JPH09270172A - Direct read after write type optical disk device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the reliability of written data by writing the same data in plural sessions at the time of recording. SOLUTION: After the data inputted from an external interface 5 are stored in a memory 6, the data pass a signal processing part 4 and a pickup 2 and they are made to be recorded on the direct read after write type disk 1 of CD-R or the like or the data recorded on the disk are made to be reproduced. The pickup 2 is applied with various kinds of servos by a servo means 3. The CD-R disk 1 is consisting of two sessions, and at the time of recording data are written by the number of determined sectors from the starting position of a first session and thereafter, data are written by the number of the same sectors from the starting position of a second session. Then, data of the same contents are written in program areas of the two sessions by repeating this.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a write-once type optical disc device in which recorded data is highly reliable.

[0002]

2. Description of the Related Art Recently, as a write-once optical disc, a CD-
R disk is used. Such CD-R discs are in relatively small lots (eg less than about 50 discs)
It is effective for the production of CDs and the like, and is used for recording image data, music data, computer information and the like. CD-R discs are write once (Wri
Since it is te once), the sector once written cannot be overwritten. For example, when recording a certain track by the track burst writing method, if an error occurs for some reason and recording of information fails,
The track can no longer be added or played. For example, this corresponds to the case where there is dust or scratches on the disc during recording.

[0003]

However, how to deal with dust and scratches on the write-once type optical disc during recording on the write-once type optical disc is an important issue related to data reliability. However, as a countermeasure, only the measures such as disk cleaning, servo gain down, and warning at the end of writing are taken, and there is a problem that the reliability of the device is not guaranteed at all. .

The present invention has been made to solve the above problems, and an object of the present invention is to provide a write-once optical disc in which written data is highly reliable.

[0005]

According to the present invention, in order to achieve the above-mentioned object, in a write-once optical disc apparatus for irradiating a write-once optical disc with a semiconductor laser to record information, a plurality of sessions are recorded in the same session. It is a write-once type optical disk device, which is characterized by writing the above data. Further, it is characterized in that uncompressed data is recorded in the first session and compressed data is recorded in the second session and thereafter. In a write-once optical disc apparatus that irradiates a write-once optical disc with a semiconductor laser to record information, when recording data for n tracks of 1/2 or less of the write-once optical disc capacity, from 1 to n tracks and from n + 1 Two
The write-once optical disc device is characterized in that the same data is recorded up to n tracks and information from 1 to n tracks is recorded in the lead-in area. In addition, uncompressed data is recorded on tracks 1 to n, and n + 1 to 2n
The track is characterized by recording compressed data.

[0006]

According to the write-once optical disc apparatus of the present invention,
When data is recorded, the same data is recorded on a plurality of sessions or n + 1 to 2n tracks, and highly reliable data recording is performed. Further, the data is compressed and recorded in the second session and thereafter or in the tracks from n + 1 to 2n, and the writing time is shortened.

[0007]

The present invention will be specifically described below with reference to examples. As shown in FIG. 2, the write-once optical disc apparatus according to this embodiment includes a pickup 2 for recording data on a write-once optical disc 1 such as a CD-R, or for reproducing recorded data. Servo means 3 for applying various servos to the pickup 2, signal processing processing means 4 for detecting various signals from the pickup 2,
And an external interface 5 for exchanging data with the outside, and a memory 6 connected to the external interface 6.

Next, the operation of this embodiment will be described.
The data input from the external interface is the memory 6
After being stored in, the signal passes through the signal processing unit 4 and the pickup 2, and as shown in FIG. 1, first, the start position of the first session (00:00:00 sector: 00:00:00)
A certain number of sectors will be written. After that, from the start of the second session (in the example of FIG. 1, since the lead-in area of the second session is 1 minute, it becomes 31:00:00), the same number of sectors as described above is written. By repeating this operation, the data of the same content is recorded in the program area section of the first session and the second session of FIG. Such a disk configuration is a general C
Compatibility is assured by reading the first session for the D-ROM drive, and for the write / read of its own, by reading the same position in the second session when a read error occurs in the first session. , Compensation is possible, and the reliability of read data can be improved. A flow chart of this operation is shown in FIG.

Another embodiment will be described with reference to FIG. As shown in FIG. 3, the apparatus configuration of the present embodiment is a CD-
A pickup 2 for recording or reproducing information on a write-once disc 1 such as R, a servo means 3 for performing various servos on the pickup 2, a signal processing means 4 for detecting various signals from the pickup 2, and the outside. The compression circuit 7 is connected to the external interface 5 for exchanging signals, and the first memory 6 and the second memory 8 are connected to the external interface 5 and the compression circuit 7, respectively.

Next, the operation of this apparatus will be described with reference to FIG. The data input from the external interface is
The compression circuit 7 is stored in the first memory 6 and
The same data compressed by is stored in the second memory 8. Then, first, the data in the first memory 6 is written via the signal processing unit 5 and the pickup 2 from the start position of the first session (00:00:00 sector, 00:00:00 thereafter) for a predetermined number of sectors. After that, from the start of two sessions (in the example of FIG. 4, since the lead-in area of the second session is 1 minute, it becomes 41:00:00),
Write the data in the second memory. By repeating this operation, the same data content is obtained in the present embodiment, but the first session becomes the original data and the second session becomes the compressed data, so that the CD-RO can be read by the first session.
By maintaining compatibility with the M drive and recording compressed data from the second session onward, it is possible to effectively use the disk capacity and shorten the write time.

On the other hand, when reproducing this disc, first, the first session is read, and if there is no read error, the read operation is ended. If there is an error, the data at the same position in the next session is read. , This read data is expanded and the data is reproduced. Note that these operations are shown in the flowchart of FIG.

A third embodiment will be described. In the above example, in the case of multi-session, the lead-in area (LIA) and the lead-out area (LOA) of the second and subsequent sessions require a disk capacity of 1 minute and 30 seconds, respectively. Equivalent to. As the number of sessions increases, this invalid area increases by 15 Mbytes x (number of sessions-1). FIG. 5 shows an improvement of this. When writing n-track data having a disk capacity of 1/2 or less, the same data is written from 1 to n tracks and from n + 1 to 2n tracks, and 1 is written to LIA, that is, TOC. It is designed to write information from the first to nth tracks. That is, the 1st track and the n + 1th track, the 2nd track and the n + 2th track in FIG. 5 have the same data in the nth track and the 2nth track, and the TOC is information from the 1st to the nth track. In the case of self-writing / reading, the read error occurrence track + n due to TOC, PMA information, etc.
Data is compensated by reading tracks etc.,
Try to improve reliability.

Next, the operation will be described with reference to FIG.
In this embodiment, the data is not compressed. At the time of writing, first, the first and second tracks are sequentially written up to the nth track, and then the same data as the first track is referred to as the (n + 1) th track and the same data as the second track is referred to as the (n + 2) th track. As described above, the write operation is completed. On the other hand, in the read operation, first, reading is sequentially performed from the first session, and when a read error occurs in the mth track, the data of the (n + m) th track is read.

Next, the operation of the fourth embodiment will be described with reference to FIG. This embodiment is an example in which data is compressed and recorded on the (n + 1) th track and thereafter in the third embodiment as in the second embodiment. At the time of writing, first,
Write to the first and second tracks in sequence, then 1
Compress the same data as the track No. into n + 1 tracks,
The same data as the second track is compressed and sequentially written in the (n + 2) th track. On the other hand, when reading,
If the read error occurs after reading the mth track by reading sequentially from the first session, read the data of the (n + m) th track, extend the data, continue the read operation, and read when all the data is read. The operation ends.

[0015]

According to the present invention, since the same data is recorded in a plurality of sessions, the reliability of the data can be improved, and in the case of a CD-R disc, at least the first session is a general CD- It is possible to have compatibility such that the ROM drive can also read. In addition, by compressing and recording the data of the second session and thereafter, it is possible to effectively utilize the disk capacity and shorten the write time. Further, when writing n-track data that is ½ or less of the disk capacity, the data is written and information up to n-tracks is recorded in the TOC.
It has the compatibility of being readable by a D-ROM drive, and by compressing and recording the data of the (n + 1) th track and thereafter, the disk capacity can be effectively used and the write time can be shortened. Produce an effect.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a device according to a first embodiment of the present invention.

FIG. 3 is an explanatory view showing an apparatus according to a second embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a second embodiment of the present invention.

FIG. 5 is an explanatory diagram showing a third embodiment of the present invention.

FIG. 6 is a flowchart showing the operation of the first embodiment.

FIG. 7 is a flowchart showing the operation of the second embodiment.

FIG. 8 is a flowchart showing the operation of the third embodiment.

FIG. 9 is a flowchart showing the operation of the fourth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Write-once type optical disk 2 ... Pickup 3 ... Servo means 4 ... Signal processing means 5 ... External interface 6 ... Memory (first memory) 7 ... Compression circuit 8 ... Second memory

Claims (4)

[Claims] 1. A write-once optical disc device for irradiating a write-once optical disc with a semiconductor laser to record information, wherein the same data is written in a plurality of sessions during recording. 2. The write-once optical disc apparatus according to claim 1, wherein uncompressed data is recorded in the first session, and compressed data is recorded in the second session and thereafter. 3. In a write-once optical disc device for irradiating a write-once optical disc with a semiconductor laser to record information, in the case of recording data for n tracks of 1/2 or less of the capacity of the write-once optical disc, 1 to n tracks are recorded. Up to n +
A write-once optical disc device, wherein the same data is recorded on 1 to 2n tracks, and information on 1 to n tracks is recorded in the lead-in area. 4. The write-once optical disc apparatus according to claim 3, wherein uncompressed data is recorded on tracks 1 to n, and compressed data is recorded on tracks n + 1 to 2n.