first trace in the second trace. In the trace,
Switch the trace signal T1 to logic one. Here, the first trace is for detecting pits with a period of 9T or more, and the second trace is for additionally recording a disc identification code in pits with a period of 9T or more based on the detection result. Is.

The pattern detection circuit 62 of 9T or more detects a pit having a period of 9T or more in the first trace by detecting a pulse width of 9T or more of the channel clock.

That is, as shown in FIG. 8, the pattern detection circuit 62 of 9T or more has 13 stages of flip-flops 64A to 64M connected in cascade, and the binary signal BD is provided in the first stage of these flip-flops 64A to 64M. input.
These flip-flops 64A to 64M sequentially transfer input data in synchronization with the channel clock CK.

The AND circuits 65A to 65C input the outputs of the flip-flops 64A to 64M, respectively, and output a logical product signal. At this time, the AND circuit 65A
First-stage, second-stage, twelfth-stage, and final-stage flip-flops 6
The outputs from 4A, 64B, 64L, and 64M are inverted when the logic level is input, and when the output of the logic "0011111111100" is obtained, that is, the logic level corresponding to the pit shape of length 9T. When is continuous, the logical level of the logical product signal is raised.

The subsequent AND circuit 65B includes first-stage, twelfth-stage, and last-stage flip-flops 64A, 64L, 64M.
For the output output from the above, the logical level is inverted and input, and the logical "001111111111"
When the output of "0" is obtained, that is, when the logic level corresponding to the pit shape having the length of 10T is continuous, the logic level of the logical product signal is raised.

The AND circuit 65C inverts the logic levels of the outputs from the first-stage and last-stage flip-flops 64A and 64M and inputs the outputs. When the output of the logic "0111111111110" is obtained, that is, When the logic level corresponding to the pit shape having a length of 11T is continuous, the logic level of the AND signal is raised.

The OR circuit 66 is an AND circuit 65A-65.
By calculating the logical sum of the output signals output from C, when any of the pits in the periods 9T, 10T, and 11T is detected, the logical sum signal MD that becomes logical "1" is output. The flip-flop 67 receives the logical sum signal MD.
Is sampled with the channel clock CK and waveform shaping is performed to remove the influence of glitch noise and the like, and the detection pulse NP is output.

The pattern predicting circuit 63 of 9T or more switches its operation in accordance with the logic level of the trace signal T1 output from the system control circuit 61, so that in the first trace, the position of pits with a period of 9T or more is changed. While the information is recorded, in the second trace, the timing signal EP for recording the disc identification code is output based on the recorded position information.

That is, as shown in FIG. 9, in the 9T or more pattern prediction circuit 63, the subcode detection circuit 69
Is a binarized signal B based on the channel clock CK.
By processing D, the position information (frame (AF (AF)
RAME), seconds (ASEC), minutes (AMIN)). Here, the frame (AFRAME) is 7 for 1 second.
The position information is divided into five equal parts. Further, the subcode detection circuit 69 decodes the S0 flag (consisting of the subcoding synchronization pattern) included in the subcode and outputs it as a subcode flag S0FLAG indicating one frame of the subcode.

The synchronization pattern detection circuit 70 detects a sync frame by monitoring the continuous logic level of the binarized signal BD with the channel clock CK as a reference, and the signal level rises at the start timing of each frame. The sync frame detection signal SY is output.

The sync pattern prediction circuit 71 is composed of a ring counter which counts the channel clock with reference to the sync frame detection signal SY, so that even if a sync frame is not detected by the sync pattern detection circuit 70 due to a defect or the like, A frame pulse FP without any loss is transmitted by utilizing the sync frame periodicity.

The counter 72 is composed of a ring counter which counts up the channel clock CK with reference to the frame pulse FP, whereby one EF is provided.
A count value EFMC including position information that divides M frames into 588 is output. Further counter 72
Counts up the frame pulse FP with reference to the subcode flag S0FLAG, so that the CD of 1
Count value CD consisting of position information that divides the frame into 98 equal parts
Create C.

In this way, the count values EFMC, CD
When outputting C, the counter 72 causes the trace signal T1
Is logical 0 (that is, in the case of the first trace), the continuous channel clock CK is counted up so that the count value EFMC becomes 0 at the timing when the frame pulse FP rises, whereas the trace signal T1 Is logic 1 (that is, in the case of the second trace), the continuous channel clock CK is counted up so that the count value EFMC becomes 7 at the timing when the frame pulse FP rises.

Here, for seven cycles of the channel clock CK corresponding to this value 7, the timing signal EP is output by the count value EFMC to the laser beam irradiation position specified by the count value EFMC, and the light quantity of the laser beam is output. Corresponds to the delay time until rises.
As a result, the counter 72 counts up the channel clock CK so that the count value EFMC advances by the delay time in the second trace.

The memory 74 stores position information (frame (AFRAME), second (ASE) by the subcode detection circuit 69.
C), minute (AMIN)), a count value EFMC, which is position information by the counter 72, and a memory for recording the detection pulse NP using the CDC as an address, and the operation is switched according to the trace signal T1. That is, when the trace signal T1 is logic 0 (that is, in the case of the first trace), the memory 74 records the detection pulse NP output from the pattern detection circuit 62 for 9T or more by using the position information as an address. On the other hand, when the trace signal T1 is logic 1 (that is, in the case of the second trace), the memory 74 outputs the content held with these position information as addresses as the timing signal EP.

The modulation circuit 75 is constructed similarly to the modulation circuit 21 described above with reference to FIG. That is, the modulation circuit 7
5, a predetermined number of flip-flops are connected in cascade, and these flip-flops sequentially transfer the frame pulse FP at a channel clock cycle. Further modulation circuit 7
5 receives an output from a predetermined number of these flip-flops, so that in a pit having a period of 9T or more, when a period of 4T elapses from the start edge of this pit, a timing signal whose logic level rises by the period T of one channel clock To generate.

Further, the modulation circuit 75 uses the timing signal E
M-sequence random number data is generated based on P, and the disc identification code ED is modulated by this random number data. Further, this modulation result is gated by the timing signal generated by the flip-flop and output as the control signal MX.

As a result, the finishing device 60 records the disc identification code for the pits having a period of 9T or more which satisfy the condition described in the equation (5).

That is, in a pit having a period of 9T or more, even if the reflectance is changed by a period of 1T while being separated from the start edge by a period of 4T, the reflectance is changed without affecting the positional information of the front and rear edges. Can be made. In addition, for pits with a cycle of 9T or more, cycle 1
It is characterized by a higher occurrence frequency than 1T pits and lands. As a result, one bit of the disc identification code can be recorded in many pits, and the reliability of the disc identification code can be improved accordingly.

Thus, when reproducing the compact disc according to this embodiment, a pattern detection circuit having the same configuration as the 9T or more pattern detection circuit 62 applied to the finishing device 60 detects pits of 9T or more. The disc identification code is reproduced by detecting the signal level of the reproduction signal RF for this pit.

According to the configuration of the second embodiment, the period 9
Even if the pits of T or more are detected and the disc identification code is recorded by locally changing the reflectance of the information recording surface at a timing separated from the edge of the pits by a predetermined distance, the first embodiment is also possible. The same effect as can be obtained. Further, as compared with the first embodiment, it is possible to record the disc identification code by using pits having a high occurrence frequency,
The disc identification code can be recorded reliably for that amount,
If necessary, the time allocated to 1 bit of the disc identification code can be shortened to improve the recording density of the disc identification code.

(3) Third Embodiment FIG. 10 is a block diagram showing a finishing device for a compact disc 1 according to a third embodiment. In this finishing device 80, pit detection processing with a period of 9T or more,
The additional recording process of the disc identification code is simultaneously executed in parallel. In the structure shown in FIG. 10, the same structures as those of the finishing device 60 described above with reference to FIG. 7 are designated by the corresponding reference numerals, and the duplicated description will be omitted.

That is, in this embodiment, the finishing device 80 has the optical pickup 83A for read-ahead.
And a recording optical pickup 83B which scans the scanning locus scanned by the preceding read optical pickup 83A with a delay of a predetermined time.

As a result, the finishing device 80 causes the reproduction signal RF obtained from the optical pickup 83A for preceding reading.
Are processed to detect pits having a period of 9T or more, and the disc identification code ED is recorded by the recording optical pickup 83B which follows based on the detection result.

That is, the finishing device 80 outputs the detection result NP of the pattern detection circuit 62 of 9T or more to the FIFO memory 84.
To the modulation circuit 75, the delay time until the recording optical pickup 83B scans the scanning locus scanned by the preceding read optical pickup 83A is compensated.

The system control circuit 82 is composed of a computer which controls the operation of the finishing device 80, and causes the optical pickups 83A and 83B to seek the recording position of the disc identification code.

According to the configuration shown in FIG. 10, the pit detection processing with a period of 9T or more and the additional recording processing of the disc identification code are simultaneously executed in parallel, thereby obtaining the same effect as that of the second embodiment. In addition, the time required for processing can be shortened.

(4) Other Embodiments In the above-mentioned embodiments, the CD-recording is performed on the reflective recording surface.
Although the case where the film structure of the ROM is applied has been described, the present invention is not limited to this, and for example, the film structure of the phase change optical disk may be applied.

Further, in the above-described first embodiment,
When the reflectance of the information recording surface is locally changed with a period of 5T or more from the pit edge, in the second and third embodiments, the information recording surface of the information recording surface is spaced with a period of 4T or more from the pit edge. When changing the reflectance locally,
However, the present invention is not limited to this, and the same effect can be obtained even if the reflectance of the information recording surface is locally changed at a period of 3T or more from the edge of the pit.

That is, when the reflectance of the information recording surface is locally changed in the vicinity of the edge of the pit, jitter will occur in the reproduced signal. However, in an actual compact disc player, even if a slight amount of jitter occurs in the reproduction signal from the pit, it is possible to reproduce the data in the pit train without any problem.

In relation to this jitter, for example, in the EFM system used for modulation of a compact disc,
The minimum inversion interval is 3 channel clock. This minimum inversion interval is defined as a distance at which, even if a pit change such as a reflectance change occurs at a position separated from the edge of the pit by this minimum inversion interval, the occurrence of jitter due to the change can be almost ignored. . As a result, if the disc identification code ED is additionally recorded at a position more than the minimum inversion interval from the edge of the pit, the deterioration of the jitter due to the disc identification code ED can be maintained at a sufficiently small value, and the data by the pit string can be reliably reproduced. can do. Therefore, for example, in the case of a compact disc, it is possible to record the disc identification code by locally changing the reflectance at a distance corresponding to the three-channel clock from the edge of the pit.

When the disc identification code is recorded at a distance corresponding to the 3-channel clock from the edge of the pit, the disc identification code can be recorded in the pits and lands having a period of 7T or more.

In the second and third embodiments described above, the case where the disc identification code is recorded in the pits having a period of 9T or more has been described, but the present invention is not limited to this.
You may make it record on a pit and a land with a period of 9T or more.

Further, in the above-described second and third embodiments, the case where the disc identification code is recorded in the pit having a period of 9T or more at a distance of 4T from the edge on the pit start side has been described. The invention is not limited to this, and may be recorded in the center of each pit having a period of 9T or more.

Further, in the above-described first embodiment,
The case where the disc identification code is recorded in the predictable sync frame portion has been described, but the present invention is not limited to this.
It can be applied to any signal as long as it is possible to predict the signal to appear in advance. For example, if all or part of the signal recorded on the compact disc is known, it is possible to predict the pit train on the disc. Even in such a case, the present method is applied to predict a position sufficiently far from the edge portion of the pit, and the laser output is momentarily increased at the predicted position, so that the disc identification code ED Can be additionally recorded.

Further, in the above-described embodiments, the case where the reflectance of the information recording surface is locally changed only for one channel clock cycle in the pits and lands having a predetermined length or more has been described, but the present invention is not limited to this. Not limited to this, if the reflectance is partially changed at a predetermined distance from the front edge and the rear edge, the disc identification code can be recorded without losing the edge information. And for land, the central cycle 3
The reflectance may be changed by the amount of T.

Further, in the above embodiments, the case where the disc identification code is recorded has been described, but the present invention is not limited to this, and a digital audio signal encrypted by the pit and the land length is recorded, and this encryption is performed. When recording the key information necessary for canceling the key, or when recording the data necessary for selecting and decrypting the key information, various data necessary for canceling the encryption may be recorded.

In the above-described embodiments, the case where the disc identification code is recorded in the compact disc finishing apparatus has been described, but the present invention is not limited to this, and is applied to a compact disc player, for example, a pit row. The number of times data is reproduced and the number of times data is copied may be recorded by.

Further, in the above-mentioned embodiment, the case where the cumulative value by the accumulator is binary-coded to reproduce the sub data string composed of the disc identification code has been described, but the present invention is not limited to this, and the cumulative value is accumulated. The value may be multivalued to reproduce the sub data string.

In the above embodiment, the EFM is used.
Although the case where the digital audio signal is modulated and recorded is described, the present invention is not limited to this, and 1-7 modulation, 8
It can be widely applied to various modulations such as -16 and 2-7 modulations.

Further, in the above-mentioned embodiments, the case where desired data is recorded by pits and lands has been described, but the present invention is not limited to this, and is widely applicable to the case where desired data is recorded by marks and spaces. Can be applied.

Further, in the above-mentioned embodiment, the case where the present invention is applied to the compact disc and its peripheral device to record the audio signal has been described, but the present invention is not limited to this, and various types such as a video disc and the like are described. It can be widely applied to optical disks and their peripheral devices.

[0131]

As described above, according to the present invention, by mainly changing the reflective film of pits, marks, etc. at a timing that does not affect the edge position information, the main data due to the pit row etc. The sub-data string can be recorded without affecting the reproduction of the string, and can be reproduced by an optical pickup that reproduces the main data string and difficult to copy by illegal copying.

[Brief description of drawings]

FIG. 1 is a block diagram showing a compact disc finishing apparatus according to a first embodiment of the present invention.

2A and 2B are a sectional view and a time chart used for explaining a compact disc to be finished by the finishing device in FIG.

FIG. 3 is a time chart used to explain the operation of the finishing apparatus shown in FIG.

4 is a block diagram showing a modulation circuit of the finishing device of FIG. 1. FIG.

5 is a block diagram showing a compact disc player for reproducing a compact disc created by the finishing device of FIG. 1. FIG.

6 is a block diagram showing a disc identification code reproducing circuit of the compact disc player of FIG. 5. FIG.

FIG. 7 is a block diagram showing a compact disc finishing apparatus according to a second embodiment of the present invention.

8 is a block diagram showing a 9T or higher pattern detection circuit of the finishing apparatus of FIG. 7. FIG.

9 is a block diagram showing a 9T or higher pattern prediction circuit of the finishing device of FIG. 7. FIG.

FIG. 10 is a block diagram showing a compact disc finishing apparatus according to a third embodiment of the present invention.

[Explanation of symbols]

1 ... Compact disc, 2 ... disc substrate, 3 ...
... Reflective recording surface, 4 ... Protective film, 10, 60, 80 ... Finishing device, 13, 83A, 83B ... Optical pickup,
14 ... APC circuit, 18, 41, 70 ... Sync pattern detection circuit, 19, 71 ... Sync pattern prediction circuit, 2
0 ... Disc identification code generation circuit, 20A, 51, 69
...... Subcode detection circuit, 21, 75 ...... Modulation circuit, 3
0 ... Compact disc player, 41 ... Disc identification code reproduction circuit, 62 ... 9T or higher pattern detection circuit, 63 ... 9T or higher pattern prediction circuit,

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) G11B 7/0045 G11B 20/10

Claims (35)

(57) [Claims] 1. A light beam for a disc-shaped recording medium in which pits and lands or marks and spaces having a length corresponding to a main data train are repeated on an information recording surface to record the main data train in advance. Light pick up
And the pits and / or lands, or the marks and / or spaces having a predetermined length or more, are separated by a predetermined distance from the edge of the pits or marks recorded on the information recording surface based on the sub data string. in places, by changing the reflectance locally the information recording surface, recording means additionally records the data sequence of the sub to the disc-shaped recording medium
Optical disk recording apparatus characterized by comprising and. 2. The one bit of the sub data string is repeatedly recorded in a plurality of the pits and / or lands, or the marks and / or spaces.
The optical disk recording device described in 1. 3. The sub data string is locally changed in accordance with the data string obtained by modulating the sub data string with an M-series random number to thereby change the sub data string to the disc. The optical disc recording apparatus according to claim 1, wherein the optical disc recording apparatus records on a flat recording medium. 4. The optical disk recording apparatus according to claim 1, wherein the predetermined distance is a distance D represented by the following equation. [Equation 1] Here, NA is the numerical aperture of the optical system that reproduces the main data string, and λ is the wavelength of the light beam applied to the optical system. 5. The predetermined distance is the shortest length of the pits and lands or the marks and spaces formed on the disk-shaped recording medium. Optical disc recording device. 6. The optical disk recording apparatus according to claim 1, wherein the sub-data string is an identification data string for identifying the disk-shaped recording medium. 7. The main data string is an encrypted data string, and the sub data string is a data string required for decryption of the main data string. The optical disk recording device according to claim 1. 8. The optical disk recording apparatus according to claim 1, wherein the sub data string is data of the number of times of reproduction of the main data string. 9. The optical disk recording apparatus according to claim 1, wherein the sub-data string is data of the number of times of copying the main data string. 10. Detecting means for detecting pits and / or lands or marks and / or spaces having a predetermined length or more based on return light obtained by irradiating a light beam, and outputting a detection result, and the detection means. Storage means for temporarily holding the result, control means for scanning the light beam on pits and / or lands, or marks and / or spaces corresponding to the detection result held in the storage means, and the detection held in the storage means 7. A light amount switching means for temporarily raising the light amount of the light beam and locally changing the reflectance of the information recording surface based on the result and the sub data string. 1. The optical disk recording device described in 1. 11. A first optical system for irradiating the disk-shaped recording medium with a first light beam, receiving return light, and outputting a light reception result.
An optical system, a detection unit that detects a pit and / or a land, or a mark and / or a space having a predetermined length or more based on the light reception result, and outputs a detection result; The second light beam is irradiated onto the disk-shaped recording medium after the first light beam, and the light amount of the second light beam is temporarily changed based on the detection result and the sub data string. The optical disc recording apparatus according to claim 1, further comprising a second optical system that is started up and locally changes the reflectance of the information recording surface. 12. The light beam irradiated to the pits and the disk-shaped recording medium in which data of the main repeated the land or the marks and spaces the information recording surface is recorded in advance by a length corresponding to the main data string, Regarding the pits and / or lands having a predetermined length or more, or the marks and / or spaces, at a position separated by a predetermined distance from the edge of the pits or marks recorded on the information recording surface based on the sub data string, An optical disc recording method, wherein the reflectance of the information recording surface is locally changed to additionally record the sub data string on the disc-shaped recording medium. 13. The optical disk recording method according to claim 12, wherein one bit of the sub data string is repeatedly recorded in a plurality of the pits and / or lands, or the marks and / or spaces. 14. The sub-data string is locally changed in accordance with the data string obtained by modulating the sub-data string with an M-series random number, so that the sub-data string is recorded on the disc. The optical disc recording method according to claim 12, wherein the optical disc recording is performed on a flat recording medium. 15. The optical disk recording method according to claim 12, wherein the predetermined distance is a distance D represented by the following equation. [Equation 2] Here, NA is the numerical aperture of the optical system that reproduces the main data string, and λ is the wavelength of the light beam applied to the optical system. 16. The predetermined distance is the shortest length of the pits and lands or the marks and spaces formed on the disk-shaped recording medium. Optical disc recording method. 17. The optical disk recording method according to claim 12, wherein the sub data string is an identification data string for identifying the disk-shaped recording medium. 18. The main data string is an encrypted data string, and the sub data string is a data string necessary for decryption of the main data string. The optical disc recording method according to claim 12. 19. The optical disc recording method according to claim 12, wherein the sub data string is data of the number of times of reproduction of the main data string. 20. The optical disk recording method according to claim 12, wherein the sub-data string is data of the number of times of copying the main data string. 21. A pit and / or a land, or a mark and / or a space having a predetermined length or more is detected based on a return light obtained by irradiating a light beam, and a pit having a predetermined length or more is detected from the detection result. And / or predicting the timing at which the light beam scans the land, or the mark and / or the space, and based on the prediction result and the sub data string, temporarily raises the light amount of the light beam to locally 13. The reflectance of the information recording surface is changed.
The optical disc recording method described in. 22. A pit and / or a land, or a mark and / or a space having a predetermined length or more is detected based on a return light obtained by irradiating a light beam, the detection result is temporarily held, and the same portion is re-displayed Scanning, based on the detection result and the sub-data string temporarily held, the light amount of the light beam is temporarily raised to locally change the reflectance of the information recording surface. The optical disc recording method according to claim 12. 23. The disc-shaped recording medium is irradiated with a set of light beams, and based on the reproduction result by the preceding light beams, the light amount of the following light beams is temporarily raised to locally perform the information. The optical disc recording method according to claim 12, wherein the reflectance of the recording surface is changed. 24. The pits and lands or the marks and spaces having a length corresponding to the main data string are previously repeated on the information recording surface to record the main data string, and the pits and / or lands having a predetermined length or more. Alternatively, with respect to the mark and / or the space, a part where the reflectance of the information recording surface is locally changed is formed at a position separated from the edge of the pit or the mark by a predetermined distance.
An optical disc in which a sub data string is additionally recorded. 25. The optical disk according to claim 24, wherein one bit of the sub data string is repeatedly recorded in a plurality of the pits and / or lands, or the marks and / or spaces. 26. The optical disc according to claim 24, wherein the sub-data string is modulated by an M-series random number and recorded. 27. The optical disc according to claim 24, wherein the predetermined distance is a distance D represented by the following equation. [Equation 3] Here, NA is the numerical aperture of the optical system that reproduces the main data string, and λ is the wavelength of the light beam applied to the optical system. 28. The optical disc according to claim 24, wherein the predetermined distance is the shortest length of the pits and lands, or the marks and spaces. 29. The optical disc according to claim 24, wherein the sub data sequence is an identification data sequence for identifying an optical disc. 30. The main data string is an encrypted data string, and the sub data string is a data string necessary for decryption of the main data string. The optical disc according to claim 24. 31. The optical disc according to claim 24, wherein the sub data string is data of the number of times of reproduction of the main data string. 32. The optical disc according to claim 24, wherein the sub-data string is data of the number of times of copying the main data string. 33. An optical disk is irradiated with a laser beam,
In an optical disc reproducing apparatus for reproducing data recorded on the optical disc by returning light of the optical disc, the optical disc has pits and lands or marks and spaces having a length corresponding to a main data string repeated on an information recording surface. The main data string is recorded in advance , and the information is locally recorded at a position separated from the edge of the pit or mark by a predetermined distance for the pit and / or land or the mark and / or space having a predetermined length or more. The part where the reflectance of the surface changes is formed.
And a sub-data string is additionally recorded, and the optical disc reproducing apparatus includes a light receiving unit that receives the return light and outputs a light receiving result, a binarizing unit that binarizes the light receiving result, and the binary value. A main decoding means for processing the output signal of the converting means to reproduce the main data sequence; a sub decoding means for reproducing the sub data sequence based on the signal level of the light reception result; 6. An optical disk reproducing apparatus, comprising: a control unit that controls the output of the main data string by the main decoding unit according to the sub data string reproduced by the decoding unit. 34. The sub-decoding means comprises: an M-sequence generating means for generating a predetermined M-sequence; a calculating means for calculating the received light result and the M-sequence; and a calculating means for a predetermined integration period. 4. An integration means for integrating the calculation result of 1. and an identification means for identifying the integration result of the integration means and outputting the sub data string.
3. The optical disk reproducing device described in 3. 35. The optical disk reproducing apparatus according to claim 34, wherein the sub-decoding means performs error correction processing on the sub-data string output from the identifying means, and outputs the error-corrected data.