JP2696895B2 - Optical disk control information recording method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for recording control information on an optical disk.

2. Description of the Related Art Conventionally, control information of an optical disk includes recording / reproducing laser power, data modulation method, error correction method, number of sectors and size of an optical disk for achieving recording / reproducing compatibility with various optical disks with one drive device. Recorded, for example, Information Processing Society of Japan Information Standards Committee SC23
As proposed in the control track ad hoc material (10-4), a recording method using pits is known.

FIG. 4 shows the format of a control track of this conventional example. As shown in FIG.
Data is repeatedly recorded on the track three times as control information. Each data consists of 128-bit data, an 8-bit error detection code CRC at a 24-bit address, a preamble PR for clock recovery, and a synchronous SYN indicating the beginning of the data as shown in FIG. 4 (b). Is done. Each data bit is recorded over several hundred tracks by phase encoding (PE) modulation shown in FIG. 4C at a frequency low enough to be read at various rotation speeds.

That is, when the optical disk is inserted into the drive device, the drive device does not know whether the recording is land recording or groove recording of the guide track of the disk, so the optical head is moved by the linear motor to read the control track part, and this is read. The control information is read, the disc-specific information such as the correct tracking polarity, recording method, recording / reproducing condition, recording area, etc. is known, and the operation mode of the drive device is set. By doing so, various types of optical discs can be
It can be used with one drive device.

Problems to be Solved by the Invention However, in the above configuration, the control track cannot be sought directly because the address of the optical disc cannot be read at first. Read one. This necessitates a precise mechanism for accurately capturing the control track by the coarse search without reading the track address in the drive device.
As a result, when the disk is exchanged by the drive device, it takes time to read the control information from the control track, and there is a problem that the drive device starts up slowly. In addition, there is a problem that tracking cannot be properly performed because the tracking polarity is unknown, and the reliability of data reading is low.

In view of the foregoing, an object of the present invention is to provide a method for recording control information on an optical disc that detects control information of various optical discs quickly and with high reliability.

Means for Solving the Problems A control track of an optical disc according to the present invention is composed of a plurality of sectors including a sector identifier section recording address information and a control field section recording control information, and the control field section is composed of a sector identifier section. In the same format as above, the control information is divided into recordable information units in the control field portion, and the information unit is recorded in each sector of one track, and the information unit is simultaneously updated by updating the track address of the control track. This is a control information recording method for an optical disk in which control information is recorded in pits on a plurality of tracks.

According to the present invention, the address information is read from the sector identifier section of the track of the optical disk to search for the first control track, the information unit is read from the control field section of one sector of the control track, and the reading is completed. Then, the next track is searched and the control track is read out similarly. The above operation is performed up to the last control track, and the control information is reproduced by arranging the information units read from the control field section of each track in the order of the track address.

Embodiment FIG. 1 is a sector layout diagram of control tracks formed as pits on a disk substrate of an optical disk prepared by the method of the present invention. The control track is composed of m tracks, and each track has n sectors. Each sector has a sector identifier ID recording the sector address and a control field CF recorded in an area corresponding to the data field of the data recording sector.
1, CF2, CF3, ..., CFm. Here, the control field portion has the same format as the sector identifier portion ID, and records a control information unit divided into byte units of the address of the sector identifier portion. As shown in FIG. 1, the control information includes a control field portion CF1, a track 2
, The same control information unit is recorded in each sector in one track such as the control field section CF2,.
While the control information unit is updated with the track address, all the control information is recorded on the track m. That is, the control information is recorded in the sector in a form divided into control information units for each control track. The control information includes, in order from the head control track, the control field portion of any one of the sectors 1,..., N in CF1, CF2, CF3,.
…, Can be read by reading CFm. The control track is read out by a procedure such as a search for a head control track, a control field portion from a sector, and a search for an adjacent track. By reading the control field section, the next track can be immediately accessed. Therefore, it is possible to read the control information one after another without waiting for the rotation of the optical disk.

FIG. 2 is a configuration diagram of a format of a control track of an optical disk created by the method of the present invention. The control track shown in FIG. 2A is composed of a sector identifier ID and a control field CF recording control information CD, and each of the sectors S0, S1 to Sn has a double-written control field CF.
As shown in FIG. 2 (b), the sector identifier part ID is composed of doubly recorded addresses A0 and A1, and each address is an address identification flag provided at the most significant bit of the higher track address TH of the track address TA. It is distinguished by 0/1 of F1. Addresses A0 and A1 are preamble PR for clock recovery, address mark AM indicating the beginning of data,
Error detection code CR such as address information TH, TL and cyclic code
C and a postamble P0 for clock recovery.

The address information is a high-order track address TH, a low-order track address TL, and a sector address SA. The sector address SA is composed of sector address data SD and a CD / ID identification flag F2. F2 is set to, for example, "0".

FIG. 2C shows the format of the control field section CF. The basic structure is the same as the sector identifier ID, and the address information corresponds to the control information. That is, TA corresponds to bytes B0 and B1, and SD of SA corresponds to data byte B2. The CD / ID identification flag F2 is set to "1" opposite to the sector identifier ID in the control track, and is distinguished from the sector identifier ID.

If frequency modulation (FM) where input data bits always include clock bits or PE (Phase Encode) modulation is used as the modulation method for the sector identifier ID, playback can be performed without using a PLL or the like for clock recovery for signal demodulation. (2,7) Run Length Limited Code (RLLC: RunLength)
Data recording density is 1/3 compared to Limited Code) modulation
Therefore, since the bit error rate is good and the detection window time is long, there is a feature that accurate reproduction can be performed over a wide data rate with a small-scale circuit.

FIG. 3 shows an optical disk 1 produced by the method of the present invention.
FIG. 4 is a block diagram of a drive device for reading address information of a sector identifier part ID and control information CD from the disk drive. The data recording / reproducing unit and the servo system are omitted. 1 is an optical disk, 2 is a motor, 3 is an optical head, 4 is a sector identifier section reproducing circuit, 5 and 6 are AND circuits, 7 is a seek circuit, and 8 is an inverter. In the figure, the drive device is a seek circuit 7
, The address information of the control track and the target track address signal 9 are added. The seek circuit 7 compares the address signal 10 read by the sector identifier section reproducing circuit 4 with the target track address signal 9 and seeks the optical head 3 to the target track at high speed. The reproduction signal 11 of the optical head 3 is demodulated by the sector identifier reproduction circuit 4 and outputs a demodulated signal 12. The demodulated signal 12 is one of the address information TA and SA and the control information CD, and is distinguished into the address signal 10 and the control information signal 14 by the AND circuits 5 and 6 by the identification flag F2 signal 13. That is, the identification flag F2 signal
If 13 is "1", the AND circuit 5 is enabled and the address signal 0
If it is “0”, it is inverted by the inverter 8 and the AND circuit 6 becomes effective, and the control information signal 14 is output.

If the sector identifier section ID has a clock such as PE modulation in each bit, the sector identifier section reproducing circuit 4 does not require a PLL circuit for clock reproduction, and can perform well even when the disk rotation speed changes over a wide range. Can be played.

As is apparent from the above description, the control track records the same data over one track, so that the reliability is extremely high. Since the control information is arranged in the track address order, the reading speed is high. There is a feature that does not depend.
In addition, even if the number of rotations of the optical disk changes, the track address information can be read accurately and the control track can be directly sought, so that the control information can be quickly detected from the control track, greatly reducing the startup time of the drive unit when replacing the disk. can do.

As described above, according to the present invention, the start-up time of a drive device at the time of disk replacement can be achieved by reliable reproduction of control information of a control track, independence from a sector format, and high-speed control track search. The practical effect is great, for example, can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is a diagram showing a sector arrangement of a control track of an optical disk prepared by the method of the present invention, FIG. 2 is a configuration diagram of an identification flag F2 and a track format, and FIG. ID
FIG. 4 is a block diagram of a drive unit for reading address information and control information CD. FIG. 4 is a configuration diagram of a conventional control track format. ID: Sector identifier, CF: Control field in which control information is recorded, A0, A1: Address, P
R: Preamble, AM: Address mark, CRC: Error detection code, PO: Postamble, TA: Track address, TH: Higher track address, TL: Lower track address, SA: Sector address, SD: Sector address data, F1: Address identification flag, F2:
CD / ID identification flag, B0, B1, B2 ... data bytes for storing control data, DF ... data field part
1 ... optical disk, 2 ... motor, 3 ... optical head, 4
…… Sector identifier playback circuit, 5,6… AND circuit, 7…
Seek circuit, 8 Inverter, 9 Target track address signal, 10 Address signal, 11 Reproduction signal, 12
... demodulated signal, 13 ... identification flag F2 signal, 14 ... control information signal.

 ──────────────────────────────────────────────────の Continuing from the front page (72) Inventor Joe Kuroki 1006 Kazuma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Inventor Yasu Higashiya 1006 Kazuma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-60-115069 (JP, A) JP-A-60-111372 (JP, A) JP-A-62-234274 (JP, A)

Claims (3)

(57) [Claims] 1. A control information recording method for an optical disc, comprising a sector for data recording, which comprises a sector identifier section and a data recording section, for recording data in the data recording section, and control tracks formed as pits on a disc base material. The control track is divided into sectors similarly to the data sector, and the sector has a sector identifier having the same format as the sector identifier of the data sector and a control having the same format as the format of the sector identifier. A field portion is provided, and a sector identifier portion and a control field portion of the control track are provided with a mutually identifiable flag, and control information is divided into a number of bytes corresponding to the control field portion and recorded in the control field portion. Control information recording method of an optical disc characterized by Rukoto. 2. The control information recording method for an optical disk according to claim 1, wherein the divided control information divided into the number of bytes is sequentially recorded in the same control track as the same control information in the order of addresses of adjacent tracks in each sector. . 3. The control information recording method for an optical disk according to claim 1, wherein the divided control information divided into the number of bytes is recorded in a control field portion of a sector of a control track in a sector order.