JP3416985B2 - Optical disk drive - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc device and an optical rotary recording medium therefor.

[0002]

2. Description of the Related Art A typical sample servo type optical disk or magneto-optical disk is a servo area (servo area) provided at the beginning of each segment on the disk.
A clock pit is formed on the. The clock signal used for reading and writing data is reproduced based on the reproduction signal from the clock pit, and the data is read and written on the disc.

[0003]

The clock pit described above is actually recorded at a position slightly deviated from the position where it should be when recording the clock pit. Therefore, when the clock signal is reproduced based on the reproduced signal from this clock pit, the accuracy of the clock signal becomes low, and as a result, the timing of writing the data is shifted or the timing of reading the data is deviated. However, there was a problem that the reading error of the data occurred.

In order to reduce data reading errors, the accuracy in detecting data from the reproduction signal read from the disk is increased, or the data is decoded using a high-level decoding system such as the Viterbi decoding system. The method of is often taken. However, even if these measures are taken, it is generally known that the error rate of data on an optical disk is worse than that of a magnetic recording medium such as a floppy disk. Moreover, since the amount of hardware required for these measures and the amount of data decoding processing are large, it is difficult to meet the demands for circuit scale reduction, cost reduction, or device reliability improvement.

The optical disc apparatus and the optical rotary recording medium thereof according to the present invention have been made in view of the above-mentioned problems of the prior art, and a clock signal and a clock signal used for reading / writing data from / to the disc. By improving the accuracy of the laser drive signal when writing data to the disc, the reliability of the data recorded on the disc is improved without performing complicated data decoding processing, and the circuit scale is reduced and the cost is reduced. It is an object of the present invention to provide an optical disc device and an optical rotary recording medium for the optical disc device, which can meet the demand for improving the reliability of the device.

[0006]

In order to achieve the above object, the optical disc apparatus of the present invention has a clock signal reproducing pit used for reproducing a clock signal written in advance, and the clock signal reproducing pits are recorded in each predetermined recording range. An optical rotary recording medium having a test writing area in which a test writing pit for correcting a clock signal is written, and data is written by a magneto-optical effect, and the test writing area is formed by the clock signal reproducing pit. Test write pit writing means for writing the test write pits at predetermined positions in the test write area for each of the predetermined recording ranges based on a reproduced clock signal, and test write pits written in the respective test write areas. Is sequentially read, and a timing control hand for correcting the timing of the clock signal based on each of the trial writing pits is read. And an odd number sector and an even number sector are alternately and continuously formed in a recording area of the optical rotary recording medium, and the trial writing area is provided for each sector of the optical rotary recording medium. The test writing area in the optical rotary recording medium has a first set of test writing areas provided in the odd-numbered sectors and a second set of test writing areas provided in the even-numbered sectors. The trial writing pit writing means writes the trial writing pits in the sectors of the one set, the timing control means reads the trial writing pits in the sectors of the one set, and the read trial writing pits are read out. A signal is used to correct the timing of the reproduced clock signal, and the trial write pit writing means is
The test write pits are written in the sectors of the other set using the corrected clock signal, the timing control means reads the test write pits in the sectors of the other set, and uses the read test write pit signals. Then, the timing of the reproduced clock signal is corrected, and the first time of the trial writing area is adjusted until the average value of the time difference between the corrected clock signal and the signal from the trial writing pit falls within a predetermined range. The writing and reading of the trial write pits in the set 1 and the set 2 and the correction of the timing of the clock signal are repeated.

[0007] Preferably, the timing control means is
The timing of the clock signal is corrected so as to minimize the deviation of each time difference between the signal from the test writing pit and the clock signal.

In the optical rotary recording medium, data reading and data writing are performed at different recording frequencies of data in each predetermined range, and the test writing pit writing means is for reproducing the clock signal. The clock signal having a different frequency for each of the predetermined ranges is reproduced based on a pit, the test writing pit is written at a predetermined position in the test writing area based on the clock signal, and the timing control means sets the time difference. ,and,
The timing of the clock signal is corrected based on the information regarding the predetermined range.

In order to achieve the above object, the optical disc apparatus of the present invention has a clock signal reproducing pit used for reproducing a clock signal written in advance and correcting the clock signal for each predetermined recording range. An optical rotary recording medium having a trial writing area in which trial writing pits for writing are written, and at least data is written by a magneto-optical effect; and the trial writing area is reproduced by the clock signal reproducing pits. Based on a clock signal, a test write pit writing unit for writing the test write pits at predetermined positions of the test write area for each of the predetermined recording ranges, and the test write pits written in the respective test write areas are sequentially arranged. A timing system that reads out and corrects the timing of the clock signal based on each of the trial writing pits. Means, and the same number of the trial writing pits are provided corresponding to the clock reproducing pits, and the timing control means controls the signals from the trial writing pits and the signals corresponding to the clock reproducing pits. Based on this, the emission timing of the laser beam used when writing data to the optical rotating medium is controlled.

Preferably, the recording area of the optical rotary recording medium is composed of a plurality of sectors, the test writing area is provided for each sector of the optical rotary recording medium, and the timing control means is provided for the test writing. The emission timing of the laser beam is controlled so as to minimize the deviation of the time difference between the signal from the pit and the clock signal.

Further, the optical rotary recording medium performs data reading and data writing at different recording frequencies of data in each predetermined range, and the trial writing pit writing means is for reproducing the clock signal. The clock signal having a different frequency for each of the predetermined ranges is reproduced based on a pit, the test writing pit is written at a predetermined position in the test writing area based on the clock signal, and the timing control means sets the time difference. ,and,
The emission timing of the laser beam is controlled based on the information regarding the predetermined range.

[0012]

When reading and writing data, a clock signal and a laser drive generated in synchronization with a reproduction signal from a clock pit at a predetermined position in a predetermined recording area of an optical disk, for example, a sector or a segment. A test writing area for writing test writing pits for correcting signals is provided. Based on the information on the time difference between the test writing pits written in this test writing area and the clock signal, etc., the clock signal and each storage area of each recording area are
The clock signal or the like is corrected so that the deviation of the trial writing pits is minimized. With the above operation, the timing of the clock signal and the like in each recording area is optimized to improve the reliability when reading and writing data, and complicated decoding processing is unnecessary.

[0013]

EXAMPLE A first example of the present invention will be described below. FIG. 1 is a diagram showing the configuration of an optical disc device 1 of the present invention. In the optical disc device 1 of the present invention, the disc 10 is provided with a trial writing area (trial writing area) for recording trial writing pits for correcting a clock signal used for reading and writing data for each sector. The optical disc device 1 writes a trial writing pit at a position determined based on a clock signal, then reads out the trial writing pit in each trial writing area, and varies the time difference (phase difference) between the reproduction signal and the clock signal. By optimizing the clock signal so as to minimize, the phase of the clock signal and the like are optimized.

In FIG. 1, a disk 10 is a sample servo type magneto-optical disk in which data is written and data is optically read by a magneto-optical effect. As will be described later with reference to FIG. 3, the disk 10 is provided with a test writing area for each sector, and the time difference (phase difference) between the test writing pits written in this area and the clock signal is detected, and this time difference is detected. The clock signal is corrected based on the information.

The control circuit 6 is composed of, for example, a general-purpose microprocessor or the like, and controls each part of the optical disc device 1. The connection between the control circuit 6 and each part of the optical disc device 1 is omitted for simplification of the drawing. The spindle motor 11 rotates the disk 10 under the control of the spindle control circuit 12. Spindle control circuit 12
Controls the spindle motor 11 according to an instruction from the control circuit 15. The optical system 13 is a laser light emitting element, 4
Split light receiving element, lens, tracking coil, and
A laser beam is emitted from the laser light emitting element to the disk 10, which is composed of a focus coil and the like, and the reflected light ray is converted into an electrical reproduction signal by the four-division light receiving element and input to the IV conversion matrix 14. The IV conversion matrix 14 converts the reproduction signal input from the optical system 13 into current / current.
The voltage conversion (I / V conversion) is performed to obtain a focus error signal and a sum signal, which are input to the PLL circuit 4, the A / D conversion circuit 16, and the servo control circuit 15, respectively.

The PLL circuit 4 includes an IV conversion matrix 14
A clock signal synchronized with the sum signal corresponding to the clock pit on the disk 10 is generated based on the sum signal input from the recording control circuit 5 and the recording timing adjustment signal input from the recording control circuit 5. Although the clock signal is used in each part of the optical disc device 1, some of the connections are omitted for simplification of the drawing. A / D conversion circuit 16
Performs digital / analog (A / D) conversion of the sum signal input from the IV conversion matrix 14. The timing signal generation circuit 17 generates a data detection position signal and a wobble pit position signal indicating a time difference between the clock signal and the sum signal corresponding to the trial writing pit, based on the clock signal input from the PLL circuit 4, The data is input to the data detection circuit 18 and the tracking error generation circuit 17, respectively.

The data detection circuit 18 detects data based on the data detection position signal input from the timing signal generation circuit 17 and the sum signal converted into a digital signal by the A / D conversion circuit 16. The tracking error generation circuit 19 includes a timing signal generation circuit 17
Wobble pit position signal input from and A /
The D conversion circuit 16 detects a tracking error with respect to the track on the disk 10 based on the sum signal converted into a digital format signal, and inputs it to the servo control circuit 15 as a tracking error signal. The servo control circuit 15 includes a tracking error generation circuit 19
The tracking error signal input from
A focus coil drive signal and a tracking coil drive signal are generated based on the focus error signal input from the conversion matrix 14, and the optical system 13 is controlled to perform tracking control and focus control on the disk 10. The magnetic head 20 converts the magnetic head drive signal input from the laser / magnetic head control circuit 3 into a magnetic signal and applies it to a desired portion of the disk 10 to record data.

The recording control circuit 5 performs processing such as speed conversion of recording data to be recorded on the disk 10 at the time of writing data, and inputs it to the laser / magnetic head control circuit 3 as a recording signal. Further, the recording timing adjustment signal is generated based on the signal waveform of the sum signal corresponding to the trial writing pit input from the data detection circuit 18, and the PLL circuit 4
To control the timing of the clock signal. The laser / magnetic head control circuit 3 generates a laser drive signal and a magnetic head drive signal based on the recording control signal input from the recording control circuit 5, and controls the optical system 13 and the magnetic head 20. Here, when writing data to the disk 10, a laser beam is applied to a desired portion of the disk 10 from the optical system 13 to apply heat, and a recording signal converted into a magnetic signal from the magnetic head 20 is applied. Then, the direction of the magnetic field of the recording material in this portion is changed to write data. Further, when reading data from the disc 10, a laser beam from the optical system 13 is applied to a desired portion, and the reflected laser beam changed by the interaction with the recording material of the disc 10 is received by the optical system 13 to read the data. I do.

FIG. 2 is a diagram showing the configuration of the recording control circuit 5. In FIG. 2, the differential signal generation circuit 51 generates a differential signal of the sum signal corresponding to the trial writing pits input from the data detection circuit 18. The peak detection circuit 52 is
Based on the output signal of the differential signal generation circuit 51, the peak position of the waveform of the sum signal corresponding to the trial writing pit is detected. Specifically, the peak position of the sum signal is detected by detecting the position where the voltage of the differential signal is 0V. The position information addition circuit 53 detects a time difference between the drive pulse of the laser light emitting element of the optical system 13 and the position of the peak of the waveform of the sum signal corresponding to the trial writing pit, and outputs a predetermined number of this time difference information (position information). to add. Averaging circuit 54
Calculates the average value by dividing the added value of the position information calculated by the position information addition circuit 53 by the predetermined number. The average value deviation circuit 55 calculates a variation (deviation) in the average value of the position information calculated by the averaging circuit 54, and generates a clock signal at a timing that minimizes this deviation.
A fine adjustment signal for controlling the L circuit 4 is generated and input to the recording timing adjustment circuit 58. The comparison circuit 56 compares the reference data of the average value set in the recording position setting circuit 57 with the average value calculated by the average value deviation circuit 55 to generate a rough adjustment signal, and inputs it to the recording timing adjustment circuit 58. . In the recording position setting circuit 57, the reference data of the average value calculated by the averaging circuit 54 is set by the control circuit 6.
The reference data is referred to by the comparison circuit 56 at any time. The recording timing adjustment circuit 58 uses the coarse adjustment signal and the fine adjustment signal input from the comparison circuit 56 to set the PL
A signal for controlling the L circuit 4 is generated. The recording data processing circuit 59 performs processing such as speed conversion on the input recording data and inputs it as a recording signal to the laser / magnetic head control circuit 3. Each part of the recording control circuit 5 may be configured as independent hardware, or may be configured as software on the same computer.

FIG. 3 is a diagram showing the position of the trial writing area provided in each sector of the disk 10. In FIG. 3, (A) shows the structure of the sector, and (B) shows the waveform of the sum signal corresponding to the sector mark of the address segment and the waveform of the sum signal corresponding to the test writing pits of the trial writing area. The trial writing area does not have to be located at the end of the sector, and can be placed at any position. As shown in FIG. 3A, the leading segment of each sector is used as an address segment, and a sector mark is recorded in this address segment. Also,
The test writing area is provided at the end of each sector, and the optical disk device 1 writes the test writing pit at a predetermined position determined based on the clock signal in the test writing area. The sector mark and the trial writing pit are sequentially read out, and are read in the IV conversion matrix 14 as shown in FIG.
The sum signal is generated as shown in FIG. The clock signal is generated in synchronization with the sum signal corresponding to the sector mark, and the time difference between this clock signal and the peak of the sum signal corresponding to the trial writing pit is detected as position information. The optical disc device 1 also reads out the signals recorded in the sector mark and the trial writing area for generation of a clock signal and correction thereof when writing data.

Here, the relationship between tracks, sectors, and segments will be described. 4 shows tracks, sectors,
It is a figure which shows and the relationship of a segment. In FIG. 4, (A) shows a track configuration and (B) shows a sector configuration. As shown in FIG. 4A, the track is composed of a plurality of sectors. Further, as shown in FIG. 4B, the sector is composed of a plurality of segments,
The first segment of the sector is used as an address segment in which address information is recorded, and the other segments are used as data segments used for recording data. Each segment is further divided into a servo area and a data area, a signal used for clock reproduction and the like is recorded in the servo area, and data to be originally recorded is recorded in the data area.

FIG. 5 is a diagram for explaining the operation when the recording control circuit 5 detects position information. In FIG. 5, (A) is a pulse waveform of a laser drive signal generated based on a clock signal, (B) is a waveform of a sum signal corresponding to a trial writing pit, and (C) is a sum signal corresponding to a trial writing pit. , And (D) is a position information signal.
The sum signal waveforms and their differential waveforms shown in FIGS. 5B and 5C are digital format signals converted into digital format signals by the A / D conversion circuit 16, but for convenience of explanation, they are of analog format. It is represented as a signal. Figure 5 (A)
The laser drive signal shown in is generated based on the clock signal and is synchronized with the clock signal. The laser light emitting element of the optical system 13 emits light when writing data to the disk 10, for example, when the laser drive signal has a logical value of 1, and stops emitting light when it has a logical value of 0. The sum signal from the trial writing pits recorded in the trial writing area shown in FIG. 5B is converted into the differential signal shown in FIG. 5C in the differential signal generating circuit 51, and in the peak detecting circuit 52,
This differential signal is shown by b in FIG.
The position where the voltage becomes 0 V (zero cross point) is detected.
In the position information adding circuit 53, as shown in FIG. 5D, the time difference between the rising point of the laser drive signal shown in FIG. 5A and the zero cross point of the differential signal of the sum signal corresponding to the trial writing pit. Is detected as position information. That is, it is possible to detect the time difference between the peak of the clock signal and the peak of the sum signal corresponding to the test writing pit via the laser emission signal that defines the emission timing of the laser emission element of the optical system 13.

The operation of the optical disc device 1 will be described below. The disk 10 is rotated by a spindle motor 11. The optical system 13 and the magnetic head 20 access a predetermined position of the rotating disk 10 to write and read data. When reading the data of the disk 10, the laser / magnetic head control circuit 3 causes the laser light emitting element of the optical system 13 to emit light with a predetermined light amount,
The disk 10 is irradiated with the reflected laser beam, which is input to the IV conversion matrix 14. The sum signal and the focus error signal are generated in the IV conversion matrix 14, and are input to the PLL circuit 4, the A / D conversion circuit 16, and the servo control circuit 15.

The servo control circuit 15 generates a focus coil drive signal for the optical system 13 and a tracking coil drive signal based on the focus error signal to perform focus control and tracking control. On the other hand, the PLL circuit 4 generates a clock signal based on the sum signal. The timing of the clock signal is controlled by the recording control circuit 5 based on the sum signal corresponding to the write pits, as described later. Timing signal generation circuit 1
Reference numeral 7 is a timing used in each part of the optical disc device 1 such as a wobble pit position signal and a data detection position signal based on a clock signal and a sum signal corresponding to wobble pits recorded in the servo area of each segment. Generate a signal. The disk 10 converts the sum signal into a digital format signal, detects the data of the converted sum signal based on the data detection position signal input from the timing signal generation circuit 17, and outputs it as reproduction data. The tracking error generation circuit 19 generates a tracking error signal based on the wobble pit position signal generated by the timing signal generation circuit 17, and inputs it to the servo control circuit 15.

At the time of writing the data, the recording control circuit 5 performs various processes such as data speed conversion on the input recording data and inputs it as a recording signal to the laser / magnetic head control circuit 3. At this time, a signal for recording the trial writing pits recorded in the trial writing area is added to the recording signal at a predetermined timing. The laser / magnetic head control circuit 3 generates a laser drive signal and a magnetic head drive signal based on the recording signal, and the optical system 1
The laser light emitting element 3 and the magnetic head 20 are controlled. Also, when data is read out, the signals in the servo areas of the respective segments of the disk 10 are read out, and clock signals are generated in the respective parts of the PLL circuit 4 and the like.

The timing control of the clock signal by the recording control circuit 5 will be described below. The sample servo method, in particular, the disk is divided into multiple areas in the radial direction in order to improve the storage capacity per disk, and the frequency at which data is recorded and reproduced is changed in each area, that is, at the high frequency in the outer area. MCAV (Modified CAV) for reading / writing data and reading / writing data at a low frequency in the inner area
In the method, since the frequency of the clock signal is different in each area, the timing of the clock signal and the recording pit for recording the data easily deviates. On the other hand, in the sample servo system, a stable clock signal is generated based on the servo signal recorded in the servo area provided in each segment. The recording control circuit 5 detects the positional deviation of the recording pits using this stable clock signal and controls the timing of the clock signal.

First, the recording control circuit 5 generates a signal for recording a trial writing pit, and the optical system 13 and the magnetic head 20 are generated via the laser / magnetic head control circuit 3.
The test writing pits are recorded at a predetermined timing in the test writing area provided in each sector on the basis of the clock signal. Next, the trial writing pits in this trial writing area are read out, differentiated by the differential signal generation circuit 51, the peak position of the waveform is detected by the peak detection circuit 52, and the clock signal and the trial writing pits are detected by the position information adding circuit 53. The position information is detected from the time difference between the peaks of the sum signals corresponding to, and this position information is added by a predetermined number.
An average value is calculated in the averaging circuit 54 from the added value. This average value is compared with the reference data recorded in the recording position setting circuit 57 in the comparison circuit 56, and a coarse adjustment signal is generated based on this result. On the other hand, in the average value deviation circuit 55, the variation of the average value calculated by the average circuit 54 is calculated, and the fine adjustment signal is generated.

The reference data is set in several steps, for example, and the comparison circuit 56 outputs a coarse adjustment signal corresponding to the average value calculated by the averaging circuit 54, and the position information is output via the recording timing adjustment circuit 58. P so that the average value approaches a predetermined value corresponding to the known data writing position
It controls the LL circuit 4 and adjusts the timing of the clock signal. Further, the average value deviation circuit 55 generates a fine adjustment signal so that the deviation of the average value is reduced, and the PLL circuit 4 is controlled so that the average value of the position information approaches a predetermined value via the recording timing adjustment circuit 58. Control and adjust the timing of the clock signal. By controlling the PLL circuit 4 via the average value deviation circuit 55 and the recording timing adjustment circuit 58 of the comparison circuit 56 described above, the clock signal of the optical disk device 1 is the sum signal corresponding to the trial writing pits. Is within a predetermined range with respect to the peak of, and is most average with respect to each test writing pit, that is, the phase relationship with the smallest deviation as a whole with respect to the position where the pit is to be written is optimized.

The second part of the optical disk device of the present invention will be described below.
An example will be described. In the second embodiment, as in the first embodiment, the PLL circuit 4 reproduces the clock signal from the sum signal corresponding to the sector mark and the sum signal corresponding to the trial writing pits written in the trial writing area. The peak is detected and the timing of the clock signal is corrected.

FIG. 6 is a diagram showing the configuration of the PLL circuit 40 in the second embodiment. PL in the second embodiment
The L circuit 40 is to be replaced with the PLL circuit 4 of the optical disc device 1 of the first embodiment, and in this case, the recording control circuit 5 except for the recording data processing circuit 59 is omitted. Is used.

In FIG. 6, the preformat signal detection circuit 41 detects the sum signal corresponding to the sector mark,
Input to the multiplication circuit 43. Trial write signal detection circuit 42
Detects the sum signal corresponding to the trial writing pit written in the trial writing area and inputs it to the multiplication circuit 43. The multiplication circuit 43 multiplies the output signal of the pre-format signal detection circuit 41 and the output signal of the trial write signal detection circuit 42. By the multiplication in the multiplication circuit 43, the sum component and the difference component of the frequencies of these signals are detected. LP
The F44 passes a component having a frequency equal to or lower than a predetermined frequency of the output signal of the multiplication circuit 43 and inputs it to the recording clock phase control circuit 46. Multiplication in the multiplication circuit 43 and LPF4
By the filtering in 4, the difference component between the frequency of the output signal of the preformat signal detection circuit 41 and the frequency of the output signal of the trial write signal detection circuit 42 is output. When these signals are accurately synchronized, the value of the output signal of the LPF 44 becomes maximum, and the phase difference between these signals is detected as the phase change of the output waveform. The output signals of the pre-format signal detection circuit 41 and the trial write signal detection circuit 42 are required to have the same frequency, and it is necessary that these are recorded in the same sector at the same frequency. If this condition is satisfied, the clock pits in the servo areas of the segments are detected by the pre-format signal detection circuit 41, the test writing areas are provided in each segment in association with this, and the test writing pits are written. The clock signal may be corrected based on the above.

The phase comparator circuit 45 compares the position phase of the clock signal and the sum signal generated by the PLL circuit 40 detects these differences are input to the recording clock phase control circuit 46. The recording clock phase control circuit 46 generates a control voltage signal for controlling the VCO 47 based on the output signals of the LPF 44 and the phase comparison circuit 45, and inputs it to the VCO 47. V
The CO (voltage control oscillation circuit) 47 generates a clock signal having a frequency and a phase corresponding to the control voltage signal input from the recording clock phase control circuit 46. In the recording clock phase control circuit 46, by controlling the VCO 47 in the direction in which the output signal of the LPF 44 becomes maximum,
It is possible to optimize the timing of the sum signal and the clock signal corresponding to the trial writing pit.

The third embodiment of the optical disc device of the present invention will be described below.
An example will be described. The optical disk device of the third embodiment optimizes the pit position when writing data by controlling the timing of the laser drive signal. Figure 7
FIG. 9 is a diagram showing a configuration of a laser / magnetic head control circuit 30 in a third embodiment.

The laser / magnetic head control circuit 30 replaces the laser / magnetic head control circuit 3 in the first embodiment, and the recording control circuit 5 of the optical disk device 1 is the same as the recording data processing circuit 59. The one with the part omitted is used. In FIG. 7, the pit center position detection circuit 31 detects the center position of the trial writing pit with reference to the clock signal. The detection of the center position is performed by detecting the peak position of the sum signal, as described in the first embodiment. Timing signal generation circuit (T
G) 33 generates a pit position signal indicating the position of the pit within a predetermined range of the MCAV type magneto-optical disk based on the zone information set by the control circuit 6 and inputs it to the position comparison circuit 32. . Since the position where the pit should be generated at the time of writing the data is uniquely determined by the clock signal and the area for writing, the pit position signal can be generated in the timing signal generation circuit 33. The position comparison circuit 32 compares the pit position signal input from the timing signal generation circuit 33 with the information on the center position of the trial writing pit input from the pit center position detection circuit 31. The laser emission timing generation circuit 34 generates a laser drive signal based on the comparison result of the timing signal generation circuit 33.

Of the data input from the data detection circuit 18, the pit center position detection circuit 31 detects the position of the trial writing pit, and the position comparison circuit 32 further detects the center position of the trial writing pit and the pit position signal. Deviation is detected. The position comparison circuit 32 controls the laser emission timing generation circuit 34 so as to minimize the deviation between the center position of the trial writing pit and the pit position signal, and generates the laser drive signal. By controlling and optimizing the timing of the laser drive signal as described above, it is possible to form the pit at the position where the data recording pit should originally be.

The fourth embodiment of the optical disk device of the present invention will be described below.
An example will be described. The optical disk device of the fourth embodiment is a modification of the optical disk device shown in the third embodiment, and is a set of two or more sectors on the disk 10, for example, an even-numbered sector and an odd-numbered sector. The test writing pits are alternately read from these groups and the positions of the pits formed when data is recorded are corrected.

FIG. 8 is a diagram showing the configuration of the laser / magnetic head control circuit 38 of the fourth embodiment. The laser / magnetic head control circuit 38 replaces the laser / magnetic head control circuit 30 shown in the third embodiment.
In FIG. 8, the position detection circuit 35 is the data detection circuit 1
With respect to the output signal of No. 8, based on the pit position information input from the timing signal generation circuit 33, all the trial write pits of the odd numbered sectors on the same sector are detected, and then the test write pits of the even numbered sectors are detected. For example, the difference between the trial writing pit on the same sector and the pit position information is alternately detected, and is input to the averaging circuit 36. The averaging circuit 36 sequentially averages a predetermined number of pieces of difference information detected by the position detection circuit 35, and inputs the result to the control signal generation unit 37. The control signal generation unit 37 generates a control signal based on the average value calculated by the averaging circuit 36, and inputs the control signal to the laser emission timing generation circuit 34.
It should be noted that each part of the laser / magnetic head control circuit 38 not described here is the laser / magnetic head control circuit 30.
Is the same for each part of the same reference numeral.

The operation of the laser / magnetic head control circuit 38 will be described below with reference to FIG. FIG. 9 is a diagram for explaining the operation of the optical disc device of the fourth embodiment. In FIG. 9, (A) shows sectors k to k + 3, and (B).
(E) to (E) show clock signals corresponding to sectors k to k + 3 and sum signals corresponding to test writing pits, respectively. However, k is an odd number here. The control circuit 6 controls each part of the optical disk device 1 to write the test writing pits in the test writing areas of every other sector, for example, in the odd numbered sectors. At this time, no trial write pit is written in the even-numbered sectors. In the position detection circuit 35, the average value of the time differences (x1, x3 ... In FIGS. 9B and 9D) between the peak of the sum signal corresponding to the trial writing pits in the odd sector and the laser drive signal is averaged. The control signal generation unit 37 controls the laser emission timing generation circuit 34 based on the average value calculated by the digitization circuit 36, and the positions of the trial writing pits with respect to the even pits (shown in FIGS. 9C and 9E). x2, x4 ...) is obtained, and trial writing pits are written in even-numbered sectors.

After the first time, trial writing pits are present in each sector. In this case, the trial writing pits are overwritten. The above operation is alternately performed for the odd-numbered sector and the even-numbered sector, writing of the trial write pits and the laser driving signal until the average value calculated by the averaging circuit 36 falls within a predetermined value. Perform timing correction.

In the optical disc device and the optical rotary recording medium thereof according to the present invention, for example, as shown in FIG. 10, a trial writing area is provided for each segment, and the trial writing pit and the clock signal are corrected in each segment. You can FIG. 10 is a diagram showing a structure of a segment. Figure 1
0, (A) shows the structure of the segment, (B)
Shows the waveform of the sum signal corresponding to the clock pit and the trial writing pit, and (C) shows the clock signal,
(D) shows a laser drive signal.

As shown in FIG. 10A, the head of each segment is used for the servo area, and the tail of the segment is used for the trial writing area. 10 (B), (C)
As shown in, the phase difference between the peak of the sum signal and the clock corresponding to the trial writing pit is the number of clocks of the clock signal m.
And the phase difference α, and can be used for the timing correction in each of the above-described embodiments. Further, as shown in FIG. 10D, since the phase difference β between the laser driving signal and the clock signal is known, the laser driving signal can be generated based on the clock signal. In addition to the above, among the respective parts of each embodiment, a part which can be configured by software on a computer is included in the control circuit 6, or the correction for the clock signal and the correction for the laser drive signal are combined. The optical disc device and its optical rotary recording medium can have various configurations.

[0042]

As described above, according to the optical disk device and the optical rotary recording medium of the present invention, the test writing pits are written in a predetermined test writing area, and the test writing pits are read out to obtain the clock signal. By correcting the timing of the laser drive signal, it is possible to accurately determine the position of the pit formed when writing data on the magneto-optical disk. Further, it is possible to optimize the position of the trial writing pit by sequentially repeating the writing of the trial writing pit and the correction of the position thereof, and to further optimize the timing of the clock signal and the laser drive signal. Is possible.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an optical disc device of the present invention in a first embodiment.

FIG. 2 is a diagram showing a configuration of a recording control circuit of the optical disc device shown in FIG.

3 is a diagram showing a position of a trial writing area provided in each sector of the disc shown in FIG.

4A and 4B are diagrams showing the relationship between tracks, sectors, and segments of the disk shown in FIG. 1, where FIG. 4A is a track configuration and FIG. 4B is a sector configuration.

5A and 5B are diagrams illustrating an operation when position information is detected in the recording control circuit shown in FIGS. 1 and 2, in which FIG. 5A shows a laser drive signal generated based on a clock signal. The pulse waveform, (B) the waveform of the sum signal corresponding to the trial writing pits, (C) the differential waveform of the sum signal corresponding to the trial writing pits, and (D) the position information signal.

FIG. 6 is a diagram showing a configuration of a PLL circuit according to a second embodiment.

FIG. 7 is a diagram showing a configuration of a laser / magnetic head control circuit according to a third embodiment.

FIG. 8 is a diagram showing a configuration of a laser / magnetic head control circuit according to a fourth embodiment.

FIG. 9 is a diagram for explaining the operation of the optical disk device of the fourth embodiment, in which (A) shows a sector and (B)-
(E) shows a clock signal corresponding to the sectors k to k + 3 and a sum signal corresponding to the trial writing pits.

FIG. 10 is a diagram showing a configuration of a segment when a test writing area is provided for each segment, FIG. 10A shows a configuration of the segment, and FIG. 10B corresponds to a clock pit and a trial writing pit. Shows the waveform of the sum signal,
(C) shows a clock signal, (D) shows a laser drive signal.

[Explanation of symbols]

1 ... Optical disc device, 10 ... Disc, 1
1 ... Spindle motor, 12 ... Spindle control circuit, 13 ... Optical system, 14 ... IV conversion matrix, 15 ... Servo control circuit, 16 ... A
/ D conversion circuit, 17 ... Timing signal generation circuit, 1
8 ... Data detection circuit, 19 ... Tracking error generation circuit, 20 ... Magnetic head, 3, 30, 38 ...
..Laser / magnetic head control circuit, 31 ... Pit center position detection circuit, 32 ... Position comparison circuit, 33 ...
・ Timing signal generation circuit, 34 ... Laser emission timing generation circuit, 35 ... Position detection circuit, 36 ...
・ Averaging circuits 36, 37 ... Control signal generating units 4, 4
0 ... PLL circuit, 41 ... Pre-format signal detection circuit, 42 ... Trial writing signal detection circuit, 43 ...
-Multiplication circuit, 44 ... LPF, 45 ... Phase comparison circuit, 46 ... Recording clock phase control circuit, 47 ...
VCO, 5 ... Recording control circuit, 51 ... Differential signal generation circuit, 52 ... Peak detection circuit, 53 ... Position information addition circuit, 54 ... Average circuit, 55 ... Average value deviation Circuit, 56 ... Comparison circuit, 57 ... Recording position setting circuit, 58 ... Recording timing adjusting circuit, 59 ...
Recording data processing circuit, 6 ... Control circuit

Claims (6)

(57) [Claims] 1. A clock signal reproducing pit used for reproducing a clock signal is written in advance, and a test writing area is provided in which a test writing pit for correction of the clock signal is written for each predetermined recording range. An optical rotary recording medium on which data is written by a magnetic action, and the test writing area, the test writing area for each of the predetermined recording ranges based on a clock signal reproduced by the clock signal reproducing pits. Test writing pit writing means for writing the test writing pits at predetermined positions, and the test writing pits written in the respective trial writing areas are sequentially read out, and the timing of the clock signal is corrected based on the respective trial writing pits. The recording area of the optical rotary recording medium has an odd-numbered sector and an even-numbered sector. And the test writing area is provided for each sector of the optical rotary recording medium, and the test writing area in the optical rotary recording medium is provided in the odd-numbered sector. The test writing area is defined as a first set of test writing areas and a second set of test writing areas provided in the even-numbered sectors. The timing control means reads out the trial write pits in the sectors of the one set and corrects the timing of the reproduced clock signal using the read trial write pit signal. The writing means writes a test writing pit in the sector of the other set using the corrected clock signal, The control means reads out the trial writing pits in the other set of sectors, corrects the timing of the reproduced clock signal using the read trial writing pit signal, and corrects the clock signal and the trial writing. Until the average value of the time difference from the signal from the pit falls within a predetermined range, writing and reading of the trial writing pits in the first set and the second set of the trial writing area, and the timing of the clock signal Optical disc device that repeats correction. 2. The optical system according to claim 1, wherein the timing control means corrects the timing of the clock signal so as to minimize the deviation of each time difference between the signal from the trial writing pit and the clock signal. Disk device. 3. The optical rotary recording medium performs data reading and data writing at different recording frequencies of data for each predetermined range, and the test writing pit writing means is for reproducing the clock signal. The clock signal having a different frequency for each of the predetermined ranges is reproduced based on a pit, and the test writing pit is written at a predetermined position of the test writing area based on the clock signal. and, an optical disk apparatus according to the correction of the timing of the clock signal on the line cormorants 請 Motomeko 1 or 2 based on the information regarding the predetermined range. 4. A test writing area in which a clock signal reproducing pit used for reproducing a clock signal is written in advance, and a test writing pit for correction of the clock signal is written for each predetermined recording range, An optical rotary recording medium on which data is written by a magnetic action, and the test writing area, the test writing area for each of the predetermined recording ranges based on a clock signal reproduced by the clock signal reproducing pits. Test writing pit writing means for writing the test writing pits at predetermined positions, and the test writing pits written in the respective trial writing areas are sequentially read out, and the timing of the clock signal is determined based on the respective trial writing pits. The test writing pit corresponds to a clock reproduction pit. A plurality of the timing control means are provided for emitting the laser beam used when writing data to the optical rotary medium based on the signal from the trial writing pit and the signal corresponding to the clock reproducing pit. Optical disc device that controls timing. 5. A recording area of the optical rotary recording medium is composed of a plurality of sectors, the test writing area is provided for each sector of the optical rotary recording medium, and the timing control means is configured to perform the trial writing pits. 5. The optical disk device according to claim 4, wherein the timing of emission of the laser beam is controlled so as to minimize the deviation of each time difference between the signal from the laser and the clock signal. 6. The optical rotary recording medium performs data reading and data writing at different recording frequencies of data for each predetermined range, and the test writing pit writing means is for reproducing the clock signal. The clock signal having a different frequency for each of the predetermined ranges is reproduced based on a pit, and the test writing pit is written at a predetermined position of the test writing area based on the clock signal. , And the optical disc device according to claim 4 or 5, which controls the emission timing of the laser beam based on information regarding the predetermined range.