JP3277513B2 - Optical information recording / reproducing method - 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 information recording / reproducing method for distinguishing a mask disk from a copy disk in an optical disk.

[0002]

2. Description of the Related Art An optical disk has a higher recording track density,
For reasons such as discrete partial writing and erasing, optically detectable guide tracks such as guide grooves are provided concentrically or spirally, and the recording layer formed on the guide tracks has a diameter of 1 μm or less. The recording is performed by irradiating the squeezed laser beam and drilling or causing changes in reflectance and transmittance. When recording digital information having a variable data length, a track is divided into a plurality of sectors in order to increase recording efficiency, and information is recorded and reproduced in units of about 512 bytes or 1 Kbyte. Each sector is composed of a sector index portion including a track address and sector address information, and a data field portion for recording and reproducing data.

On the other hand, when various defects, dusts, flaws, etc. are present on a base material, a recording film, a protective layer, etc. in an optical disk, a dropout occurs in a reproduced signal. Is as small as about 1 μm, the raw error rate is very poor, and there are many long burst-like dropouts. This burst-like dropout is often caused by a PLL (Pha) during reproduction.
se LockedLoop) operation.
When the oscillation frequency of L changes, a bit slip phenomenon occurs in which the number of self-reproduced clocks increases or decreases, and during data reproduction, word synchronization is shifted, and all subsequent sector data may become erroneous.

For this reason, when data is recorded on an optical disc, a means for inserting a resynchronization signal at regular intervals in sector data is usually employed. FIG. 3 shows an example of this format. In the sector data, one block (hereinafter referred to as a frame) is composed of a synchronization pull-in signal 50 for locking in the PLL, a resynchronization signal 51 for identifying the head of the data, and a data part 52, and m pieces of data are formed. One sector is composed of a frame. Data recording / reproduction is performed by detecting a sector identifier at the head of a sector and reading the address of a target sector. With such a configuration, even if the word synchronization of reproduction is deviated due to the bit slip phenomenon caused by a long dropout or the like as described above, the error is suppressed in a frame unit by the re-synchronization signal, and from the next frame, , Normal playback can be performed. In such a data format, when reproducing the data of the target sector, the reproduction circuit is activated by detecting the resynchronization signal from the reproduction signal, and the data of the target sector is reproduced. Further, when the resynchronization signal cannot be detected due to a defect of the disk or the like, the reproduction circuit is activated by detecting the resynchronization signal existing in the next frame.

Hereinafter, the operation of the reproducing method in the conventional optical information recording apparatus will be described with reference to FIG.

[0006] Data recorded on the optical disk 1 is irradiated by the laser 2 and read by the photodetector 3. Since the read reproduction signal is very small, the preamplifier 4
After amplifying the signal, the signal passes through a waveform equalizing circuit 5 for shaping the waveform, and then passes through a binarizing reproducing circuit 6 for binarizing the reproduced signal to become a binarized reproduced signal 100. The clock 10 is output from the binarized reproduction signal 100 by the PLL circuit 8.
1 is extracted. The clock 101 is sent to the address reproduction circuit 7. The address reproducing circuit 7 determines whether the address of each sector in the sector index portion, for example, the CRC of the track address and the sector address is normal, and then determines whether the address is the target address 106 set by the CPU 9 and then an address detection signal. 102 to CP
Notify U9. The CPU 9 checks the address detection signal 102 and outputs a demodulation control signal 104 for the target sector to the demodulation circuit 21. In the demodulation circuit 21, the PLL circuit 8 generates the clock 101 for the binarized reproduction signal 100 by itself, and executes the demodulation operation according to the clock. In the resynchronization signal detection circuit 23, the input binary reproduction signal 1
When the bit pattern of the resynchronization signal appears in 00,
Outputs resynchronization detection signal. The demodulation timing gate signal generation circuit 26 outputs a demodulation timing gate signal in frame units in accordance with these signals, and executes demodulation of one sector. The demodulated data is sent to the RAM control circuit 30 together with the RAM write gate signal, and the RAM 31
Is written to. The demodulated data of all frames is RA
When the data is written to M31 and the demodulation operation of one sector is completed, the error correction detection circuit 29 checks the demodulated data for errors, corrects any errors and generates correct data, and sends the data to the host computer 20.

Next, a bit slip detection circuit will be described. The resynchronization detection signal and the mask gate signal for masking the false resynchronization signal detection are ANDed by the AND gate 36, and the output is input to the clear terminal of the counter 32. The counter 32 receives the PLL clock 101 as a clock input, and when a reproduced clock for one frame is counted, the decoder 33 outputs a prediction signal to the position comparison circuit 34. In this position comparison circuit 34,
The resynchronization signal information generation circuit detects the presence or absence of bit slip reproduction by comparing the resynchronization detection signal and the predicted signal position within a window signal with a width of ± several bits with respect to the resynchronization detection signal output position. At 35, resynchronization information indicating the detection state of the resynchronization signal is generated and sent to the RAM control circuit 30.

[0008] The resynchronization information is stored in a RAM, for example, during demodulation.
The data is written in the demodulation data management area 31 and is used, for example, when an error cannot be corrected after error detection and correction, when the cause is a bit slip. Normally, a data reproduction gate is generated from the resynchronization signal, and data is stored in the buffer memory in frame units. However, when the resynchronization signal is not detected, for example, when the first resynchronization signal is not detected, data below the next detected resynchronization signal is not erroneously stored in the buffer memory area of the first frame. After confirming that an undetected frame has not been detected, the address of the buffer memory is forcibly set to the address where the data of the next frame should be stored so that the data of the next frame can be stored at a predetermined position. Change to (Reference: Application No. 1-182871)

[0009]

However, the above configuration has a problem that it is impossible to distinguish between master data and duplicated data.

The present invention solves the above-mentioned problems. When recording data, a resynchronization signal of an arbitrary frame is dropped or replaced, and at the time of reproduction, master data is copied or copied by detecting resynchronization signal detection information. It is an object of the present invention to provide an optical information recording / reproducing method capable of distinguishing between authenticated data and authenticated data.

[0011]

Means for Solving the Problems The present invention to achieve the above object, conversion example placed in different signal said plurality of resynchronization signal replacement means provided to the recording system, substituted again with the regeneration system
The different signal replaced by the synchronization signal detecting means by the replacing means.
Detecting a synchronization signal, with the arrangement determining means you determine the authenticity of the recording medium.

[0012]

According to the present invention, the above configuration discriminates whether the master data or the copied data is true or false.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An optical information recording / reproducing method according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a recording method of an optical information recording / reproducing method according to an embodiment of the present invention, and FIG. 2 is a block diagram showing a reproducing method.

1 and 2, 1 is an optical disk, 2 is a laser, 3 is a photodetector, 4 is a preamplifier, 5 is a waveform equalization circuit, 6 is a binarization reproduction circuit, 7 is an address reproduction circuit, 8 Is a PLL circuit, 9 is a CPU, 10 is a modulation circuit,
11 is a gate signal generation circuit, 12 is a synchronization pull-in generation circuit, 13 is a resynchronization signal generation circuit, 14 is a data generation circuit, 15 is a replacement resynchronization signal generation circuit, 16 is an AND circuit, 17 is a multiplex circuit, 18 is A laser drive circuit, 19 a parity generation circuit, 20 a host computer, 21 a demodulation circuit, 22 a shift register circuit, 23
Is a resynchronization signal detection circuit, 24 is a replacement resynchronization signal detection circuit, 25 is a prediction signal generation circuit, 26 is a gate signal generation circuit, 27 is a data reproduction circuit, 28 is a replacement resynchronization signal detection monitor circuit, and 29 is error correction. Circuit, 30 is a RAM control circuit, 31 is a RAM, 100 is a binarized reproduction signal, 101 is a clock, and 102 is an address detection signal.

The operation of the optical information recording / reproducing method having the above-described constituent blocks will be described below with reference to FIGS.

Incidentally, the optical disk 1, laser 2, photodetector 3, preamplifier 4, waveform equalizing circuit 5, binary reproducing circuit 6, address reproducing circuit 7, PLL circuit 8, CPU 9, 2
The digitized reproduction signal 100, clock 101, and address detection signal 102 are the same as those of the conventional example.

First, the recording operation will be described with reference to FIG. The CPU 9 controls the control signal 1 for the data recording operation.
03 is sent to the modulation circuit 10. In the modulation circuit 10, a gate signal is sent from the gate signal generation circuit 11 to the synchronization pull-in generation circuit 12, the resynchronization signal generation circuit 13, and the data generation circuit 14, respectively. To the data generation circuit 14, data obtained by adding a parity to the data transmitted from the host computer 20 by the parity generation circuit 19 is sent. Then, the data generated by each generation circuit is combined by the multiplex circuit 17 and sent to the laser drive circuit 18, where the data is recorded on the optical disk 1 via the laser 2.

On the other hand, the replacement resynchronization signal generation circuit 15
The resynchronization signal of a plurality of frames is replaced with a replacement resynchronization signal according to a command from the PU 9. When replaced, the resynchronization signal is sent from the gate signal generation circuit 11 to the AND circuit 1.
6 masked. In the present embodiment, the masking is performed at the output portion of the resynchronization signal generation circuit 13, but the gate signal itself of the resynchronization signal generation circuit 13 may be masked so that the resynchronization signal is not generated.

Next, the reproducing operation will be described with reference to FIG. The CPU 9 sends a demodulation control signal 104 to the demodulation circuit 21 for a data reproducing operation. In the demodulation circuit 21, 2
The value-reproduced signal 100 is subjected to serial-parallel conversion by the shift register circuit 22 in accordance with the clock 101, and signals are sent to the resynchronization signal detection circuit 23, the replacement resynchronization signal detection circuit 24, and the data reproduction circuit 27. Then, a prediction signal is generated by a prediction signal generation circuit 25, a gate signal for reproducing data is generated by a gate signal generation circuit 26, demodulated by a data reproduction circuit 27, and the demodulated data is written together with a RAM write gate signal. The data is sent to the RAM control circuit 30 and written to the RAM 31. The demodulated data of all the frames is written into the RAM 31, and when the demodulation operation of one sector is completed, the data is sent to the error correction circuit 29 and further sent to the host computer 20.

On the other hand, the number of the replacement resynchronization signals detected by the replacement resynchronization signal detection circuit 24 is counted by the replacement resynchronization signal detection monitor circuit 28, and if the number is less than a predetermined number preset by the CPU 9, the reproduction is performed. The data is determined to be copied data, and immediately, the gate signal generation circuit 2
6 and the control signal 105 to the error correction circuit 29,
The reproduction operation is stopped, and data is not sent to the host computer 20.

As described above, according to this embodiment, when the master data is copied and the copied data of the disk is reproduced, the detection of the replacement resynchronization signal signal is monitored so that the data can be read from the master disk. It is possible to judge whether the disc is a disc or a copied disc.

However, the method of replacing the resynchronization signal with the replacement resynchronization signal when recording the master data is possible only when a mastering disc is created, for example, when application software is recorded on the disc.

In this embodiment, an optical disk has been described as an example, but application to an optical card, an optical tape, and a magnetic recording medium is also possible.

[0025]

As is apparent from the above embodiment, according to the present invention, when data is recorded, the resynchronization signals of a plurality of frames are replaced, so that the master detects the resynchronization signals during reproduction, thereby detecting the master. It is possible to provide an optical information recording / reproducing method for discriminating whether the data is copied data or copied data.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a recording method of an optical information recording / reproducing method according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a reproducing method of an optical information recording / reproducing method according to one embodiment of the present invention.

FIG. 3 shows a format of a data field of an optical disc.

FIG. 4 is a block diagram showing a reproducing method of a conventional optical information recording / reproducing method.

[Explanation of symbols]

 9 CPU 11 Gate signal generation circuit 15 Replacement resynchronization signal generation circuit 16 AND circuit 24 Replacement resynchronization signal detection circuit 28 Replacement resynchronization signal detection monitor circuit

Claims (2)

(57) [Claims] 1. Synchronization pull-in signal, each destination of a plurality of data
A plurality of resynchronization signals arranged at the head and identifying the head;
The recording and reproducing device for a recording medium having a sector structure having a feed unit including a plurality of data, replacement means provided in the recording system replaces the different signals of the plurality of re-synchronization signals, provided in the reproducing system The replacement resynchronization signal detecting means is the replacement means.
In replacing the different re-synchronization signal is detected and the optical information recording and reproducing method determining means you determine the authenticity of the pre <br/> type recording medium. 2. The replacement means comprises: means for masking the resynchronization signal; and replacement resynchronization signal generation means for replacing the resynchronization signal with a replacement resynchronization signal in accordance with a command from a CPU. A replacement resynchronization signal detecting means for detecting a replacement resynchronization signal; and a true / false determination means for determining that the recording medium used is false when the number of the detected replacement resynchronization signals is equal to or less than a predetermined number set in the CPU. The optical information recording / reproducing method according to claim 1, comprising: