JPH0442442A - Address detecting system for optical disk memory device - Google Patents

Abstract

PURPOSE:To prevent a sector address missed by detecting an address conforming to reflected light at every beam of plural beam irradiation means arranged in the rotating direction of an optical disk and capable of performing operations independently, and executing the sequence of a recording/reproducing operation by using the address decided as correct. CONSTITUTION:The optical head 51 which completes erasure, recording, and reproduction within one time of revolution of a disk by using three beams of erasure, recording, and reproduction arranged along the rotating direction is assembled, and the intensity of the reflected light of the three beams from a magneto-optical disk medium 50 can be obtained by reflected light quantity detectors 53-55, and they are inputted to address detection circuits 60-62, respectively. A controller 65 performs such control that each operating sequence of the erasure, recording, and reproduction can be executed by using the address when at least one correct address exists in readout addresses obtained from the address detection circuit 60-62 and normal/defect condition decision information. Thereby, it is possible to reduce a missing ratio for the sector address.

Description

Detailed Description of the Invention <Industrial Utilization Public Expense> The present invention is a method for detecting sector addresses within a unit track recorded on an optical disk medium for upper storage, and in particular, a method for detecting a sector address within a unit track recorded on an optical disk medium for upper storage. The present invention relates to an address detection method suitable for use in an optical disk storage device that performs operations.

<Prior Art> In an optical disk storage device, a fixed address system is used for the optical disk medium, and data can only be recorded or reproduced by reading an address at a predetermined position on the optical disk medium.

Address reading 9 involves detecting and reading out a predetermined address by detecting and reading a predetermined address based on changes in the amount of reflected light due to the unevenness, since the addresses on the optical disk medium, such as track addresses and sector addresses, are preformatted with unevenness.

As a representative example of the format of the address portion of an optical disc medium, FIG. 3 shows the 130 standard for a 130 m diameter optical disc medium for information storage. In this Figure 3,
1 is the entire preformat area, 2 is the sector mark (S
M), 3, 6, 9 are VFO(Verified
FrequencyOseillator)
4, 7, 10 are address marks (AM), 5, 8.
11 is an address (ADD) and a cyclic check code (CRCC:
Cyelie Redundancy CheekC
Of the preformat area 1 created at the beginning of each sector during manufacturing of the optical disk medium, the first 8M2 is a special pattern that provides an opportunity to create various reference gate signals. In other words, in 8M2, the formed unevenness is recorded for a long time (recorded at low recording density), and when detecting a large number of these unevenness, majority voting logic is used to detect it, and when determining whether or not 3M2 is possible, the detection rate and accuracy are I'm making adjustments.

On the other hand, in preformat area 1, the combinations VFO mark'), AM, and ADD+CRCC are repeated three times in a row, and are made redundant by doing them three times in a row mainly to eliminate the influence of medium defects. Among these, VFO mark 3,
In 6°9, synchronization is achieved, and in AM4 and 7.10, there is a clear break with the address. This AM4? , 10 are special patterns that do not follow the rules of the modulation method used, so even if 8M2 is not detected, AM4, 7.1
It is possible to read the address using 0 as a trigger. The address ADD consists of a track address (2 bytes) and a sector address (1 byte), followed by
It is accompanied by a CRCC that checks for address errors.

In this way, in the conventional format of the address part, 8M2, AM4, 7, and 10 are used as triggers for address detection, and the address itself is ADD5, 8, 11, and 3.
The formatting is extremely clever, including overwriting.

<Am to be solved by the invention> However, even if formatting is performed in this way, the detection state of the sector address obtained from the reflected light of the reproduction beam is not necessarily stable in practical use, and there are problems with data reliability. The bowl is large.

In other words, for example, the instability of focusing and tracking servos immediately after a seek operation, the influence of electrical disturbance noise on the detection system, the influence of dust in the air on the optical system, the influence of defects in optical disk media, and the influence of attached dust, etc. 8M2, AM4, 7 that provides an opportunity to read the address
, 10 detection errors are likely to occur.

Furthermore, even if 8M2 or AM4, 7, or 10 is found, the address itself may be misread, and the address error detection CRCC will immediately determine it as an address error. In response to an error, the optical disc device will repeatedly read the address by retrying. Even if the data can be read out correctly in the end, an increase in response time due to waiting for rotation is unavoidable.

Furthermore, in the worst case, the address cannot be read and data cannot be recorded or reproduced. In this case, there is a slight possibility that the recording operation can be rescued by so-called replacement processing, but in the reproduction operation, data may be lost, causing a great loss to the user.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to provide an address detection method for an optical disk storage device that improves data reliability and prevents sector addresses from being overlooked.

Means for Solving the Problems> The present invention, which achieves the above-mentioned objects, includes several beam irradiation means that are arranged in order along the rotational direction of an optical disk and can operate independently, and a A recording/reproducing operation sequence is performed using an address detecting means provided corresponding to the reflected light of the address detecting means, a means for determining whether the address is correct or incorrect by the address detecting means, and at least one address determined to be correct by the determining means. and a means for performing address detection based on a plurality of beam irradiation means in the direction along the rotational direction of the optical disk, for example, each beam irradiation means for erasing, recording, and reproducing. If the address is correctly detected by at least one of the beams, the operation sequence is continued.

This means that when correctly detecting an address, the SMSA provides an opportunity to read the address rather than the address itself.
This shows that M's mistake is more of a problem and cannot be ignored.

Note that the conventional beam irradiation means for address detection uses, for example, only the reproduction beam irradiation means, and for example, when using each beam irradiation means for reproduction, recording, and erasure, only on-tracking is used. It is used only for tracking servo.

Embodiments The present invention will now be described in detail with reference to FIGS. 1 and 2. FIG. 2 is a diagram illustrating the configuration of an optical head of a magneto-optical disk device that realizes erasing, recording, and reproducing operations in one rotation, and is arranged horizontally along the rotational direction of an optical disk medium. The second section provides an overview of erasing, recording, and reproducing operations using an optical head.
To briefly explain with reference to 21 in Fig. 2,
2 is a laser light source for erasing, 22 is a laser light source for recording, 23 is a laser light source for reproduction, 24 is an erasing beam, 25 is a recording beam, 26 is a reproduction beam, 29 is a positive mark, 30 is a positive drive mechanism, 31 is a magneto-optical disk medium that rotates in the direction of the arrow, and 32 and 33 are recording domains. First, in the erasing operation, the erasing beam 24 emitted from the erasing laser beam t121 hits the optical system in the positive ring 29. The light passes through and is irradiated onto a predetermined track on the magneto-optical disk medium 31. The recording domain 82 is erased by continuous irradiation with the erase beam 24. Following this, a recording operation is performed within the same rotation. A recording beam 2 is intermittently emitted from a recording laser light source 22 according to recording data.

The recording beam 2 is irradiated onto the magneto-optical disk medium 31 while being controlled by an appropriate mirror or the like so that its condensing position on the surface of the magneto-optical disk medium 31 coincides with the condensing position of the reproduction beam 26. By irradiating this recording beam 25, a new recording domain 33 is formed.

Further, a reproducing operation is performed successively to the above-described erasing/recording operation. The reproduction beam 26 emitted from the reproduction laser beam 1g 123 passes through the optical system in the positive position 29,
The light is irradiated onto the magneto-optical disk medium 31. By irradiating this reproducing beam 26, the recording domain 33 recorded immediately before is read out. In this way, continuous operations of erasing, recording, and reproducing can be performed within one rotation.

FIG. 1 is a detailed explanation of the present invention, and shows a light beam that completes erasing, recording, and reproducing within one rotation of the disk using the three beams for erasing, recording, and reproducing arranged along the rotational direction mentioned above. 1 is a configuration diagram of an optical disk storage device incorporating a head 51. FIG. In FIG. 1, 50 is the same magneto-optical disk medium as 31 in FIG. 2, 51 is an optical head, and 52 is a magneto-optical reproduction signal detector.

53 is an erase beam reflected light amount detector, 54 is a recording beam reflected light amount detector, 56 is a reproduction circuit, 57 is a servo circuit, 60 is an address detection circuit using the erase beam reflected light, 6
Reference numeral 1 denotes an address detection circuit using reflected light from the recording beam, and 62 an address detection circuit using reflected light from the reproduction beam.

65 is a control device.

As described above, the optical head 51 detects the intensity of reflected light from the magneto-optical disk medium 50 of three beams for erasing, recording, and reproducing within one rotation of the disk.
4.55. Of course, focusing and tracking error signals are also detected by means known from the reflected light amount detection@53, 5a, 55.

The outputs of the reflected light detection l#s 53, 54, and 515 are input to address detection circuits 60, 61, and 62, respectively. here,
As explained using FIG. 2, the address is read after 8M detection and AM detection are performed. The address detection circuits 60, 61 and 62 also check whether or not there is an error in this reproduced address. The outputs of the address detection circuits 60, 61, and 62 to the control device 65 are the read address and its correctness determination information.

Further, the outputs of the reflected light amount detectors 53, 54, and 55 are also input to the servo circuit @57. These are treated as focusing and tracking error signals, and the optical head 51
is fed back to the focusing and tracking drive system.

Furthermore, the output of the magneto-optical reproduction signal detection @52 is the output of the reproduction circuit 5.
6 is input. In the reproduction circuit 56, amplification, equalization,
After being detected and binarized, it is demodulated and sent to the control device 6.
5 will be informed.

The control device 65 exchanges command signals and recording/reproduction data with the host device, and operates the optical head 51 according to the command signals.

Furthermore, if there is at least one correct address among the read addresses and correct/incorrect judgment information obtained from the address detection circuits 60, 61, and 62, the address is erased using the address.

Controls execution of recording and playback operation sequences.

For example, when performing only a reproduction operation, if an address is correctly obtained from the erasing beam, but an address is not correctly obtained from the subsequent recording beam and reproduction beam, the address from the erasing beam, that is, the address by the erasing beam reflected light. The address output from the detection circuit 60 is used. Although the address detection is performed based on the erase beam reflected light, the data reproducing operation itself is detected using the reproducing beam, and of course, the so-called sync pattern indicating the beginning of recorded data is detected using the reproducing beam.

In address detection, the probability of address detection can be improved by differentiating the detection thresholds of the three address detection circuits for erasure, recording, and reproduction.

<Effects of the Invention> As explained above, according to the present invention, the rate of missed sector addresses on optical disk media is r! ! Since the number is reduced by 1, there is an advantage that the reliability of the recording/reproducing operation is greatly improved. It also has the advantage that the probability of executing a retry operation due to a missed sector address is reduced, and device performance such as response speed can be maintained. Further, as the optical disk medium deteriorates over time, the address portion is also affected by defects, etc., but the present invention improves the address detection rate, and has the advantage that the life of the medium can be equivalently improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an optical disk storage device according to an embodiment of the present invention, FIG. 2 is a basic block diagram of an optical head, and FIG. 3 is an explanatory diagram illustrating an address format. In the figure, 21 is an erasing laser light source, 22 is a recording laser light source, 23 is a reproduction laser light source, 24 is an erasing beam, and 25
is a recording beam, 26 is a reproduction beam, 29 is a positive beam,
Reference numeral 30 denotes a drive mechanism for straightening, 31 a magneto-optical disk medium, 32, 33 a recording domain, 50 a magneto-optical disk medium, 51 an optical head, 52 a magneto-optical reproduction signal detection magazine, 5
3 is an erase beam reflected light amount detector, 54 is a recording beam reflected light amount detector-155 is a reproduction beam reflected light amount detector,
56 is a reproducing circuit, 57 is a blank circuit, 60 is an address detection circuit using reflected erase beam, 61 is an address detection circuit using reflected recording beam, 62 is an address detection circuit using reflected reproduction beam, and 65 is a control device. be.

Claims (1)

[Scope of Claims] A plurality of beam irradiation means that are arranged in order along the rotational direction of an optical disk and can operate independently; and an address detection means that is provided corresponding to the light reflected by each beam from the beam irradiation means. , means for determining whether an address is correct or incorrect by this address detecting means, and means for executing a recording/reproducing operation sequence using at least one address determined to be correct by this determining means. method.