JP2002203344A - Magneto-optical disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a magneto-optical disk device, in which a magneto-optical recording medium is exactly testable. SOLUTION: By a controller 114, a prescribed signal is recorded on the magneto-optical recording medium 100 and this recorded signal is reproduced to test the recording medium 100. Then, the controller 114 discriminates whether each frame of the recording medium 100 is a defective frame or not, on the basis of the number of errors of the reproduced signals inputted from a BCH recorder 112. When the magneto-optical disk device 200 is forcibly stopped by some or other reason, the controller 114 restarts the test by returning back to the top of the band whereon the test is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magneto-optical disk drive capable of recording and reproducing signals on and from a magneto-optical recording medium to accurately perform a test.

[0002]

2. Description of the Related Art In a magneto-optical disk, lands and grooves are alternately formed in the radial direction, and a signal is recorded on both the lands and the grooves to increase the density.

Recently, standardized AS-MO (Adva)
nounced Storage Magneto Opt
According to the "ical disk" standard, a fine clock mark which is a reference for generating a clock used for recording or reproducing data is formed at a predetermined cycle. Specifically, this fine clock mark is provided with a groove having a length of about 3 to 4 data channel bits at a predetermined period in a land, and a land having a length of about 3 to 4 data channel bits at a predetermined period in the groove. Is formed.

In a magneto-optical disk according to the AS-MO standard, a clock is generated by detecting a fine clock mark, and recording and reproduction of signals are performed in synchronization with the generated clock.

On the magneto-optical disk according to the AS-MO standard, signals are recorded and reproduced on a frame basis. When the magneto-optical disk is shipped, it is tested whether or not each frame has a defect. Then, the number of the frame in which the defect exists is written in a predetermined location on the magneto-optical disk.

[0006]

However, in the conventional test, when the apparatus is stopped due to the inability to accurately generate a clock while recording a signal, the next time the recording operation is restarted, The recording operation is started from the block next to the block recorded before the stop of the apparatus. Then, there is an area where the signal for the test is not recorded,
A problem arises in that it is not possible to test whether the recording and reproduction of signals can be accurately performed on the entire magneto-optical disk.

SUMMARY OF THE INVENTION An object of the present invention is to provide a magneto-optical disk drive capable of accurately testing a magneto-optical recording medium.

[0008]

A magneto-optical disk device according to the present invention includes a plurality of frames, each having a plurality of bands arranged radially concentrically. A magneto-optical disk drive for recording and / or reproducing signals on a magneto-optical recording medium, irradiating the magneto-optical recording medium with a laser beam and detecting reflected light thereof, and a magnetic field modulated by the recording signal , A signal processing circuit for performing signal processing on a magneto-optical signal detected by the optical pickup from the magneto-optical recording medium, and detecting a defective frame based on a reproduced signal output from the signal processing circuit. A control circuit for controlling the optical pickup and the magnetic head so as to record the number of the defective frame obtained on the magneto-optical recording medium. When air disk device has been suspended, it controls the optical pickup and a magnetic head so as to start the recording and / or reproduction of signals from the head of the band.

In the magneto-optical disk drive according to the present invention, a signal is recorded on the magneto-optical recording medium by magnetic field modulation recording, and the recorded signal is reproduced to determine whether or not a frame included in each band is a defective frame. Is done. Then, the control circuit controls the optical pickup and the magnetic head to return to the head of the band being tested and restart the test if the device is forcibly stopped during the test.

Therefore, according to the present invention, a test can be performed on the entire magneto-optical recording medium.

Preferably, the magneto-optical disk device further includes a clock generation circuit that generates a clock based on a fine clock mark detection signal that has detected a fine clock mark formed on the magneto-optical recording medium, and the control circuit includes a clock generation circuit. When a clock error is input from the generation circuit, the magneto-optical disk device is forcibly stopped, and the optical pickup and the magnetic head are controlled so as to start recording and / or reproducing signals from the head of the band.

If the clock is not accurately generated in the clock generation circuit during the test and the device is forcibly stopped, the control circuit returns to the head of the band under test and restarts the test.

Therefore, according to the present invention, a test can be performed on the entire magneto-optical recording medium.

Preferably, the magneto-optical disk device further includes an address detection circuit for detecting an address of data recorded on or to be recorded on the magneto-optical recording medium,
The control circuit forcibly stops the magneto-optical disk drive when an address non-detection is input from the address detection circuit, and controls the optical pickup and the magnetic head to start recording and / or reproducing signals from the head of the band. I do.

When the address detection circuit cannot detect the address from the magneto-optical recording medium and the device is forcibly stopped, the control circuit returns to the head of the band under test and restarts the test.

Therefore, according to the present invention, a test can be performed over the entire magneto-optical recording medium.

Preferably, the control circuit of the magneto-optical disk device, when detecting a predetermined number or more of defective frames, records on the magneto-optical recording medium that the use of the magneto-optical recording medium is prohibited. Control the head.

When a predetermined number or more of the plurality of frames are defective frames, the control circuit prohibits the use of the magneto-optical recording medium and writes the fact to the magneto-optical recording medium.

Therefore, according to the present invention, only high quality magneto-optical recording media can be shipped.

Preferably, each of the plurality of bands includes a test area and a data area, and when a control circuit of the magneto-optical disk device detects a predetermined number or more of defective frames continuously from the test area, the control circuit of the magneto-optical disk apparatus performs The optical pickup and the magnetic head are controlled to record on the magneto-optical recording medium that the use of the recording medium is prohibited.

When a predetermined number or more of defective frames are continuously detected in the test in the test area among the test area and the data area constituting the band, the control circuit prohibits use of the magneto-optical recording medium, and informs the user of this fact. Write to magneto-optical recording medium.

Therefore, according to the present invention, it is possible to ship a magneto-optical recording medium on which a user can accurately perform a test.

Preferably, each of the plurality of bands includes a test area and a data area, and when a control circuit of the magneto-optical disk device detects a predetermined number or more of defective frames from the data area at random, the magneto-optical recording is performed. The optical pickup and the magnetic head are controlled so that the fact that the medium is prohibited is recorded on the magneto-optical recording medium.

When a predetermined number or more of defective frames are randomly detected in the test in the data area of the test area and the data area constituting the band, the control circuit disables the use of the magneto-optical recording medium and informs the effect to that effect. Write to magnetic recording medium.

Therefore, according to the present invention, a magneto-optical recording medium on which a user can accurately record and / or reproduce a signal can be shipped.

Preferably, when the area for recording the unit data is a line, the control circuit of the magneto-optical disk device
When a predetermined number of lines out of the number of lines constituting one frame include a predetermined number or more of erroneous data, the frame is determined to be a defective frame.

The control circuit determines that a frame is a defective frame when a predetermined number or more of errors are present in the unit data, and when there are a predetermined number or more of lines in which such errors exist.

Therefore, according to the present invention, whether or not a frame is a defective frame can be quickly determined based on a clear criterion.

[0029]

Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding portions have the same reference characters allotted, and description thereof will not be repeated.

With reference to FIG. 1, a description will be given of a magneto-optical recording medium on which data is recorded and / or reproduced by the magneto-optical disk drive according to the present invention. Magneto-optical recording medium 1
00 denotes a plurality of bands B concentrically arranged in the radial direction.
0 to B13. Each of the bands B0 to B13 includes a test area TSR and a data area DR. Test area TS
R is provided on the inner peripheral side of the data area DR. The test area TSR includes three tracks. The track includes one groove and one land adjacent to the groove.

Each band B0 to B13 has a frame (F
Each of the bands B0 to B13 includes a plurality of frames because a signal is recorded and / or reproduced in units of (frame).
That is, referring to FIG. 2, frames as recording units are arranged at equal intervals on the magneto-optical recording medium 100, and each frame has 39 segments (Segmen).
t) S0, S1, S2,..., S38.

The magneto-optical recording medium 100 has a planar structure in which grooves 1 and lands 2 are alternately formed in the radial direction, and the grooves 1 and lands 2 are arranged spirally or concentrically. And the length of each segment is 5
32 DCB (Data Channel Bit), and a fine clock mark (FCM: Fine Clock Mark) 3 indicating phase information of a clock for recording and reproducing data is formed at the beginning of each segment. The fine clock mark 3 is formed by providing lands of a fixed length at regular intervals on the groove 1 and providing grooves of a constant length at regular intervals on the lands 2. Then, in the segment S0 at the head of the frame, following the fine clock mark 3, address information (Address) indicating the address on the magneto-optical recording medium 100 is pre-recorded by the wobbles 4 to 9 when the magneto-optical recording medium 100 is manufactured. Formatted. The magneto-optical recording medium 100 includes preformatted grooves 1, lands 2, fine clock marks 3,
A magnetic layer is formed to cover wobbles 4 to 9. Then, a signal is recorded on the magneto-optical recording medium 100 by irradiating the magnetic layer with a laser beam and applying a magnetic field modulated by a recording signal. In addition, a signal is reproduced from the magneto-optical recording medium 100 by irradiating the magnetic layer with laser light having a predetermined intensity and detecting the reflected light.

Wobbles 4 and 5, wobble 6 and wobble 7, and wobble 8 and wobble 9 are formed on opposite walls of groove 1 and record the same address information. Such a recording method of address information is referred to as a one-sided staggered method, and a tilt or the like occurs in the magneto-optical recording medium 100 by employing the one-sided staggered method,
Even when the laser beam deviates from the center of the groove 1 or the land 2, the address information can be accurately detected.

The area where the address information is recorded and the area where the fine clock mark 3 is formed are not used as areas for recording user data. Segment S
n is the fine clock mark 3 and the user data Use
r Data n-1.

Referring to FIG. 3, a detailed configuration of the segment will be described. Each segment S constituting the frame
0, S1, S2,..., S38, the segment S0 is an address segment preformatted on the magneto-optical recording medium 100, and the segments S1 to S38 are data segments secured as user data recording areas. is there. Segment S0 is 12DCB
The segment S is composed of a fine clock mark area FCM of the
1 is a 12DCB fine clock mark area FCM
, 4DCB Pre-Write, 512DCB Data, and 4DCB Post-Write.

Pre-Write indicates that data is to be written out. For example, the predetermined pattern "001"
The Post-Write indicates the end of the data. For example, the Post-Write indicates a predetermined pattern “1”.
100 ".

The user data area of the segment S1 is provided with a header (Header) which is a fixed pattern for performing data position confirmation during reproduction, position compensation of a reproduction clock, adjustment of laser power, and the like. The fixed pattern to be recorded in the header is a pattern in which a DC component is suppressed (hereinafter, also referred to as a “DC-free pattern”). For example, a fixed pattern in which a predetermined number of 2T domains are formed at intervals of 2T, It records that a predetermined number of domains are formed at intervals of 8T.

Then, phase compensation is performed by adjusting the sampling timing of the analog signal obtained by reproducing the 2T domain so as to match the phase of the clock used for data recording and reproduction, thereby performing the 2T domain and the 2T domain. The 8T domain is reproduced, and the laser power is adjusted so that the ratio of the 2T domain reproduced signal strength to the 8T domain reproduced signal strength becomes 50% or more. Also, by confirming whether or not the position of the digital signal obtained by reproducing the 8T domain and binarizing the reproduced signal matches the position of the digital signal of the 8T domain predicted in advance, the position of the data at the time of reproduction can be confirmed. Do. Further, each pattern of Pre-Write, Post-Write, and Header is recorded continuously with the user data when recording the user data.

The segments S2 to S38 are composed of a 12DCB fine clock mark area FCM and a 4DCB Pr
e-Write, 512DCB Data, 4DC
B-Post-Write.

The preformatted area such as the fine clock mark FCM and the address Address is called a "preformatted area".

In the present invention, a test for detecting a defective frame from a magneto-optical recording medium is performed by using a magneto-optical disk device described later, and the detected defective frame is registered in the magneto-optical recording medium 100. In this case, the test is performed on all the bands B0 to B13 of the magneto-optical recording medium 100 in the order described below.

That is, bands B0 to B13 shown in FIG.
Are tested in the order shown in FIG. That is, the groove 1 and the land 2 are divided into 64 ECC block areas,
The test is performed by repeating the signal recording and the signal reproduction for each C block. A 64 ECC block is a logical block, and one ECC block is 16 blocks.
Equivalent to a frame. And one band is 64E
The number of 64 ECC blocks differs depending on each band.

When recording a signal, 64 of groove 1
The signal “1010110101010” is sent to the ECC block 11.
... ”and then move to land 2 and land 2
The signal “101010101” is sent to the 64 ECC block 12 of
010 ... ”is recorded. And again, groove 1
Is recorded in the 64 ECC block 13 of the groove 1 and the signal "1010101010110 ..." is recorded again.
Move to land 2 and 64 ECC blocks 14 in land 2
Is recorded as a signal "1010110101010 ...".

When reproducing a signal, the signal "10101010101010" is reproduced in the same order as the signal was recorded.
... Are reproduced, and it is determined whether or not each frame is a defective frame according to a criterion for determining a defective frame described later.

Each band B0 to B according to the order shown in FIG.
The test is performed on a plurality of frames included in the frame 13.

Referring to FIG. 5, a magneto-optical disk drive according to the present invention will be described. Magneto-optical disk drive 200
Is a spindle motor 101 and an optical pickup 102
A fine clock mark detection circuit (FCM detection circuit) 103, a PLL circuit 104, an address detection circuit 105, a BPF 106, an AD converter 107, a waveform equalization circuit 108, a Viterbi decoding circuit 109, an unformat Circuit 110, data demodulation circuit 111, and BC
H decoder 112, header detection circuit 113, controller 114, timing generation circuit 115, BCH
It includes an encoder 116, a data modulation circuit 117, a magnetic head drive circuit 123, a laser drive circuit 124, a magnetic head 125, and a format circuit 126.
The format circuit 126 includes a pattern generation circuit 119
And a selector 120.

The spindle motor 101 rotates the magneto-optical recording medium 100 at a predetermined rotation speed. The optical pickup 102 irradiates the magneto-optical recording medium 100 with a laser beam,
The reflected light is detected. The FCM detection circuit 103 detects that the optical pickup 102 detects the fine clock mark detection signal FCMT indicating the position of the fine clock mark 3 on the magneto-optical recording medium 100, and outputs the detected fine clock mark detection signal FCMT to the PLL circuit 104 and the timing. Output to the generation circuit 115.

The PLL circuit 104 includes the FCM detection circuit 10
3 is a fine clock mark detection signal FC
A clock CK is generated based on the MT, and the generated clock CK is used as the address detection circuit 105 and the AD converter 10.
7, output to the waveform equalization circuit 108, Viterbi decoding circuit 109, unformat circuit 110, data demodulation circuit 111, controller 114, timing generation circuit 115, data modulation circuit 117, and pattern generation circuit 119 of the format circuit 126.

The address detection circuit 105 detects the address signal A detected by the optical pickup 102 from the segment S0 of the magneto-optical recording medium 100 by the radial push-pull method.
DA, the address information AD is detected in synchronization with the clock CK input from the PLL circuit 104, and
An address detection signal ADF indicating that the address information AD has been detected is generated at the last position of the address information. Then, it outputs the detected address information AD to the controller 114, and outputs the generated address detection signal ADF to the header detection circuit 113 and the timing generation circuit 115.

The BPF 106 removes the high band and the low band of the reproduction signal RF reproduced from the magneto-optical recording medium 100. A
The D converter 107 receives the clock C from the PLL circuit 104.
The reproduction signal RF is converted from an analog signal to a digital signal in synchronization with K.

The waveform equalizing circuit 108 is a PLL circuit 104
PR (1, 1) waveform equalization is performed on the reproduced signal RF converted into a digital signal in synchronization with the clock CK from the CPU.
That is, the data before and after the detection signal are equalized so as to cause one-to-one waveform interference.

The Viterbi decoding circuit 109 includes a PLL circuit 10
The reproduction signal RF is converted from multi-valued data to binary data in synchronization with the clock CK from Step 4, and the converted reproduction signal RF is output to the unformat circuit 110 and the header detection circuit 113.

The unformat circuit 110 pre-writes (Pre-Write) and post-writes (P) recorded in the user data area of the magneto-optical recording medium 100 in synchronization with the timing signal input from the header detection circuit 113.
ost-Write) and header (Header)
Is removed.

The data demodulation circuit 111 includes the PLL circuit 10
In response to the clock CK from Step 4, an unformatted reproduction signal RF is input, and demodulation is performed to release digital modulation performed during recording.

The BCH decoder 112 corrects the error of the demodulated reproduced signal and outputs it as reproduced data.
The header detection circuit 113 includes the address information AD input from the controller 114 and the address detection circuit 105.
The position of the header included in the reproduction signal is detected based on the address detection signal ADF input from the
4 in synchronization with the clock CK from the playback signal, a pre-write (Pre-Write) and a header (Heade)
r) The timing signal is generated. The generated timing signal of the header is output to the unformat circuit 110 and the data demodulation circuit 111.

The controller 114 receives the address information AD detected by the address detection circuit 105, controls a servo mechanism (not shown) based on the address information AD, and causes the optical pickup 102 to access a desired position. The controller 114 outputs the address information AD to the header detection circuit 113 in synchronization with the clock CK from the PLL circuit 104, and controls the timing generation circuit 115. Further, the controller 114
The number of errors in the reproduced signal is input from the BCH decoder 112,
A defective frame is detected by a method described later.

The timing generation circuit 115 controls the FCM detection circuit 103 based on the control from the controller 114.
Fine clock mark detection signal FCM input from
T and the timing signal SS based on the address detection signal ADF input from the address detection circuit 105, in synchronization with the clock CK input from the PLL circuit 104.
And outputs the generated timing signal SS to the pattern generation circuit 119 and the selector circuit 120 of the format circuit 126, the magnetic head drive circuit 123, and the laser drive circuit 124.

The BCH encoder 116 adds an error correction code to recording data. The data modulation circuit 117 modulates the recording data into a predetermined format. Format circuit 1
Reference numeral 26 denotes a pre-write (Pre-Write), a header (Header), and a recording data from the data modulation circuit 117, which are synchronized with the clock CK from the PLL circuit 104 and based on the timing signal SS from the timing generation circuit 115. And post light (Post-W
write) to format the recording data to match the user data area. Then, the format circuit 126 selectively outputs the formatted recording data and the pattern data to be recorded in the preformat area to the magnetic head drive circuit 123 based on the timing signal SS from the timing generation circuit 115.

The pattern generation circuit 119 outputs the pattern data to be recorded in the pre-format area and the pattern data as pre-write (Pre-Write), header (Header), and post-write (Post-Write) from the PLL circuit 104. Clock (C
K), and outputs the generated data pattern to the selector circuit 120.

The selector circuit 120 selects the recording data from the data modulation circuit 117 and the pattern data from the pattern generation circuit 119 based on the timing signal SS from the timing generation circuit 115, and sends the data to the magnetic head drive circuit 123. Output.

The magnetic head drive circuit 123 drives the magnetic head 125 in synchronization with each timing of the timing signal SS from the timing generation circuit 115 and based on the output from the format circuit 126.

The laser drive circuit 124 drives a semiconductor laser (not shown) in the optical pickup 102 based on the timing signal SS from the timing generation circuit 115.

The magnetic head 125 is driven by a magnetic head driving circuit 123 and applies a magnetic field modulated by recording data or a data pattern to the magneto-optical recording medium 10.
Apply to 0.

Referring to FIG. 6, address information AD and fine clock mark signal F from magneto-optical recording medium 100 are provided.
The detection of the CM and the magneto-optical signal RF will be described.
The area 10 and the area 30 constitute a preformat area that is preformatted when the magneto-optical recording medium 100 is manufactured. In the area 10, wobbles 4 to 7 and a fine clock mark 3 are formed. In the area 30, the fine clock mark 3 is formed. The area 20 constitutes a user data area, in which user data is recorded.

The photodetector 1020 in the optical pickup 102 for irradiating the magneto-optical recording medium 100 with laser light and detecting the reflected light thereof has six detection areas 1020A and 1020A.
0B, 1020C, 1020D, 1020E, 1020
F. Area A1020A and area B1020B, area C1020C and area D1020D, and area E10
The area 20E and the area F1020F are arranged in the tangential direction DR2 of the magneto-optical recording medium 100, and the area A1020
A and the area D1020D, and the area B1020B and the area C1020C are in the radial direction D of the magneto-optical recording medium 100.
It is located at R1.

Areas A1020A, B1020B, C1020C, and D1020D detect reflected light of laser light LB applied to magneto-optical recording medium 100 in areas A, B, C, and D, respectively. I do. Further, a region E1020E and a region F102
0F transmits the laser light reflected by the entire laser light LB in the A region, the B region, the C region, and the D region in two directions having different polarization planes by a Wollaston prism (not shown) of the optical pickup 102. The diffracted laser light is detected.

The reproduction signal RF of the magneto-optical signal recorded in the user data area 20 is composed of the laser light intensity [E] detected in the area E1020E of the photodetector 1020 and the laser light intensity detected in the area F1020F. It is detected by calculating the difference from [F]. That is, the circuit 4
The zero differentiator 400 calculates a difference between the laser light intensity [E] detected in the region E1020E and the laser light intensity [F] detected in the region F1020F, and obtains a reproduction signal RF =
[E]-[F] is output.

Area 10 constituting preformat area
Information AD recorded by wobbles 4 to 7 of
Is detected by the radial push-pull method, and the laser beam intensity [A] detected in the area A1020A
And the sum of the laser beam intensity [C] detected in the region C1020C and the laser beam intensity [D] detected in the region D1020D is subtracted from the sum of the laser beam intensity [B] detected in the region B1020B. Is detected. That is, the address information AD is added to the adder 5 forming the circuit 50.
00, 501 and a subtractor 502. The adder 500 outputs [A + B] obtained by adding the laser light intensity [A] detected in the region A 1020A and the laser light intensity [B] detected in the region B 1020B. Adder 5
01 outputs [C + D] obtained by adding the laser beam intensity [C] detected in the region C1020C and the laser beam intensity [D] detected in the region D1020D. Then, the subtractor 502 subtracts the output [C + D] of the adder 501 from the output [A + B] of the adder 500, and outputs a reproduced signal AD = [A + B] − [C + D] of the address information.

The fine clock mark 3 in the area 30 constituting the preformat area is detected by the tangential push-pull method, and the laser light intensity [A] detected in the area A1020A and the laser light intensity detected in the area D1020D. From the sum with the intensity [D], the area B1020
Laser light intensity [B] detected in B and area C1020C
Is detected as a value obtained by subtracting the sum with the laser light intensity [C] detected in step (1). That is, the fine clock mark signal FCM is added to the adders 503 and 504 constituting the circuit 50.
And a subtractor 505. Adder 503
Is the laser beam intensity [A] detected in the area A1020A.
And [A + D] obtained by adding the laser beam intensity [D] detected in the area D1020D. The adder 504 outputs [B + C] obtained by adding the laser light intensity [B] detected in the region B1020B and the laser light intensity [C] detected in the region C1020C. And the subtractor 505
The output [B + C] of the adder 504 is subtracted from the output [A + D] of the adder 503 to output a fine clock mark reproduction signal FCM = [A + D] − [B + C].

Referring to FIG. 7, the configuration of PLL circuit 104 constituting magneto-optical disk device 200 shown in FIG. 5 will be described. The PLL circuit 104 includes a phase comparison circuit 1041,
LPF 1042 and voltage controlled oscillator (VCO) 1043
And a 1/532 frequency divider 1044. 1/532
The frequency divider 1044 includes a voltage controlled oscillator (VCO) 1043
The clock (CK) output from is divided by 1/532. The phase comparator 1041 is a 1/532 frequency divider 1044
Is compared with the phase of the fine clock mark detection signal FCMT, and an error voltage corresponding to the phase difference is generated. Therefore, this PL
The L circuit 104 outputs the fine clock mark detection signal FC
A clock CK synchronized with MT and having a period of 1/532 of the fine clock mark detection signal FCMT is generated.

Referring to FIG. 8, detection of fine clock mark FCM and generation of clock CK will be described. The light detection unit 1020 of the optical pickup 102 detects the fine clock mark signal FCM by the tangential push-pull method as described with reference to FIG.
M is output to the FCM detection circuit 103. The FCM detection circuit 103 receives the input fine clock mark signal FC.
M based on the fine clock mark detection signal FCMT
Generate That is, in the FCM detection circuit 103, the fine clock mark signal FCM is compared at a predetermined level and converted into a signal FCMC. Then, the signal FCMC is inverted to the signal / FCMC. Thereafter, the rising edge is synchronized with the position of the point P where the polarity of the fine clock mark signal FCM switches, and 6
A detection window signal DEWIN having an amplitude width of DCB is generated, and a logical product of signal / FCMC and detection window signal DEWIN is calculated to generate signal FCMP. Then,
A fine clock mark detection signal FCMT having an amplitude width of 1 DCB synchronized with the rise of the signal FCMP is generated.

The fine clock mark signal FCM in FIG. 8 has been described as a fine clock mark signal detected when the laser beam travels in the groove 1 of the magneto-optical recording medium 100. The fine clock mark signal detected when the laser beam travels on the land 2 only changes its polarity, and the position of the point P does not change. Therefore, even when the laser beam travels on the land 2, the signal FCMP and the fine clock mark detection signal FCMT can be similarly generated.

The FCM detection circuit 103 outputs the detected fine clock mark detection signal FCMT to the PLL circuit 104.
Output to The PLL circuit 104 receives the fine clock mark detection signal FCM as described with reference to FIG.
T and the fine clock mark detection signal F
A clock CK obtained by dividing the CMT by 1/532 is generated.

Referring to FIG. 9, address detection circuit 105
The detection of the address information and the generation of the address detection signal will be described. The optical pickup 102 detects the address signal ADA recorded by wobble by the radial push-pull method as described with reference to FIG. 6, and the address signal ADA is input to the address detection circuit 105. The address detection circuit 105 generates a binarized signal ADD obtained by binarizing the address signal ADA, and detects the address information AD based on the binarized signal ADD. At the same time, the address detection circuit 105 outputs the binary signal A
An address detection signal ADF indicating the final position F of the address signal is generated in synchronization with the clock CK from the PLL circuit 104 based on the DD and the address information AD. The address detection signal ADF is generated by determining a fixed length T including the final position F of the address information. That is, the components from the clock CK component synchronized with the first position of the binarized signal ADD to the clock CK component synchronized with the last position F of the address signal are counted. Then, the count value at the final position F is set to K, and the count value K−
The address detection signal ADF is generated so that a pulse component having a certain length T is generated between m and the count value K + m.

When the magneto-optical recording medium 100 is mounted, all the bands B0 to B13
.. Are recorded, and the recorded signal “1010101010101010.
.. Are reproduced to test which of the plurality of frames is a defective frame.

The data amount of each segment described with reference to FIG. 3 is a data amount in a magneto-optical recording medium according to the AS-MO standard, and is applied to a magneto-optical recording medium having a diameter of 12 cm. Here, the reference of the defective frame will be described using a 2.5 inch diameter magneto-optical recording medium having the same data format as the magneto-optical recording medium according to the AS-MO standard as an example. In a magneto-optical recording medium having a diameter of 2.5 inches, a signal of 2392 bytes is recorded in one frame. Since the recording signal is modulated by the NRZI method, a signal of 2366 bytes is recorded in one frame in consideration of the redundancy in this method. In this magneto-optical recording medium, an area where 182 bytes of data can be recorded is defined as a “line”. Therefore, one frame is composed of 2366/182 = 13 lines. In this case, when a line having a data error of 4 bytes or more exceeds 4 lines, the frame is determined to be a defective frame. This standard is applicable to the magneto-optical recording medium 100 having a diameter of 12 cm.

When the magneto-optical recording medium 100 is mounted, the magneto-optical disk device 200 records a signal “10101010101010...” On the entire magneto-optical recording medium 100. In this case, the signal “10” is added to the address segment.
10101101010... Are not recorded. Then, the optical pickup 102 is connected to the magneto-optical recording medium 100.
Is detected as a magneto-optical signal. The detected magneto-optical signal is supplied to a BPF 106, an AD converter 107,
The above-described processing is performed in the waveform equalization circuit 108, the Viterbi decoding circuit 109, and the unformat circuit 110, and the result is input to the data demodulation circuit 111. Then, the data demodulation circuit 111 demodulates the input reproduction signal,
The CH decoder 112 performs error correction on the reproduced signal,
The number of errors is output to the controller 114.

The controller 114 determines whether or not each frame is a defective frame based on the input number of errors based on the above-described criterion. If it is determined that the frame is a defective frame, the magnetic head driving circuit 123 and the laser driving circuit 124 are controlled via the timing generation circuit 115 so that the number of the defective frame is recorded in the bands B1 and B12 of the magneto-optical recording medium 100. . Then, the timing generation circuit 115 generates a timing signal for recording the number of the defective frame and outputs it to the magnetic head drive circuit 123 and the laser drive circuit 124. Then, the magnetic head 125 and the optical pickup 1
02 is driven, and the number of the defective frame is recorded in bands B1 and B12 of the magneto-optical recording medium 100.

The magneto-optical disk device 200 performs the above-described test on all the bands B0 to B1 of the magneto-optical recording medium 100.
Perform for step 3. The test is performed on the test area TSR and the data area DR of each of the bands B0 to B13.

The controller 114 controls the test area TSR
In, when 16 or more consecutive defective frames exist, it is determined that the use of the magneto-optical recording medium 100 is prohibited, and the fact that the use of the magneto-optical recording medium 100 is prohibited is recorded on the magneto-optical recording medium 100. Controller 1
Reference numeral 14 indicates that when 16 or more frames of defects are randomly present in each of the 64 ECC blocks of the data area DR, the magneto-optical recording medium 100 is determined to be prohibited, and the magneto-optical recording medium 100 is prohibited from being used. The information is recorded on the recording medium 100.

Further, when a clock is not input from the PLL circuit 104 during the above test, for example, during the recording of a signal (this is called “clock abnormality”), the controller 114 controls the magneto-optical disk drive. 200 is forcibly stopped. And the controller 1
14 is when the magneto-optical disk device 200 is re-driven,
Each unit is controlled so as to return to the head of bands B0 to B13 where recording was performed before the forced stop and restart the recording operation. Also, when the signal is forcibly stopped during the reproduction of the signal, the reproduction operation is similarly resumed by returning to the head of the band B0 to B13 which was performing the reproduction operation when the signal was forcibly stopped.

Further, even when the address detection signal ADF is not input from the address detection circuit 105, the controller 114 forcibly stops the magneto-optical disk device 200. Then, when restarting the reproduction operation, the controller 114 determines whether the bands B0 to B
Then, the reproduction operation is resumed by returning to the beginning of the file.

Therefore, when the magneto-optical disk device 200 is forcibly stopped, the controller 114
Since the recording operation or the reproducing operation is resumed by returning to the head of the band accessed at the time of the forced stop, the test can be performed accurately.

The controller 114 is, for example,
Even if the signal is re-recorded five times, the magneto-optical disk drive 200
When is stopped forcibly, the test of the band may be stopped to shift to the next band.

The embodiments disclosed this time are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description of the embodiments, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

[Brief description of the drawings]

FIG. 1 is a plan view of a magneto-optical recording medium.

FIG. 2 is a plan view showing a magneto-optical recording medium and its format.

FIG. 3 is a schematic diagram showing a format of a recording data string.

FIG. 4 is a diagram for explaining the order of tests on grooves and lands.

FIG. 5 is a block diagram of the magneto-optical disk drive according to the embodiment of the present invention.

FIG. 6 is a diagram for explaining reproduction of data from a preformat area and a user data area.

FIG. 7 is a block diagram of a PLL circuit.

FIG. 8 is a timing chart of signals in the FCM detection circuit and the PLL circuit.

FIG. 9 is a diagram for explaining detection of address information and generation of an address detection signal.

[Explanation of symbols]

1 groove, 2 lands, 3 fine clock marks, 4 to 9 wobbles, 10, 30 preformat areas, 20 user data areas, 11 to 14 ECC blocks, 40, 50 circuits, 100 magneto-optical recording medium, 1
01 spindle motor, 102 optical pickup, 1
03 FCM detection circuit, 104 PLL circuit, 105
Address detection circuit, 106 BPF, 107 AD converter, 108 waveform equalization circuit, 109 Viterbi decoding circuit,
110 unformat circuit, 111 data demodulation circuit, 112 BCH decoder, 113 header detection circuit, 114 controller, 115 timing generation circuit, 116 BCH encoder, 117 data modulation circuit, 119 pattern generation circuit, 120 selector circuit, 123 magnetic head drive circuit , 124 laser drive circuit, 125 magnetic head, 126 format circuit, 200 magneto-optical disk drive, 400 differentiator, 5
00, 501, 503, 504 Adder, 502, 50
5 Subtractor, 1020 Photodetector, 1020A, 102
0B, 1020C, 1020D, 1020E, 1020
F region, 1041 phase comparison circuit, 1042 LP
F, 1043 voltage controlled oscillator, 1044 1/532 divider.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G11B 20/18 572 G11B 20/18 572D 572F 576 576C

Claims (7)

[Claims] 1. A magneto-optical disc device for recording and / or reproducing signals on a magneto-optical recording medium, each including a plurality of frames and having a plurality of bands arranged concentrically in a radial direction, An optical pickup for irradiating the magneto-optical recording medium with laser light and detecting reflected light thereof; a magnetic head for applying a magnetic field modulated by a recording signal to the magneto-optical recording medium; A signal processing circuit that performs signal processing on the magneto-optical signal detected from the medium; a defective frame is detected based on the reproduced signal output from the signal processing circuit; and the number of the detected defective frame is stored in the magneto-optical recording medium. A control circuit for controlling the optical pickup and the magnetic head so as to perform recording, the control circuit comprising: When, for controlling the optical pickup and the magnetic head to start recording and / or reproduction of signals from the head of the band, a magneto-optical disk device. 2. A clock generating circuit that generates a clock based on a fine clock mark detection signal that detects a fine clock mark formed on the magneto-optical recording medium, wherein the control circuit is configured to output a clock from the clock generating circuit. 2. The optical pickup and the magnetic head according to claim 1, wherein when an abnormality is input, the optical pickup and the magnetic head are controlled so as to forcibly stop the magneto-optical disk device and start recording and / or reproduction of a signal from the head of a band. Magneto-optical disk device. 3. An address detection circuit for detecting an address of data recorded or to be recorded on the magneto-optical recording medium, wherein the control circuit receives an address non-detection from the address detection circuit. 2. The magneto-optical disk device according to claim 1, wherein the magneto-optical disk device is forcibly stopped, and the optical pickup and the magnetic head are controlled so as to start recording and / or reproducing signals from the beginning of a band. . 4. The optical pickup and the magnetic head so that, when detecting a predetermined number or more of defective frames, the control circuit records on the magneto-optical recording medium that the use of the magneto-optical recording medium is prohibited. 4. The magneto-optical disk drive according to claim 1, wherein 5. The magneto-optical recording medium according to claim 1, wherein each of the plurality of bands includes a test area and a data area, and the control circuit detects a predetermined number or more of defective frames continuously from the test area. 5. The magneto-optical disk drive according to claim 4, wherein the optical pickup and the magnetic head are controlled to record on the magneto-optical recording medium that the use is prohibited. 6. Each of the plurality of bands includes a test area and a data area, and when the control circuit detects a predetermined number or more of defective frames from the data area at random, the magneto-optical recording medium is activated. 5. The magneto-optical disk drive according to claim 4, wherein the optical pickup and the magnetic head are controlled so that the use prohibition is recorded on the magneto-optical recording medium. 7. When the area in which unit data is recorded is a line, the control circuit, when a predetermined number of lines out of the number of lines constituting one frame include a predetermined number or more of error data, Claim 1 to Claim 6
7. The magneto-optical disk device according to claim 1.