JP2001167510A - Optical disc determination method and optical disc apparatus - Google Patents

Abstract

(57) [Summary] [Problem] To easily determine whether or not an optical disc has a large recording capacity. A signal recorded on an optical disk is read by rotating the optical disk at a desired speed and position. When the optical disk is a read-only optical disk, the control unit 50 detects the frequency of the clock CKRF of the reproduction signal. This is because the clock frequency differs between the standard density optical disc and the high density optical disc. For example, when the recording density is twice the standard density,
The clock frequency in the high-density optical disk is 1.4 times. As another determination method, the optical disk is determined based on the magnitude of the burst error signal based on the difference in the unit delay amount during the interleave processing. When the optical disk is of the writable type, the frequency of the wobble signal or the error correction result of the cyclic code is detected to easily and reliably determine whether the optical disk is of standard density or high density. Can be determined. Its configuration is also simple.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an optical disk discriminating method and an optical disk device. Specifically, when the optical disk is rotated at a desired speed and position to read a signal, and when the optical disk is a read-only optical disk, the clock of the obtained signal or
By using an error signal based on the difference in the unit delay during the deinterleaving process, it is possible to distinguish an optical disk recorded at a standard density from an optical disk recorded at a higher density than the standard density.

When an optical disk is a writable disk, whether the wobble signal has a frequency output or not, an error determination output of a cyclic code is used, and an optical disk recorded at a standard density is recorded at a higher density than the standard density. It is possible to discriminate the optical disk from which data has been written.

[0003]

2. Description of the Related Art In recent years, demands for increasing the capacity of recording media have been increasing. In order to increase the recording density of optical discs, methods such as narrowing the track pitch and shortening the minimum length of recording pits have been proposed. ing.

Here, an optical disk satisfying the compact disk standard, for example, a write-once optical disk (CD-R) or a rewritable optical disk (CD-RW) standardized by ISO / IEC13490-1 (hereinafter referred to as these). Are collectively referred to as writable optical disks) and the like, and it is desired to increase the recording capacity so that more data can be recorded.

[0005]

When the recording capacity of a write-once optical disc such as a write-once type or a rewritable type is increased as described above, an optical disc apparatus for recording / reproducing a signal has a large recording capacity. If it is not possible to quickly and easily determine whether an optical disk has a large capacity (high-density optical disk) or a conventional recording capacity optical disk (standard density optical disk), Recording / reproduction operation cannot be performed. For example, before demodulating data recorded on a disc,
If it is not possible to determine whether or not the optical disk is a high-density optical disk, it is not possible to perform processing unique to the high-density optical disk and selection of dedicated hardware.

In an optical disk (blank disk) on which no data is recorded, data indicating the type of the optical disk is recorded since discrimination cannot be performed using recorded data. However, in such a case, the discrimination process cannot be performed on an optical disk already on the market.

Accordingly, the present invention provides an optical disk and an optical disk apparatus that can easily determine whether or not the optical disk has an increased recording capacity, including an existing optical disk. .

[0008]

According to the optical disk discriminating method of the present invention, when the optical disk is read-only, the standard density is determined by the number of clocks extracted from the reproduction signal reproduced from the optical pickup. It is characterized in that it is determined whether the optical disk is recorded on the optical disk or the optical disk is recorded at a density higher than the standard density.

In the optical disk apparatus according to the present invention, a clock generation / servo control unit to which a reproduction signal output from the optical pickup is supplied and a clock output from the clock generation / servo control unit are used. The clock generation / servo control unit includes an edge detector of the binarized reproduction signal, and a clock generation unit generated based on the edge output. The clock output from the clock generation unit is supplied to the control unit, and whether the optical disk is recorded at the standard density or the optical disk recorded at a higher density than the standard density is determined based on the number of clocks per unit time. It is characterized by doing so.

According to a fourth aspect of the present invention, there is provided an optical disk discriminating method according to the present invention, wherein the unit delay amount at the time of interleave processing of a signal to be recorded is a signal recorded at a standard density. When the difference between a signal recorded at a higher density than the standard density and an error after decoding due to the difference in the unit delay, the optical disc of the standard density recording and the optical disc of the high density recording are considered. Is determined.

In the optical disk apparatus according to the present invention, the unit delay amount at the time of the interleave processing of the signal to be recorded is the same as the signal recorded at the standard density,
An optical disc device for a read-only optical disc that differs from a signal recorded at a density higher than the standard density, wherein a data processing unit to which a reproduction signal output from an optical pickup is supplied has a standard density. A processing unit for an error correction code inserted into a reproduction signal from the optical disc;
A processing unit for error correction codes inserted into a reproduction signal from a high-density optical disk, and a disk determination unit to which an error signal obtained from these processing units is supplied are provided. Is determined, and the error correction code processing unit on the side with less error signal is selected.

According to a fifteenth aspect of the present invention, there is provided a method for discriminating an optical disk which is a writable optical disk, wherein the frequency of a wobble signal recorded on the optical disk is detected so that an optical disk recorded at a standard density is detected. It is characterized in that an optical disc recorded at a density higher than the standard density is discriminated.

In the optical disk apparatus according to the present invention, a wobble signal output from the optical pickup is supplied with a bandpass filter having a different pass band, and a disk discriminator to which the filter output is supplied. A data processing unit to which a reproduction signal output from the optical pickup is supplied, wherein the data processing unit processes a reproduction signal from a standard density optical disc, and a data processing unit to process a reproduction signal from a high density optical disc. A data processing unit for processing the reproduction signal, wherein the disc discrimination unit determines the presence or absence of the filter output, and processes the reproduction signal using the data processing unit on the side from which the filter output is obtained. It is characterized by doing so.

[0014] In the method for discriminating an optical disc according to the present invention, a wobble signal recorded on the optical disc is detected, and an error of a cyclic code inserted in the wobble signal is detected. The optical disk is determined based on the determination output.

In the optical disk apparatus according to the present invention, a decoding section for decoding time-axis information inserted into a wobble signal reproduced from a standard-density optical disk, and a wobble reproduced from a high-density optical disk A decoding unit for decoding the time axis information inserted into the signal constitutes a decoder for the time axis information, and an address decoding unit provided in the decoding unit is provided with a cyclic code processing unit. A disc discriminating unit to which the error judgment output of each unit is supplied, wherein the disc discriminating unit selects the decoding unit having the smaller error judgment output as the decoding unit for reproducing the time information. It is characterized by.

According to the present invention, when the optical disk is a read-only optical disk, the frequency of the clock of the reproduction signal is detected, in part. This is because the clock frequency differs between the standard density optical disc and the high density optical disc. For example, when the recording density of a high-density optical disk is twice the recording density of the standard density, the clock frequency of the high-density optical disk is 1.4 times the clock frequency of the standard-density optical disk.

The second is that when the unit delay during interleaving processing of a signal to be recorded is different between when recording on a standard density optical disc and when recording on a high density optical disc, each unit delay The optical disc is determined based on the magnitude of the error signal (the number of error blocks) resulting from the deinterleaving processing with the delay amount.

For example, when the unit delay D on a standard density optical disc is D = 4 (frames) and the unit delay D on a high density optical disc is D = 7, the unit delay during deinterleave processing is An error signal when a reproduction signal with a unit delay D = 7 is input to the decoding unit where D = 4, for example, a C2 error signal (the number of error blocks of a burst error) is a reproduction signal with a unit delay D = 4. Is larger than the burst error when inputting.

Therefore, the burst error when the reproduction signal is added to each of the decoding unit in which the unit delay amount D in the deinterleaving process is D = 4 and the decoding unit in which the unit delay D is selected to D = 7 is the smallest. One can determine that the reproduced signal has been deinterleaved with the correct unit delay amount D.

More specifically, a deinterleave processing unit in which an error signal becomes zero is used as a deinterleave processing unit during reproduction. If the error signal when any of the deinterleave processing units is used does not become zero, C
The C1 error signal (the number of error blocks of the random error signal) from one decoder is equal to the first reference value r for disc determination.
efD (the number of errors is, for example, 10 to 20), and when the value is equal to or smaller than the first reference value refD, the deinterleave processing unit selected as D = 7 is used as the deinterleave processing unit at the time of reproduction. . This is because the error correction capability is higher in the interleave processing of D = 7, and it is considered that if the interleave processing is equal to or less than the first reference value, it can be determined that the disk is a high-density disk.

The random error is the disc determination reference value re.
When the difference is equal to or more than fD and the random error is equal to or less than the second reference value refR (for example, 100), a deinterleave processing unit having a small number of error blocks among the random errors is selected.

For example, when the number of error blocks is smaller when D = 4, it is determined that the disc is a standard density disc and the first disc is determined.
Is selected. Also, D = 7
If the number of error blocks is smaller in the case of, the disk is determined to be a high-density disk, and the second deinterleave processing unit is selected.

The random error is equal to the second reference value re.
fR, and the burst error becomes the third reference value refB
If the number of error blocks exceeds 2,000 (for example, the number of error blocks is 2000), it is considered that the error is no longer an error due to a difference in recording density of the disk. That is, it is considered that an error has occurred for another reason. In that case, it is convenient to inform the operator of the fact.

When the optical disk is a writable optical disk, first, the optical disk can be identified from the difference in wobble frequency. When the high-density optical disk has a recording density twice as high as the standard density, the frequency of the wobble signal has a difference of 1.4 times. Therefore, the optical disk is identified by using this frequency difference.

Second, when the polynomial for performing the error determination of the cyclic code differs between the standard density and the high density, a wobble signal is used as a reproduction signal, and the optical disc is determined based on the magnitude of the error determination output.

For example, an error judgment output using a polynomial used in a standard density optical disc performs error judgment using a cyclic code generated by the same polynomial. The judgment output becomes zero, but does not become zero in the case of a reproduction signal from a high-density optical disk. The optical disc is determined using the error determination output difference. By using the wobble signal recorded on the optical disk in this way, the optical disk can be easily and easily identified.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described in detail with reference to FIG. According to the compact disc standard, data recorded on an optical disc is
(Cross Interleave Reed-Solomon Code) encoding (error correction code processing), and the signal subjected to this CIRC encoding processing is converted to EFM (Eight to Fourteen Mod).
modulation) and recording on an optical disk.

In the CIRC encoding process, 8 bits are set to 1
It is processed as a symbol, and the CIR
The 8-bit data or parity signal per symbol obtained by the C encoding process is converted into a 14-bit signal per symbol. This EFM modulated 32
As shown in FIG. 1, a 24-bit frame synchronization signal and a 1-symbol (14-bit) subcode signal are added to symbol (32 × 14-bit) data and parity signals, By adding a 3-bit signal for combining the symbol and the frame synchronization signal,
A signal of one frame (588 channel bits) is configured.

Here, the pattern of the frame synchronization signal is a pattern in which two maximum channel pits are continuous, that is,
Assuming that “1” indicates inversion, “100000000000000000000000001” as shown in FIG.
A 24-bit switching pattern indicated by "0" is selected,
The signal level before the frame synchronization signal is low level “L”
2B, when 11T is at a high level "H" as shown in FIG. 2B and the next 11T is at a low level "L", and when the signal level before the frame synchronization signal is at a high level "H", FIG. The signal waveform shown in FIG. "T" is the minimum channel bit interval.

In a write-once optical disc such as a write-once type or a rewritable type among compact disk standards, a guide groove for a laser light guide is provided on the laser light irradiation surface side as shown in FIG. 3A. A pre-groove PG is formed. Land LA between two pregrooves PG
It is. As shown in FIG. 3B, both sides of the pregroove PG are wobbled in a slightly sinusoidal manner.
The wobble signal SWB from which the wobble component is extracted
Is FM-modulated, and encodes time axis information indicating an absolute position on the disk, a recommended value of an optimum recording power of the laser beam, and the like.

The wobble signal SWB is formed so that the center frequency becomes, for example, 22.05 kHz when the disk is rotated at a standard speed (linear speed of 1.2 m / s to 1.4 m / s). Here, ATI as time axis information
One sector of the P (Absolute Time In Pregroove) signal coincides with one data sector (2352 bytes) after signal recording, and data is written while synchronizing the data sector with the ATIP sector.

FIG. 4 shows a frame structure of ATIP information. The first 4 bits are the synchronization signal SY of the ATIP information.
"Minute" indicating the absolute time on the disc,
"Seconds" and "frames" are each indicated by "2 Digit BCD" (8 bits). Further, a 14-bit cyclic code CRC (Cy
clic Redundancy Code) is added to form one frame with 42 bits. The information such as the recommended value of the optimum recording power of the laser beam is multiplexed so as to be included in the time axis information at a certain ratio.

FIG. 5 shows a synchronization signal SYNC of ATIP information.
5A and FIG. 5B or FIG. 5B. The ATIP information shown in FIG.
The channel bit pattern shown in FIG. Where ATI
When the previous channel bit is “0”, the synchronization signal SYNC of the P information is “11101” as shown in FIG. 5B.
000 ", and the bi-phase signal DBP after the bi-phase mark modulation has a waveform shown in FIG. 5C. When the previous channel bit is "1", as shown in FIG. 5D, "00010111"
, And the bi-phase signal DBP has a waveform shown in FIG. 5E.

When the bi-phase signal DBP is obtained in this way, as shown in FIG.
The wobble signal SWB is generated by M modulation. For example, the bi-phase signal DBP shown in FIG.
Is 23.05k as shown in FIG. 4B.
Hz, 21.0 when the low level is "L"
The frequency is modulated to 5 kHz and the center frequency is 2 kHz.
A 2.05 kHz wobble signal SWB is generated.

A wobble is formed on the optical disk 10 so that a wobble signal SWB as shown in FIG. 6B is obtained when the disk is rotated at a standard speed.

FIG. 7 shows the configuration of an optical disk device 20 using the above-described optical disk 10. The optical disk 10 is rotated at a predetermined speed by a spindle motor unit 22. The spindle motor unit 22 receives a spindle drive signal SSD from a spindle motor drive unit 23 described later.
Accordingly, the optical disc 10 is driven so that the rotation speed of the optical disc 10 becomes a predetermined speed.

The optical disk 10 includes an optical disk device 20
The optical pickup 30 emits a laser beam whose light amount is controlled. The laser light reflected by the optical disk 10 is applied to a light detection unit (not shown) of the optical pickup 30. The photodetector is configured using a split photodetector or the like, generates a voltage signal corresponding to the reflected light by photoelectric conversion and current-voltage conversion, and supplies the generated voltage signal to the RF amplifier 32.

In the RF amplifier section 32, the optical pickup 3
Based on the voltage signal from 0, a read signal SRF, a focus error signal SFE, a tracking error signal STE, and a wobble signal SWB are generated. The read signal SRF, the tracking error signal STE, and the focus error signal SFE generated by the RF amplifier 32 are supplied to a clock generator / servo controller 33. The wobble signal SWB is supplied to the ATIP decoder 34.

In the clock generation / servo control unit 33, based on the supplied focus error signal SFE, the objective lens (not shown) of the optical pickup 30 is set so that the focal position of the laser beam is at the position of the recording layer of the optical disk 10. Generates the focus control signal SFC for controlling the
5 Further, based on the supplied tracking error signal STE, a tracking control signal STC for controlling the objective lens of the optical pickup 30 is generated such that the irradiation position of the laser beam is at the center position of the desired track, and the driver 35 generates the tracking control signal STC. Supply.

In the driver 35, the focus control signal S
A focus drive signal SFD is generated based on the FC, and a tracking drive signal STD is generated based on the tracking control signal STC. By supplying the generated focus drive signal SFD and tracking drive signal STD to an actuator (not shown) of the optical pickup 30, the position of the objective lens is controlled, and the laser light is focused at a desired track center position. It is controlled to tie.

The clock generation / servo control unit 33 corrects the asymmetry of the supplied read signal SRF and performs
The data is converted into a digital signal and converted into a digital signal.
To supply. The clock generation / servo control unit 33 also generates a clock signal CKRF of the read data signal DRF, and converts the generated clock signal CKRF into a data processing unit 40.
To supply.

Incidentally, some optical disks are read-only optical disks, and some are writable optical disks. These differences can be determined by detecting the presence or absence of a pre-groove formed on the optical disc. This is because the pre-groove exists only in the writable optical disk. Since the discrimination of the optical disk is already known, its description is omitted. Therefore, it is necessary to determine the difference between the standard density and the high density in a read-only optical disk, and to determine the difference between the standard density and the high density in a writable optical disk.

For this reason, the clock generation / servo control unit 33 shown in FIG. 7 further supplies the generated clock signal CKRF to the control unit 50, and compares the clock frequency at the standard disk rotation speed. It is determined whether the optical disk is a high-density optical disk or a high-density optical disk.

FIG. 8 shows the configuration of a part of the clock generation / servo control unit 33 and the frame synchronization detection unit 39.
The read signal SRF supplied from the RF amplifier unit 32 is supplied to the waveform equalization circuit 332 after the low-pass component is removed by the high-pass filter 331. The waveform equalization circuit 332 removes intersymbol interference from the signal from the high-pass filter 331. The signal SRFC from which the intersymbol interference has been removed is supplied to the limiter circuit 333 and the dropout detection circuit 334.

The limiter circuit 333 performs binarization by slicing the signal SRFC supplied from the waveform equalization circuit 332 using a slice level signal SL from an amplifier 336 described later, and obtains the obtained binarized signal. As the read data signal DRF as described above, the edge detection circuit 33
7, the frame synchronization detection unit 39, and the data processing unit 40. Further, by supplying the read data signal DRF to the integrator 335, the offset amount due to asymmetry is detected. The detected offset amount is supplied to the amplifier 336.
Is supplied to the limiter circuit 333 as the slice level signal SL, so that the read data signal DRF is generated so that the offset amount of the asymmetry is eliminated.

Further, by stopping the operation of the integrator 335 in response to the signal ST when the dropout is detected by the dropout detection circuit 334, the signal level of the slice level signal SL may fluctuate during the dropout. Is prevented.

The edge detection circuit 337 detects a change point of the signal level of the read data signal DRF, and the detection signal K
T is supplied to the clock circuit 338. Clock circuit 33
8, a clock signal CKRF of the read data signal DRF is generated using the detection signal KT, and the frame synchronization detection unit 39
The data is supplied to the data processing unit 40 and the control unit 50.

The frame synchronization detector 39 drives the shift register 391 using the supplied clock signal CKRF, and supplies the read data signal DRF to the shift register 391 and sequentially transfers the read data signal DRF. This shift register 3
The read data signal DRF sequentially transferred in step 91 is supplied to the pattern detection circuit 392 as a parallel signal, and the pattern detection circuit 392 determines whether the supplied parallel signal is equal to the signal pattern of the frame synchronization signal. Thus, the frame synchronization signal can be detected. The synchronization pattern detection signal DTS indicating the detection of the frame synchronization signal by the synchronization detection circuit 393 is supplied to the control unit 50.

The clock generation / servo control unit 33 generates a thread control signal SSC for moving the optical pickup 30 in the radial direction of the optical disk 10 so that the irradiation position of the laser beam does not exceed the tracking control range. To the thread unit 36. The thread section 36 drives a thread motor (not shown) based on the thread control signal SSC to move the optical pickup 30 to the optical disk 10.
To move in the radial direction.

The clock signal CKRF generated by the clock generation / servo control unit 33 is further supplied to the control unit 50. When a high-density optical disk is selected to have twice the recording density of the standard-density optical disk, a clock frequency 1.4 times that of the standard-density optical disk is the clock frequency of the high-density optical disk.

The control unit 50 detects this frequency difference by counting, for example, the number of clocks per unit time, and supplies the detected output CTB to the data processing unit 40, so that the data processing system for the standard density optical disk can be used. The data processing system for high-density optical disks is switched.

FIG. 9 shows an embodiment of the data processing unit 40. In this example, the data processing unit 40 includes a decoder 40A for the reproduction signal DRF and an encoder 40B for the recording data.

In this embodiment, the reproduction decoder 40A is used for decoding a reproduction signal DRF from a standard-density optical disk, and is used for decoding a reproduction signal DRF from a high-density optical disk. And a control section 50A.
Selects one of the decoders 401A or 402A according to the detection signal.

An encoder 40B for recording data includes an encoder 401B used for recording a data signal WD on a standard density optical disc and an encoder 402 used for recording a data signal WD on a high density optical disc.
B, and one of them is selected by a selection signal from the control unit 50. Data signal WD on optical disc
When writing is performed, it is previously known whether the optical disk is compatible with the standard density or the high density. Therefore, the selection signal designated by the operator is supplied from the control unit 50 to the corresponding encoder 401B or 402B.

ATIP to which wobble signal SWB is supplied
The decoder 34 has the configuration shown in FIG. This ATI
The P decoder 34 also includes a decoding unit 34A for standard density and a decoding unit 34B for high density.

The wobble signal SWB is supplied to a bandpass filter 341 constituting the standard density decoding section 34A.
The wobble signal SWB band-limited by the bandpass filter 341 to extract a wobble component is supplied to the waveform shaping unit 342.

In the waveform shaping section 342, the wobble signal S
A clock signal CKWB synchronized with the carrier component of the WB is generated, and the wobble signal SWB is binarized. The generated clock signal CKWB and the binarized wobble signal DWB are supplied to the detector 343.

The detection section 343 performs a demodulation process of the wobble signal DWB using the clock signal CKWB to generate a biphase signal DBP and a clock signal CKBP synchronized with the biphase signal DBP. The generated bi-phase signal DBP and clock signal CKBP are supplied to the address decoding unit 344.

The address decoding section 344 performs demodulation processing of the bi-phase signal DBP using the clock signal CKBP to generate an ATIP information signal DAD. Further, it detects the synchronization signal of the obtained ATIP information signal DAD and generates an ATIP synchronization detection signal FSY.

The high-density decoding section 34B has the same configuration as the standard-density decoding section 34A, and undergoes the same processing to obtain the ATIP information signal DAD and the ATIP synchronization detection signal FSY.
Are generated. Therefore, the high-density decoding unit 34B
Are assigned the corresponding reference numerals.

A pair of signals DAD, FS obtained from each of them
Any one of Y is selected by the switching means 345. A switching control signal corresponding to a standard density or high density optical disk is supplied from the control unit 50 to the terminal 346. The selected ATIP information signal DAD and ATIP synchronization detection signal FSY are supplied to the control unit 50, and the ATIP synchronization detection signal FSY is supplied to the spindle motor driving unit 23.

As described above, when the optical disk is a read-only optical disk, a standard density optical disk and a high density optical disk can be distinguished by using a clock signal of a reproduction signal when the optical disk is rotated at a standard speed.
Therefore, the disc is determined through the following procedure. (1) The position of the optical pickup 30 is roughly set by the feed mechanism of the thread unit 36, and then the FG servo is applied to drive the spindle motor unit 22 to a constant rotation speed. (2) A focus search is performed to control the optical disc 10 to perform just-focus. (3) Tracking servo after focus search may or may not be applied. (4) A reproduction signal is obtained by applying a laser beam to the optical disc 10. Then, a clock signal CKWB is obtained. (5) The number of clocks of the clock signal CKWB is measured by a counter in the control unit 50 to determine whether the optical disk is a standard density optical disk or a high density optical disk. (6) Output the determination result to a necessary place.

The following method can be used for discriminating a read-only optical disc. This discrimination method uses a burst error (a so-called C2 error) of a CIRC code which is an error correction code.

As the recording density increases, the amount of data that can be accommodated in the same area increases. Therefore, it is necessary to increase the error correction capability according to the recording density. For example, in a current optical disk (such as a CD), the unit delay amount D at the time of the interleave processing is set to D = 4 (frames). In the case of a high-density optical disk, by setting the unit delay amount D to a value of D = 4 or more, for example, D = 7, it is possible to compensate for a decrease in error correction capability. It is already known that D = 7 (for example, see Japanese Patent Application Laid-Open No. 9-91882).
Issue publication).

As described above, since the unit delay amount D at the time of the interleave processing is different, one configuration that can be considered as a processing section (decode section) of the error correction code including the deinterleave processing is a standard configuration as shown in FIG. The purpose is to separately prepare processing units for high density and high density. At this time, in the decoding unit corresponding to the unit delay amount D = 4, the unit delay amount D = 7
An error signal, for example, a burst error when the reproduction signal is input becomes larger than a burst error when a reproduction signal with the unit delay amount D = 4 is input.

Therefore, when the reproduction signal is simultaneously applied to each of the decoding unit set to the unit delay amount D = 4 and the decoding unit set to the unit delay amount D = 7, the burst error is the smallest. It can be determined that a reproduced signal that has been interleaved with a correct unit delay amount has been input. From this, it is possible to determine the optical disk by using the burst error, and it is possible to select the decoding unit by using the determination output.

Next, a specific example will be described. When a burst error is used, there is no particular need to supply a clock signal as shown in FIG. 7 to the control unit 50. In this case, the configuration of the optical disk device as shown in FIG. 11 is obtained. The data processing unit 40 used at that time can be configured as shown in FIG.

Referring to FIG. 12, the data processing unit 40A supplies a read data signal DRF to an EFM demodulator 71 to perform EFM demodulation, and then performs error correction processing (CIRC processing) including deinterleave processing for standard density. It is supplied to the decoding unit 72.

The unit delay amount D in the decoding unit 72 is
When D = 4, correct deinterleaving processing is performed when D = 4.
Error correction processing and deinterleave processing by C are performed. The reproduced signal after the error correction processing is supplied to the switching means 74.

Similarly, the EFM demodulated output is further supplied to the high-density decoding unit 73. The unit delay amount D used for the deinterleave processing in the decoding unit 73 is, for example, D = 7 as described above. D = 7 is an example,
Other numbers can be used. Decoding sections 72 and 7
In this example, a burst error (C2 error signal) is supplied to an error size determination unit 75 constituting a disk determination unit, and the size of the burst error (the number of error blocks) is determined.

The judgment result is supplied to the switching means 74. Since the decoding processing with the smaller burst error is considered to be the error correction processing with the correct unit delay amount, the decoding unit with the smaller burst error is selected.

For example, when a signal is reproduced from the optical disk 10 on which the interleave processing is performed and the unit delay amount is D = 4, when the reproduced signal DRF is input to the respective decoding units 72 and 73, the decoding unit 72 The number of error blocks of the burst error obtained from the side is
Since the number of error blocks of the burst error obtained from the decoding unit 73 is smaller than that, the optical disk being reproduced is determined to be a standard density optical disk in this case, and the switching unit 74 selects the output of the decoding unit 72.

Conversely, when a signal is reproduced from the optical disk 10 on which the interleave processing is performed and the unit delay amount is D = 7, when the reproduced signal DRF is input to the respective decoding units 72 and 73, Is that the number of error blocks of the burst error obtained from the decoding unit 73 side is smaller than the number of error blocks of the burst error obtained from the decoding unit 72 side. Upon determining that the optical disk is an optical disk, the switching unit 74 selects the output of the decoding unit 73.

The selected reproduction signal is further subjected to a descrambling process, an ECC (Error Correcting Code) error correction process, and the like in an error correction processing section 76 having a descrambling function. The data signal subjected to the error correction processing is stored in a RAM 42 as a buffer memory, and then supplied as a reproduced data signal RD to an external computer device or the like via an interface 43.

The signal after the EFM demodulation is supplied to the synchronizing signal detecting section 88, and the demodulated signal is converted into the frame synchronizing signal F
SZ is detected and supplied to the spindle motor drive unit 23. In the spindle motor drive unit 23, when recording a signal on the optical disc 10, the A
The TIP synchronization detection signal FSY is used. When reproducing the signal recorded on the optical disk 10, the optical disk 10 is desirably used by using the frame synchronization signal FSZ from the data processing unit 40 or the ATIP synchronization detection signal FSY from the ATIP decoder 34. A spindle drive signal SSD for rotating at a speed of? By supplying the spindle drive signal SSD generated by the spindle motor drive unit 23 to the spindle motor unit 22, the optical disc 10 is rotated at a desired speed.

Further, when the recording data signal WD is supplied from an external computer device via the interface 43, the data processing unit 40B for performing the encoding process temporarily stores the recording data signal WD in the RAM 42, and simultaneously formats the recording data signal WD. In the encoder 81, RA
The recording data signal WD stored in M42 is read and encoded into a predetermined sector format, and an error correction code adding section 82 having a scrambling function at the subsequent stage is provided.
Then, ECC for error correction is added to the scrambled recording data signal.

Thereafter, the CIRC encoding units 83 and 84
Supplied to One encoding unit 83 is an encoder used when recording data on an optical disc for standard density, performs CIRC processing and interleave processing, and a unit delay amount D during interleave processing is D = 4.
Is made.

The other encoder 84 is an encoder used when recording data on a high-density optical disk. The encoder 84 performs a CIRC process and an interleave process. 7 is made. One of the outputs of the encoding units 83 and 84 is selected by the switching unit 85. Switching to c or d side is performed by a switching signal output from the control unit 50. In the control unit 50, it is specified in advance which type of optical disc the recording density should be used to record data. In this case, the encoding unit 83 or 84 suitable for the optical disc to be used is selected. The selected encode output is further subjected to EFM modulation processing by an EFM modulator 86 to generate a final write signal DW. This write signal DW is supplied to the write compensator 37 (see FIG. 11).

The write compensator 37 generates a laser drive signal DLA based on the supplied write signal DW and supplies it to the laser diode of the optical pickup 30. here,
The write compensator 37 changes the signal level of the laser drive signal DLA according to the characteristics of the recording layer of the optical disc 10, the spot shape of the laser beam, the recording linear velocity, etc., based on the power compensation signal PC from the controller 50 described later. After the correction, the power of the laser beam output from the laser diode of the optical pickup 30 is optimized, and the signal recording operation is performed.

A ROM 51 is connected to the control unit 50, and controls the operation of the optical disk device 20 based on an operation control program stored in the ROM 51. For example, the signal DSQ such as a subcode generated by the data processing unit 40 or the ATIP information signal D from the ATIP decoder 34
The reproduction position and the recording position on the optical disk 10 are determined based on the AD, and the control signal CTA and the like are supplied to the clock generation / servo control unit 33 and the data processing unit 40 to perform the data recording and reproduction operation. Do. Further, a power compensation signal PC is generated based on the setting information of the recording laser power indicated by the ATIP information signal DAD, and
To supply.

A control signal CTC is supplied from the control unit 50 to the RF amplifier unit 32 so that the RF amplifier unit 32 controls on / off of the laser diode of the optical pickup 30 and reduces disturbance to laser noise and a read signal. A process of superimposing a high frequency on the laser beam is also performed. Further, the control unit 50 controls the transmission of the AT
On the basis of the IP synchronization detection signal FSY and the synchronization pattern detection signal DTS from the frame synchronization detection unit 39, it is determined whether or not the optical disk is a high-density optical disk whose recording capacity has been increased.

In the configuration shown in FIG. 12, the following procedure is performed when discriminating an optical disk. (1) The position of the optical pickup 30 is roughly set by the feed mechanism of the thread unit 36, and then the FG servo is applied to drive the spindle motor unit 22 to a constant rotation speed. (2) A focus search is performed to control the optical disc 10 to perform just-focus. (3) Perform tracking servo after focus search. (4) A reproduction signal is obtained by applying a laser beam to the optical disc 10. (5) Deinterleave processing at D = 4 and CIR
The C code is decoded and the number of burst error blocks is counted. (6) Deinterleave processing at D = 7 and CIR
The C code is decoded and the number of burst error blocks is counted. (7) If the number of burst error blocks is smaller when D = 4, the optical disc is determined to be a standard density optical disc. If the number of burst error blocks is smaller when D = 7, the optical disc is determined to be a high density optical disc.

Subsequently, the data processing unit 40 shown in FIG.
Next, another embodiment will be described. In the embodiment of FIG. 12, the unit delay amount D is set to D = 4, and the deinterleave processing and CIRC processing unit 7 set to D = 7.
2 and 73 are simultaneously driven and discrimination of the disc is performed based on the burst error obtained from each.
Or 73 is selected. The embodiment described below performs the determination process sequentially instead of performing the determination process simultaneously.

In this sequential determination process, first, D
When the burst error is detected when the burst error is equal to 4, and the burst error does not exist, that is, when the number of error blocks is zero, the deinterleave processing and the CIRC processing unit 72 are selected without performing the determination processing of D = 7.

When the burst error at D = 4 is not zero, deinterleave processing set at D = 7 and C
Reference is made to a burst error obtained from the IRC processing unit 73. When the burst error at that time is zero,
It is determined that the disc is a high-density disc, and the deinterleave processing and CIRC processing unit 73 is selected.

As described above, when the data processing units are sequentially selected, it is not necessary to simultaneously operate the deinterleave processing and the CIRC processing units 72 and 73. In this case, by selectively supplying the clock signals CKRF to be supplied to the respective components as shown in FIG. 13, the operation can be selectively performed.

Therefore, in this case, as shown in FIG. 13, a changeover switch 77 to which the clock signal CKRF is supplied is provided, and the processing units 72 and 73 supply the clock signal CKRF.
RF is selectively supplied. The processing unit to which the clock signal CKRF is not supplied is a so-called sleep mode (standby mode)
It has become.

Therefore, the judgment output generated by the error judgment section 75 is supplied to the control section 50 shown in FIG. 11, and the switching signal SWC generated by the control section 50 is supplied to the changeover switch 77 via the terminal 78. By performing the supply control of the clock signal as described above, the operation state is sequentially set. Therefore, for example, when the processing unit 72 is selected, the clock signal CKRF holds the illustrated switching state. When this sequential processing is performed, unnecessary circuit systems are in a sleep mode, which is an effective means for saving power.

Next, as in the case of FIG. 12, as the data processing unit 40, the standard decoder and the high-density decoder are respectively independent. However, since a fundamentally different part is a deinterleave processing unit, it is sufficient to provide only the deinterleave processing unit with a standard processing unit and a high-density processing unit. FIG. 14 shows an embodiment of the data processing unit 40 following such a concept.
The same parts as those in FIG. 12 are denoted by the same reference numerals, and description thereof will be omitted.

To explain from the recording system, the interface 4
The data signal WD to be recorded, which is input via the S3, is encoded into a predetermined sector format by a format encoder 81, and then subjected to scrambling and ECC processing by a scrambling process and an ECC addition process for error correction. . Thereafter, the parity of the Reed-Solomon code is added by the C2 encoder 872.

The C2 encoded output is subjected to an interleave processing by an interleave processing section 873 in which D = 4 or D = 7 is set as a unit delay amount. Therefore, the interleave processing unit 873 includes a first interleave processing unit 873A where D = 4 and a second interleave processing unit 873B where D = 7. Then, a switching signal from the control unit 50 is supplied to the interleave processing unit 873 via the terminal 874, and interleave processing is performed according to the difference in recording density of the loaded optical disk.

The interleaved C2 encoded output is further supplied to a C1 encoder 875 to read the
The Solomon code is C1 encoded and a predetermined parity is added. The odd-numbered delay section 876 delays only the odd-numbered symbols by one frame in the C1 encoded output and the interleaved output to which the parity has been added. Then, only the parity symbols are inverted in sign by the next sign inverting section 878. After performing this processing, the EFM processing unit 86 performs 8-1.
4 conversion processing is performed and recorded on the optical disk 10.

The data signal reproducing system is as follows. The reproduction signal DRF reproduced from the optical disc 10 is converted to 14-8 data by the EFM processing unit 71 and returned to the original 8 sample data. The time series of the samples is aligned.
After that, the parity inverting section 773 inverts the parity code added to the CIRC code and returns the data at the time of recording. Then, the CIRC code is decoded by the C1 decoder 774.

[0094] The decoded CIRC code and other reproduced symbols are supplied to a deinterleave processing section 775. The deinterleave processing unit 775 includes a first deinterleave processing unit 775A set to D = 4 and D = 7
And a second deinterleave processing unit 775B set to, and one of the deinterleave processing units 775A and 775B is selected by a switching signal supplied from the control unit 50 via the terminal 779.

The decoded output subjected to the deinterleaving processing is supplied to a C2 decoder 776, where the decoding processing of C2 is performed, and then the descrambling processing is performed by the descrambling section 76 to reproduce the original recording data RD.

In this embodiment, as described above, two deinterleave processing units 775A and 775 having different unit delay amounts are used as deinterleave processing units 775, respectively.
B is provided, and it is automatically determined whether the set optical disc 10 has been recorded at a standard recording density or has been recorded at a high density. Therefore, the reproduction error signal from the C2 decoder 776 is supplied to the terminal 777 as shown in FIG.
Is supplied to the control unit 50 in this example, and the determination process is executed.

The reproduction error signal from the C2 decoder 776 is a C2 error signal, that is, a burst error, and is output as the number of error blocks. In this embodiment, the reproduction error signal from the C1 decoder 774 is used for disc discrimination and another error discrimination as needed. Therefore, this reproduction error signal is supplied to the terminal 778.
Is supplied to the control unit 50 via the.

In the control unit 50, disc discrimination processing is performed. The embodiment will be described below. This embodiment is an example of a sequential discrimination process, in which a discrimination process using a first deinterleave processing unit 775A is first performed,
Next, determination processing using the second deinterleave processing unit 775B is performed.

First, the first deinterleave processing section 775
Select A. For the selection, a method of selectively supplying the clock signal CKRF as described above can be employed.

In the first deinterleave processing unit 775A, the unit delay amount is selected to be D = 4 corresponding to the standard density. The burst error BE4 from the C2 decoder 776 at that time is detected, and when the burst error BE4 does not exist, that is, when the number of error blocks is zero, the deinterleave processing unit 775A does not need to perform the determination process for D = 7. Select

When the burst error BE4 at D = 4 is not zero, the second deinterleave processing unit 775B set at D = 7 is operated to refer to the burst error BE7 at that time. When the burst error BE7 is zero, it is determined that the disc is a high-density disc, and the deinterleave processing unit 775B is used as it is as a deinterleave processing unit during reproduction.

Next, the processing when both the burst errors BE4 and BE7 are not zero will be described. In this case, C
The determination is also made with reference to the C1 error signal (random error RE) obtained from one decoder 774. As the random error RE, for example, the number of error blocks when reproduced for one second (75 subcode frames = 1 sector) can be used. The number of error blocks of the random error RE is compared with a first reference value refD for disc determination. The first reference value refD can be selected from 10 to 20 error blocks.

The random error RE is equal to the first reference value ref.
D, the optical disk is regarded as a high-density optical disk and the second deinterleave processing unit 77
5B is selected. This is because if dust or the like adheres to the surface of the optical disk to be reproduced, the probability of occurrence of such random errors is high.

The random error RE is equal to the first reference value red.
D and much less than the second reference value refR (for example, 100 error blocks), the smaller of the burst errors in the reference reproduction period (1 second in the above example) Select the deinterleave processing unit. For example, when it is determined that the burst error BE4 has a smaller number of error blocks, the first deinterleave processing unit 775A is selected by regarding the mounted optical disk 10 as a standard optical disk.

On the other hand, the random error RE is
And the burst error BE exceeds the third reference value refB (for example, the number of error blocks of 1000), it is considered that the error is not caused by a difference in recording density but is caused by another cause. . This is because errors of such a large value do not usually occur only when the recording densities are different.

In this case, the operator is informed that an error has occurred due to another cause. The notification can be made by, for example, blinking an alarm display element or displaying an error message on a panel.

Next, a method for determining the standard density and the high density for a writable optical disk and an optical disk apparatus using the method will be described.

At least two methods are conceivable for discriminating between the standard density and the high density for a writable optical disk. (A) A method using the frequency of a wobble signal. (B) A method using the error determination result when the polynomial for error determination of the cyclic code differs between the standard density optical disc and the high density optical disc.

(A) In the case of a standard density optical disk, the center frequency (fWB) of the wobble signal is 22.05 MHz as described above. The center frequency (fWB ') of an optical disk whose recording density is twice the standard density is 1.4 times 30.87 MHz. By utilizing this frequency difference, the optical disk can be reliably determined.

In this case, the optical disk device can directly follow the basic configuration shown in FIG. The data processing unit 40 of the reproduction signal DRF has the same configuration as that shown in FIG. 9 and, in addition to the encoder 40B composed of a pair of encoders 401B and 402B, reproduces a reproduction signal from an optical disc recorded at a standard density. A data processing unit (decoder) 401A for decoding and a data processing unit 40 for decoding a reproduction signal from an optical disc recorded at high density
2A.

For detecting the frequency of the wobble signal, a dedicated detection system can be provided, but a part of the configuration of the ATIP decoder 34 can be used. FIG.
The fifth embodiment is an example of the latter.

The basic configuration of FIG. 15 is based on the AT described in FIG.
The configuration is almost the same as that of the IP decoder 34. The difference is that a disc discriminating section 347 is provided, and the switching means 345 is switched by the discrimination output.

The output of the band filter 341 for the standard density optical disk and the output of the band filter 351 for the high density optical disk are supplied to the disk determination section 347. The bandpass filter 341 is a frequency band of a wobble signal obtained when a standard density optical disc is reproduced (see FIG. 16).
And the other bandpass filter 351 is a filter for passing the frequency band (see FIG. 16) of a wobble signal obtained when a high-density optical disk is reproduced.

Therefore, when the optical disk 10 is rotationally driven at such a speed that the frequency of the wobble signal becomes the center frequency, and when the optical disk being reproduced has the standard recording density, the wobble signal is output only from the bandpass filter 341. Is obtained, and nothing is output from the other bandpass filter 351. The opposite is true for a high-density optical disk. Therefore, by determining the presence or absence of the filter output, it is possible to reliably determine whether the optical disk being reproduced is of a standard density or a high density.

When only the filter output from the bandpass filter 341 is obtained, the switching means 34 is used based on the discrimination output.
At 5, it is switched to the a side. Thus, correct ATIP decoding processing can be realized.

Also in the configuration of FIG. 15, the following procedure is performed when discriminating an optical disk. (1) The position of the optical pickup 30 is roughly set by the feed mechanism of the thread unit 36, and then the FG servo is applied to drive the spindle motor unit 22 to a constant rotation speed. (2) A focus search is performed to control the optical disc 10 to perform just-focus. (3) After the focus search, the optical disc 10 is rotationally driven with or without tracking servo. (4) A reproduction signal (wobble signal) is obtained by applying a laser beam to the optical disc 10. (5) The wobble frequencies from the bandpass filters 341 and 351 are detected. (6) When the wobble frequency detected at the standard disk rotation speed is substantially equal to the value expected for the standard density (the center frequency is 22.05 MHz),
This optical disk is determined to be a standard density optical disk.

On the other hand, the wobble frequency is a value expected as a high density (the center frequency is 30.
When the value is close to 87 MHz), the optical disk is determined to be a high-density optical disk.

In addition to such a determination method, when a standard density optical disk is loaded, a filter output can only be obtained from the bandpass filter 341. Therefore, it is also possible to determine the optical disk based on the presence or absence of each filter output. it can. For example, when only the filter output of the bandpass filter 341 is input to the disc discriminating section 347, the optical disc may be judged to be a standard density optical disc.

Of course, instead of providing the disc discriminating section 347, these two filter outputs may be supplied to the control section 50 to judge the wobble frequency or the presence or absence of the filter output by software.

Regarding (B) The polynomial for determining the error of the cyclic code (CRC) is as follows: P (x) ′ = x ¹⁶ + x ¹² + x ⁵ +1 (1) when the optical disc is normally a standard density optical disc. An error is determined using a simple polynomial. On the other hand, it is conceivable to set a polynomial for determining an error of a cyclic code (CRC) on a high-density optical disc differently from the above. For example, the following polynomial can be considered. ^{P (x) = x 14 +} x 12 + x 10 + x 7 + x 5 + x 4 + x 2 +1 ··· (2)

When the error determination of the cyclic code is performed using different polynomials as described above, the difference in the recording density of the optical disk can be determined from the result of the determination polynomial.

In this case, the optical disk device can follow the basic configuration shown in FIG. 11 as it is. The data processing unit 40 of the reproduction signal DRF has the same configuration as that shown in FIG. 9 and, in addition to the encoder 40B composed of a pair of encoders 401B and 402B, reproduces a reproduction signal from an optical disc recorded at a standard density. A data processing unit (decoder) 401A for decoding and a data processing unit 40 for decoding a reproduction signal from an optical disc recorded at high density
2A.

FIG. 17 shows an embodiment of the ATIP decoder 34 to which the present invention is applied. The ATIP decoder 34 itself is almost the same as the ATIP decoder configuration of FIG. 9 or FIG.

In this embodiment, the disk discriminating section 349
And an error determination result P (x) for the ATIP information signal DAD decoded by the address decoding unit 344
And the ATI decoded by the address decoding unit 354
An error determination result P (x) ′ for the P information signal DAD is supplied.

The discrimination result P
The magnitude relation between (x) and P (x) ′ is compared. That is,
When the optical disk is a standard density optical disk, the relationship P (x) = 0 <P (x) '(3) holds, and when the optical disk is a high density optical disk, P (x)> P (x) '= 0... (4) The switching unit 345 is controlled so that the decoding unit 34A or 34B having the smaller error determination result is selected based on the determination result.

In the configuration shown in FIG. 17, the following procedure is performed when discriminating an optical disk. (1) The position of the optical pickup 30 is roughly set by the feed mechanism of the thread unit 36, and then the FG servo is applied to drive the spindle motor unit 22 to a constant rotation speed. (2) A focus search is performed to control the optical disc 10 to perform just-focus. (3) Perform tracking servo after focus search. (4) A reproduction signal (wobble signal) is obtained by applying a laser beam to the optical disc 10. (5) When the error correction result P (x) is smaller than the value of P (x) ′, the optical disc is determined to be a standard density optical disc. When P (x) ′ is smaller than the value of P (x), the high density optical disc is determined. Is determined.

Of course, instead of providing the disk discriminating section 349, these two filter outputs are supplied to the control section 50, and the error judgment results P (x) and P (x) 'are softly obtained.
May be determined.

It is clear that the error correction result of the cyclic code can be used not only for a write-once optical disc but also for discrimination between a standard density and a high density in a read-only optical disc.

In the above-described embodiment, the optical disk to be determined is not limited to the CLV type optical disk. Even if the disk is a CAV type optical disk or a zone CLV type optical disk, the same measurement is performed at a predetermined rotational speed and at a predetermined position. Of course, the discrimination of the optical disk can be performed.

[0130]

As described above, according to the present invention, when the loaded optical disk is of a read-only type, the optical disk can have a standard density by detecting the clock frequency of the reproduction signal or detecting the burst error signal. Or high density can be easily and reliably determined. Its configuration is also simple. In some cases, it is possible to determine that the error of the optical disk is not a difference in recording density but an error due to another cause.

When the loaded optical disk is of the write-once type or rewritable type, the frequency of the wobble signal is detected or the error correction result of the cyclic code is detected so that the optical disk has a standard density. Or high density can be easily and reliably determined. Its configuration is also simple.

[Brief description of the drawings]

FIG. 1 is a diagram showing a frame structure of a signal recorded on an optical disc.

FIG. 2 is a diagram illustrating a frame synchronization signal.

FIG. 3 is a diagram showing a configuration of an optical disc.

FIG. 4 is a diagram showing a frame structure of ATIP information.

FIG. 5 is a diagram showing ATIP information and a biphase signal.

FIG. 6 is a diagram illustrating a relationship between a biphase signal and a wobble signal.

FIG. 7 is a diagram showing a configuration of an optical disk device when a read-only optical disk is used.

8 is a diagram showing a part of the configuration of a clock generation / servo control unit and a frame synchronization detection unit in FIG. 7;

9 is a diagram illustrating a schematic configuration of a data processing unit in FIG. 7;

FIG. 10 is a diagram showing a configuration of an ATIP decoder in FIG. 7;

FIG. 11 is a diagram showing a configuration of an optical disk device when a writable optical disk is used.

FIG. 12 is a diagram showing a configuration of a data processing unit in FIG. 11 (part 1).

FIG. 13 is a diagram illustrating a configuration of a data processing unit in FIG. 11 (part 2);

FIG. 14 is a diagram illustrating a configuration of a data processing unit in FIG. 11 (part 3);

15 is a diagram illustrating a configuration of an ATIP decoder in FIG. 11 (part 1); FIG.

FIG. 16 is a frequency characteristic diagram of the bandpass filter.

FIG. 17 is a diagram showing a configuration of the ATIP decoder in FIG. 11 (part 2).

[Explanation of symbols]

10 optical disk, 20 optical disk device, 2
2 ... Spindle motor unit, 23 ... Spindle motor drive unit, 30 ... Optical pickup, 32 ... R
F amplifier section, 33 ... clock generation / servo control section,
34: ATIP decoder, 34A: decoding unit for standard density, 34B: decoding unit for high density, 345
... Switching means, 35 ... Driver, 36 ...
Thread part, 37 write compensator, 39 frame synchronization detector, 40 data processor, 40A
Decoder, 40B ... Decoder, 41, 42 ... R
AM, 43 ... interface, 50 ... control unit,
72, 73, 83, 84 ... CIRC processing unit, 331
... High-pass filter, 332 ... Waveform equalization circuit, 33
3 Limiter circuit 334 Dropout detection circuit 335 Integrator 336 Amplifier 3
37 ... edge detection circuit, 338 ... clock circuit, 341 ... band filter, 342 ... waveform shaping section, 343 ... detection section, 344 ... address decoding section, 347,349 ...・ Disk discriminator, 391
..Shift registers, 392... Pattern detection circuits,
393... Synchronization detection circuit

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shinji Ota 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation F-term (reference) 5D044 BC02 CC06 GK18 5D066 HA01 5D090 AA01 CC09 CC18 DD03 GG02 JJ11

Claims (20)

[Claims] When an optical disc is a read-only optical disc, an optical disc recorded at a standard density or an optical disc recorded at a density higher than the standard density according to the number of clocks extracted from a reproduction signal reproduced from an optical pickup. An optical disc discriminating method characterized in that the discrimination is made. 2. A clock generation / servo control unit to which a reproduction signal output from an optical pickup is supplied, and a control unit to which a clock output from the clock generation / servo control unit is supplied, are provided. The generation / servo control unit has an edge detector of the binarized reproduced signal and a clock generation unit generated based on the edge output, and the clock signal output from the clock generation unit performs the above-described control. The clock signal is supplied to the optical disc unit, and the clock signal is counted, and whether the optical disc is recorded at a standard density or an optical disc recorded at a density higher than the standard density is determined based on the number of clocks per unit time. An optical disc device characterized by the above-mentioned. 3. A data processor for decoding a reproduction signal from the optical disk recorded at the standard density, and a data processor for decoding a reproduction signal from the optical disk recorded at a higher density. 3. The optical disk device according to claim 2, further comprising a processing unit, wherein the data processing unit is selected according to the number of clocks. 4. A read-only optical disc, wherein a unit delay during interleaving processing of a signal to be recorded is a signal recorded at a standard density and a signal recorded at a density higher than the standard density. An optical disc discriminating method characterized by discriminating between the standard density recording optical disc and the high density recording optical disc based on the magnitude of the error due to the difference in the unit delay amount when different. 5. A signal recorded at a standard density, wherein a unit delay during interleaving of a signal to be recorded is:
An optical disc device for a read-only optical disc that differs from a signal recorded at a density higher than the standard density, wherein a data processing unit to which a reproduction signal output from an optical pickup is supplied has a standard density. A processing unit for an error correction code inserted into a reproduction signal from an optical disk, a processing unit for an error correction code inserted into a reproduction signal from a high-density optical disk, and a disk to which error signals obtained from these processing units are supplied A discriminating section is provided, and the disc discriminating section determines whether the error is large or small based on the difference in the unit delay amount, and selects the error correction code processing section on the side with less error. Characteristic optical disk device. 6. The optical disk device according to claim 5, wherein a burst error signal is used as said error signal. 7. A switch for selectively switching a clock supplied to the pair of error correction code processing sections is provided. The switch is controlled based on an output of the disk discriminating section, and the clock is controlled by the switch. When the disk discriminating unit determines that the number of error blocks of the error signal in the one error correction code processing unit supplied first is zero, the one error correction code processing unit supplied with the clock is used. Is selected as the processing unit at the time of reproduction, and when it is determined that the number of error blocks of the error signal from the one error correction code processing unit is larger than zero, the clock is supplied to the other error correction code processing unit. And the error signal from the error correction code processing section is determined, and the number of error blocks in the error signal at that time is zero. Optical disk apparatus according to claim 5, wherein the certain time error correction code processing unit of the other, characterized in that it is selected as a processing unit at the time of reproduction. 8. When the number of error blocks in the error signal from the other error correction code processing unit is not zero, the number of error blocks in the error signal from the one error correction code processing unit is the first for disk discrimination. 8. The optical disk device according to claim 7, wherein when the difference is equal to or less than the reference value, the other error correction code processing unit is selected as a processing unit during reproduction. 9. The data processing unit includes at least a C1 decoder, first and second deinterleave processing units having different unit delay amounts, and a C2 decoder. The data processing unit includes an error signal obtained from the C2 decoder. 6. The optical disk device according to claim 5, wherein one of the first and second deinterleave processing units is selected based on the selected one. 10. When the number of error blocks of an error signal from the C2 decoder when the first deinterleave processing unit is selected is zero, the first deinterleave processing unit performs deinterleave processing during reproduction. When the number of error blocks in the error signal is not zero, the error signal from the C2 decoder obtained when switching to the second deinterleave processing unit is determined, and the number of error blocks in the error signal is determined. 10. The optical disc apparatus according to claim 9, wherein when the value of is zero, the second deinterleave processing unit is selected as a deinterleave processing unit during reproduction. 11. When the number of error blocks in an error signal is not zero, no matter which deinterleave processing unit is selected, the number of error blocks in an error signal when the first deinterleave processing unit is used is discriminated. 10. The optical disk device according to claim 9, wherein when the value is equal to or less than the first reference value, the second deinterleave processing unit is selected as a deinterleave processing unit during reproduction. 12. When the number of error blocks of an error signal obtained from the C1 decoder is equal to or more than the first reference value for disc discrimination and equal to or less than a second reference value,
10. The optical disk device according to claim 9, wherein a deinterleave processing unit having a smaller number of error blocks among error signals from the C1 encoder and the C2 encoder is used as a deinterleave processing unit during reproduction. 13. The number of error blocks in the error signal obtained from the C1 decoder exceeds the second reference value, and the number of error blocks in the error signal obtained from the C2 decoder is equal to the third reference value for disc discrimination. 10. The optical disk apparatus according to claim 9, wherein when the number exceeds the threshold, it is determined that the error is caused by an error other than the disk. 14. The discrimination processing in the disc discrimination unit is performed by software.
An optical disk device as described in the above. 15. A writable optical disc, wherein an optical disc recorded at a standard density and an optical disc recorded at a density higher than the standard density are detected by detecting the frequency of a wobble signal recorded on the optical disc. A method for determining an optical disk, characterized in that: 16. A band filter to which a wobble signal output from the optical pickup is supplied, each having a different pass band, a disc discriminator to which the filter output is supplied, and a reproduction signal output from the optical pickup. The data processing unit has a data processing unit that processes a reproduction signal from a standard density optical disc, and a data processing unit that processes a reproduction signal from a high density optical disc. An optical disc device, wherein the disc discriminating section discriminates the presence or absence of the filter output, and uses the data processing section on the side from which the filter output is obtained to process the reproduced signal. 17. A decoding unit for processing a wobble signal from a standard-density optical disk in a time-axis information decoder for decoding time-axis information recorded on the optical disk, and for processing a wobble signal from the high-density optical disk. 17. The optical disc apparatus according to claim 16, wherein a decoding section is provided for each of the decoding sections, and each of the decoding sections is provided with a filter for extracting the wobble signal, and the filter is also used as the band filter for discriminating the optical disc. . 18. A writable optical disk, wherein a wobble signal recorded on the optical disk is detected, and the optical disk is determined based on an error determination output of a cyclic code inserted in the wobble signal. A method for discriminating an optical disk, comprising: 19. A decoding section for decoding time axis information inserted in a wobble signal reproduced from a standard density optical disc, and a decoding section for decoding time axis information inserted in a wobble signal reproduced from a high density optical disc. A decoder for time axis information is configured by the unit and the address decoding unit provided in the decoding unit,
A cyclic code processing unit is provided, and a disk discriminating unit is provided to which an error judgment output from the address decoding unit is supplied. In the disc discriminating unit, the decoding unit with the smaller error judgment output is set to the time An optical disc device characterized in that it is selected as a decoding section for reproducing information. 20. The apparatus according to claim 19, wherein the processing in said disk discriminating section is performed by software.
An optical disk device as described in the above.