JPH0369068A - Multibeam recording and reproducing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a multi-beam recording and reproducing apparatus that simultaneously records and reproduces information on a plurality of tracks of an optical recording medium.

(Prior Art) Conventionally, in an optical disk recording/reproducing device, in order to improve the transfer speed, a multi-beam optical head equipped with a laser diode array and a photodetector array is used to simultaneously record information on multiple tracks. or playback is occurring. That is, n laser diodes are simultaneously driven to collectively record or reproduce information on n tracks on the optical disk medium. As a result, at the same rotational speed of the optical disc medium, it is possible to obtain a data transfer rate that is 0 times the data transfer rate in an optical disc recording/reproducing apparatus using an optical head consisting of one laser diode.

Therefore, the time required for recording and reproducing information can be reduced to 1/n.

(Problem to be Solved by the Invention) However, as described above, when recording or reproducing information on multiple tracks at the same time, there are problems such as failures and failures of individual laser diodes constituting the laser diode array. This is a failure of the individual photoelectric conversion elements that make up the photodetector array. In other words, since a series of meaningful information is recorded or reproduced using n laser diodes and n photoelectric conversion elements, even if one laser diode or one photoelectric conversion element fails,
This is a fatal failure for the main device. Moreover, it is a permanent failure, and the laser diode array or photodata array must be replaced.

Particularly, if such a situation occurs in an optical disk recording/reproducing device incorporated in a large-scale computer system, it will cause a long system downtime, causing damage to many users.

Although the above event was a fixed failure of the laser diode array or photodetector array, intermittent failure conditions may also occur. In other words, one of the laser diodes in the laser diode array or one of the photoelectric conversion elements in the photodetector array may temporarily go into a defective state, and as a result, recording and reproducing quality may deteriorate and errors may occur. be. In principle,
Errors caused by this type of optical head tend to be extremely long burst errors, unlike errors caused by medium defects. Therefore, errors occur that cannot be compensated for by conventional error correction detection codes for relieving media defects, resulting in a problem in that the data reliability of the optical disk recording and reproducing apparatus is significantly reduced.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a multi-beam recording and reproducing device that increases data transfer speed and records and reproduces information on an optical recording medium with high data reliability. be.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a method for simultaneously recording information on a plurality of tracks on the optical recording medium using a multi-beam optical head. In a multi-beam recording and reproducing apparatus that performs reproduction, a first encoding circuit that creates a first error correction detection code formed in the longitudinal direction of the track of the optical recording medium based on recording target information;
a second encoding circuit that creates a second error correction detection code formed in a direction perpendicular to the tracks of the optical recording medium based on the recording target information; and a second encoding circuit that includes the multi-beam optical head; information recording means for recording the first and second error correction detection codes created by a second encoding circuit on the optical recording medium; and the first error correction detection code recorded on the optical recording medium. a first decoding means that decodes the first error correction detection code and generates error information of the first error correction detection code; a first decoding means that decodes the second error correction detection code recorded on the optical recording medium; a second decoding means for generating error information of the second error correction detection code;
A multi-beam recording and reproducing apparatus is proposed, which includes information reproducing means for generating reproduction information based on the decoding results and error information of the first and second decoding means.

Further, in claim (2), in the multi-beam recording/reproducing apparatus according to claim (1), the second
a first decoding means inputting error information of the error correction detection code and decoding the first error correction detection code based on the error information; Input the error information of the detection code, and based on the error information,
A multi-beam recording and reproducing apparatus is proposed, which is provided with a second decoding means for decoding the first error correction detection code.

Furthermore, in claim (3), in the multi-beam recording and reproducing apparatus according to claim (1) or (2), error information is input from the second decoding means, and based on the error information, the optical recording medium is We propose a multi-beam recording and reproducing device equipped with a failure detection circuit that generates a warning signal when it detects that errors occur continuously at a specific position.

(Function) According to claim (1) of the present invention, the first encoding circuit creates the first error correction detection code formed in the longitudinal direction of the track of the optical recording medium, and the second encoding circuit creates the first error correction detection code formed in the longitudinal direction of the track of the optical recording medium. A second error correction detection code configured in a direction perpendicular to the track of the optical recording medium is created by the circuit. The first and second error correction detection codes are simultaneously recorded on a plurality of corresponding tracks of the optical recording medium by an information recording means.

Further, when reproducing information recorded on the optical recording medium, the first and second error correction detection codes recorded on a plurality of tracks of the optical recording medium are converted into electrical signals by a multi-beam optical head. converted. Based on this electrical signal, the first error correction detection code is decoded by the first decoding means, and the second error correction detection code is decoded by the second decoding means.

Further, error information of the first and second error correction detection codes is generated by the first and second decoding means, respectively. Based on the decoding results and error information of the first and second decoding means, the information reproducing means generates reproduction information.

According to claim (2), the first error correction detection code is decoded by the first decoding means based on error information input from the second decoding means. Further, the second error correction detection code is decoded by the second decoding means based on error information input from the first decoding means.

Furthermore, according to claim (3), the failure detection circuit
Based on the error information input from the second decoding means, if an error occurs continuously at a specific position on the optical recording medium, this is detected and a warning signal is generated.

(Embodiment) FIGS. 1 and 2 illustrate a first embodiment in which the present invention is applied to a magneto-optical disk device. FIG. 1 is a block diagram showing the configuration, and FIG. 2 is a medium recording FIG. 3 is a diagram showing a format. In the figure, 1 is a magneto-optical disk medium, 2 is a multi-beam optical head, a laser diode array 3,
It is composed of a polarizing beam splitter 4, an objective lens 5, a lens 6, and a photodetector array 7.

The laser diode array 3 consists of ten laser diodes, which are arranged in parallel so as to correspond to ten adjacent tracks of the magneto-optical disk medium 1, and are operated individually.

The polarizing beam splitter 4 is a laser diode array 3
The laser light emitted from each laser diode is transmitted and enters the objective lens 5.

The objective lens 5 causes each of the laser beams emitted from each laser diode of the laser diode array 3 to be incident on ten adjacent tracks of the magneto-optical disk medium 1 . Further, the laser beams reflected from each of these tracks are incident on the polarizing beam splitter 4.

The lens 6 enters the polarizing beam splitter 4 from the objective lens 5 side, and makes the laser light reflected by the polarizing beam splitter 4 enter the photodetector array 7 .

The photodetector array 7 consists of an analyzer and ten photoelectric conversion elements, and these photoelectric conversion elements are arranged in parallel so as to correspond to the tracks of the magneto-optical disk medium 1 corresponding to each laser diode of the laser diode array 3. Laser light reflected from these tracks is made incident on each of the corresponding photoelectric conversion elements through a lens 6.

8 is an electromagnet, which is magnetized based on a signal from a recording circuit 12, which will be described later.

10 is a first encoding circuit which inputs recording target information W;
Based on this recording target information W, the magneto-optical disk medium 1
A first error correction detection code Cm formed in the longitudinal direction of the track is created.

11 is a second encoding circuit which inputs the recording target information W;
Based on this recording target information W, the magneto-optical disk medium 1
A second error correction detection code ch formed in the direction perpendicular to the track is created.

12 is a recording circuit, and first and second encoding circuits 10.1
1 to the first and second error correction detection codes Cm and Ch, the laser diode array 3 and the electromagnet 8 are driven based on these, and the first and second error correction detection codes Cm and Ch are input.
m, Ch are simultaneously stored on ten tracks of the magneto-optical disk medium 1.

Reference numeral 13 denotes a reproducing circuit which inputs electrical signals corresponding to 10 tracks of the magneto-optical disk from the photodetector array 7, binarizes the electrical signals, and outputs a synchronized and demodulated demodulated signal.

14 is a first decoding circuit which inputs the demodulated signal from the reproducing circuit 13, decodes the first error correction detection code Cm of the demodulated signal, and outputs reproduced data. At this time, if an error is detected in the first error correction detection code Cm, the position and size of the error are determined based on a predetermined correction algorithm, the error is corrected, and then the reproduced data is output. .

Further, when an error is detected, an error detection signal indicating that an error has been detected and a correction possibility signal indicating whether or not the error can be corrected are output.

A second decoding circuit 15 inputs the demodulated signal from the reproducing circuit 13, decodes the second error correction detection code ch of the demodulated signal, and outputs reproduced data. At this time, if an error is detected in the second error correction detection code ch, the position and size of the error are determined based on a predetermined correction algorithm, the error is corrected, and then the reproduced data is output. .

Further, when an error is detected, an error detection signal indicating that an error has been detected and a correction possibility signal indicating whether or not the error can be corrected are output.

16 is a data selection circuit, and the first and second decoding circuits 1
Reproduction data, an error detection signal, and a correction possibility signal are input from each of 4.15, and error-free reproduction data is output as reproduction information R. That is, if no error is detected in each of the first and second decoding circuits 14.15, the reproduced data output from each of the first and second decoding circuits 14.15 is the same. becomes. Furthermore, if an error is detected in both the first and second decoding circuits 14 and 15, the reproduced data in which the error has been corrected is selected, and this reproduced data is output as reproduced information R.

In addition, other components necessary for magneto-optical disk devices such as actuator system, positioner system, focus system, etc.
The track servo system, command processing system, etc. are already known.
Since it is not directly related to the present invention, the explanation will be omitted.

The information recording means includes a multi-beam optical head and an electromagnet 8.
and a recording circuit 12, and the first decoding means is composed of a reproduction circuit 13 and a first decoding circuit 14. Further, the second decoding means is composed of a reproduction circuit 13 and a second decoding circuit 15, and the information reproduction means is composed of a data selection selection circuit 16.

Furthermore, in this embodiment, the first error correction detection code Cm
consists of a 104-byte information byte DATA and a 16-byte check byte CHK-m, and has a code length of 120 bytes L.
It has a code that can correct up to 8 error bytes.

Further, the second error correction detection code ch has a code length of 10 bytes, a check byte CHK-h of 2 bytes, and a maximum of 1
It is set to a code that can correct error bytes up to the byte. These first and second error correction detection codes Cm
, Ch are simultaneously recorded on ten adjacent tracks #O to #9 of the magneto-optical disk medium 1 in the format shown in FIG. That is, the first error correction detection code Cm is recorded on each of the eight tracks from track non-0 to track #7. Also, the second error correction detection code ch is recorded across tracks #0 to #9, and check bytes CHK are recorded on tracks #8 and #9.
-h only is recorded.

Next, the operation of the first embodiment having the above-described configuration will be explained.

Recording target information W sent from a main device (not shown) is distributed to first and second encoding circuits via a buffer circuit (not shown). At this time, the recording target information W is distributed such that each of the first and second error correction detection codes Cm and Ch is easily configured in the format shown in FIG.

That is, the first encoding circuit 10 includes the magneto-optical disk medium 1.
Data to be recorded in the longitudinal direction of the track is sequentially input to the second encoding circuit 11, and data to be recorded in the direction perpendicular to the track is sequentially input to the second encoding circuit 11. As a result, the first encoding circuit 10 outputs the check byte CHK-m of the first error correction detection code Cm, and the second encoding circuit 11 outputs the check byte CHK-h of the second error correction detection code ch. generated respectively.

Thereafter, the recording circuit 12 records the information byte D based on the first and second error correction detection codes Cm and Ch.
Modulation processing is performed according to the data of the ATA and two types of inspection bytes CHK-m and CHK-h, and each laser diode of the laser diode array 3 of the multi-beam optical head 2 is driven, and each laser diode is emits light.

Further, the electromagnet 8 is driven.

Laser light emitted from each laser diode of the laser diode array 3 passes through the polarizing beam splitter 4 and is focused onto the magneto-optical disk medium 1 by the objective lens 5. At this time, each laser beam corresponds to ten adjacent tracks on the magneto-optical disk medium 1. As a result,
According to the polarity of the electromagnet 8, ten tracks corresponding to the laser beam on the magneto-optical disk medium 1 are magnetized, and information bytes DATA, test bytes CHK-m and CHK-ri are recorded.

On the other hand, when reproducing recorded information, the optical path of the laser beam reflected by the ten tracks on the magneto-optical disk medium 1 is bent at right angles by the polarizing beam splitter 4 and is incident on the lens 6.

Furthermore, the ten laser beams are separated by the lens 6 and are respectively incident on the corresponding photoelectric conversion elements of the photodetector array 7. After the optical signal is converted into an electric signal by these photoelectric conversion elements, it is demodulated by the reproduction circuit 13 and a demodulated signal is output. This demodulated signal is input to the first and second decoding circuits 14.15, and the first
In the decoding circuit 14, the first error correction detection code Cm is
In the second decoding circuit 15, the second error correction detection code ch
are respectively decoded, and reproduced data, an error detection signal, and a correctability signal are output as described above. 1st and 2nd
Based on these data and signals output from the decoding circuits 14 and 15, the data selection circuit 13 outputs reproduction information R to the main device as described above.

Next, a second embodiment of the present invention will be described.

FIG. 3 is a block diagram showing the configuration of the second embodiment.
Similarly to the embodiment, the present invention is applied to a magneto-optical disk device. In the figures, the same components as those in the first embodiment are represented by the same reference numerals, and the explanation thereof will be omitted. Also,
As with the first embodiment, explanations of constituent parts that are not directly related to the present invention will be omitted.

The difference between the second embodiment and the first embodiment described above is that the first and second decoding circuits 14 and 15 in the first embodiment are replaced with the first decoding circuits 14 and 15, respectively. and second decoding circuits 34 and 35 are provided.

That is, the first decoding circuit 34 inputs the demodulated signal from the reproducing circuit 13, decodes the first error correction detection code Cm of the demodulated signal, and outputs reproduced data. At this time, the first
When an error is detected in the error correction detection code Cm, the position and size of the error are determined based on a predetermined algorithm, the error is corrected, and then reproduced data is output. Further, when an error is detected in the first error correction detection code Cm, the position information 30 of this error is transferred to the second decoding circuit 35.
Output to. Further, error position information 31, which will be described later, is input from the second decoding circuit 35, and the error correction process described above is performed using this as a pointer.

The second decoding circuit 35 inputs the demodulated signal from the reproducing circuit 13, and converts the second error correction detection code ch of this demodulated signal.
decodes and outputs playback data.

At this time, if an error is detected in the second error correction detection code ch, the error position and size are determined based on a predetermined algorithm using the error position information 30 input from the first encoding circuit 34 as a pointer. After determining and correcting errors,
Output playback data.

Further, error location information 31 indicating the location of the error is output to the first decoding circuit 34.

Further, when an error is detected, each of the first and second decoding circuits 34 and 35 sends an error detection signal indicating that an error has been detected, and a correction possibility signal indicating whether or not the error has been corrected. Output.

According to the second embodiment having the above-described configuration, the first and second decoding circuits 34 and 35 mutually perform error correction processing using the error position information 30 and 31 inputted from the other decoding circuit as pointers. Therefore, the rate at which errors can be corrected increases compared to the first embodiment described above, and higher quality reproduction information R can be obtained.

Next, a third embodiment of the present invention will be described.

FIG. 4 is a block diagram showing the configuration of the third embodiment.
Similarly to the second embodiment, the present invention is applied to a magneto-optical disk device. In the figures, the same components as those in the first or second embodiment are represented by the same reference numerals, and the description thereof will be omitted. Furthermore, descriptions of constituent parts that are not directly related to the present invention will be omitted.

Further, the difference between the third embodiment and the second embodiment described above is that a failure detection circuit 40 is provided.

When the failure detection circuit 40 receives the above-mentioned error detection signal from the second decoding circuit 35 and detects that an error occurs continuously at a specific position or a specific track of the magneto-optical disk medium 1, Then, a warning signal 42 is output to the main device. That is, the error detection signal includes information indicating the number of correctable errors, the position of the errors, the existence of errors exceeding the correction ability, etc. The failure detection circuit 40 records the number and location of errors based on the error detection signal, and generates a warning signal 42 when it detects that errors occur continuously at a specific location. As a result, a warning is issued to the main device, and measures such as a warning to the user are taken. Therefore, failures in the magneto-optical disk medium 1, the laser diode array 3 of the multi-beam optical head 2, the photodetector array 7, etc. can be discovered at an early stage.

Incidentally, the present invention relates to an error correction detection code Cm formed in the longitudinal direction of the track and the direction perpendicular to the track.

It can be applied regardless of the type of channel, configuration, data arrangement method, etc.

Furthermore, the present invention is applicable regardless of the configuration of the optical system of the multi-beam optical head, the number of laser diodes in the laser diode array, the physical arrangement, structure, material, etc. of the laser diodes.

Further, the present invention is applicable to all optical recording and reproducing devices such as various optical disks including magneto-optical disks, optical tapes, and optical cards.

(Effects of the Invention) As explained above, according to claims (1) to (3) of the present invention, not only can errors in reproduced data due to defects in the optical recording medium be corrected, but also the laser constituting the optical head can be corrected. Data errors caused by intermittent and fixed failures in diode arrays and photodetector arrays can be detected and corrected, greatly improving the data reliability of optical recording and reproducing devices using multi-beam optical heads. I can do it. As a result, in a large-scale computer system using the optical recording/reproducing device, it is possible to prevent a long system down due to a data error in the optical recording/reproducing device, and it is extremely important that no damage is caused to the user. Demonstrates excellent effects.

Further, according to claim (2), in addition to the above effects, the first
Error information is exchanged between the second decoding means and the second decoding means, and data errors are corrected based on this error information, so that the rate at which errors can be corrected increases. Thereby, the reliability of data can be further improved and high quality reproduction information can be obtained.

Furthermore, according to claim (3), in addition to the above-mentioned effects, if an error occurs continuously at a specific position on the optical recording medium, this is detected by the failure detection circuit and a warning signal is generated. This method has the advantage that failures in the optical recording medium, the laser diode array of the multi-beam optical head, the photodetector array, etc. can be discovered at an early stage.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of the first embodiment of the present invention, FIG. 2 is a diagram showing the medium recording format, and FIG. 3 is a block diagram showing the configuration of the second embodiment of the present invention. FIG. 4 is a block diagram showing the configuration of a third embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Magneto-optical disk medium, 2... Multi-beam optical head, 3... Laser diode array, 4... Polarizing beam splitter, 5... Objective lens, 6... Lens, 7... - Photodetector array, 8... Electromagnet, 10... First encoding circuit, 11... Second encoding circuit, 12... Recording circuit, 13... Reproducing circuit,
14.34...first decoding circuit, 15.35...
Second decoding circuit, 16... data selection circuit, 40...
...Failure detection circuit.

Claims (3)

[Claims] (1) In a multi-beam recording and reproducing device that simultaneously records and reproduces information on a plurality of tracks on an optical recording medium using a multi-beam optical head, based on the information to be recorded, a first encoding circuit that creates a first error correction detection code formed in a direction perpendicular to the track of the optical recording medium based on the recording target information; the first and second error correction detection codes created by the first and second encoding circuits are recorded on the optical recording medium; information recording means for decoding the first error correction detection code recorded on the optical recording medium and generating error information of the first error correction detection code; a second decoding means that decodes the second error correction detection code recorded on an optical recording medium and generates error information of the second error correction detection code; and the first and second decoding means. 1. A multi-beam recording and reproducing apparatus comprising: information reproducing means for generating reproduction information based on the decoding result of the decoding means and error information. (2) a first decoding means that inputs error information of the second error correction detection code from the second decoding means and decodes the first error correction detection code based on the error information; and a second decoding means for inputting error information of the first error correction detection code from the first decoding means and decoding the first error correction detection code based on the error information. (1) The multi-beam recording/reproduction device described. (3) A failure that generates a warning signal when error information is input from the second decoding means and it is detected that errors occur continuously at a specific position on the optical recording medium based on the error information. The multi-beam recording and reproducing apparatus according to claim 1 or 2, further comprising a detection circuit.