# US 2002/0001263 A1 · Optical disk drive and method for processing data using the same

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2002/0001263 A1
- Document ID: US20020001263A1
- Status: Published application
- Kind: A1
- Application number: 09/894,305
- Filed: 2001-06-27
- Published: 2002-01-03
- Earliest claimed: 2000-06-30
- Assignees: Sony Corporation
- Inventors: Masayoshi Nagata
- Web page: https://patentgrep.com/patent/US20020001263A1

## CPC

- G11B 7/005: Reproducing (G11B7/0065 takes precedence)
- G11B 7/007: Arrangement of the information on the record carrier, e.g. form of tracks {, actual track shape, e.g. wobbled, or cross-section, e.g. v-shaped; Sequential information structures, e.g. sectoring or header formats within a track}
- G11B 11/10515: {Reproducing (compensating pit shift G11B11/1053)}
- G11B 11/10597: {Adaptations for transducing various formats on the same or different carriers}
- G11B 20/1217: {on discs}
- G11B 20/14: using self-clocking codes
- G11B: INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER (recording measured values in a way that does not require playback through a transducer G01D9/00; recording or playback apparatus using mechanically marked tape, e.g. punched paper tape, or using unit records, e.g. punched or magnetically marked cards G06K; transferring data from one type of record carrier to another G06K1/18; circuits for coupling output of reproducer to radio receiver H04B1/20; gramophone pick-ups or like acoustic electromechanical transducers or circuits therefor H04R)

## Abstract

According to the present invention, in a disk-shaped recording medium such as an optical disk and the like, a reference clock with a frequency corresponding to a reproduction frequency of data reproduced from a data recording region is divided in accordance with a ratio between a record density of a header region where pre-formatted data including a sector mark for indicating a leading position of a sector is recorded, and a recording density of a data recording region subsequent to the header region, so as to produce a sampling clock. Then, by use of thus-produced sampling clock, the sector mark is detected. This structure enables, even if the header region has a recording density different from the recording density of the data region, to use a sector mark detector having the same structure as of a sector mark detector which is employed in the case where the header region has the same recording density as that of the data region and therefore a reference clock is used. An optical disk drive with this structure can be produced at a low cost. In addition, the information about the ratio between the recording density of the header region and the recording density of the data recording region is obtained from the optical disk mounted to an optical disk drive, and the dividing ratio is automatically switched. With this structure, even if various kinds of optical disks having various ratio between the recording density of the header region and the recording density of the data recording region are mounted, it is possible to use sector mark detectors of the same structure and window generators of the same structure for these optical disks. The optical disk drive with this structure can be produced at a low cost. In addition, the user can omit the procedure of manually switching the dividing ratio.

## Claims

### Claim 1

An optical disk drive for handling an optical disk in which a sector as a recording unit is formed by a header region where pre-formatted data including a sector mark for indicating a leading position of a sector and a data recording region subsequent to the header region, and the header region has a recording density different from the recording density of the data recording region, comprising:
a data reproduction device for reproducing the pre-formatted data from the header region in the sector, and for reproducing data from the data recording region of the sector;
a clock generator for generating a reference clock with a frequency corresponding to a reproduction frequency of the data reproduced from the data recording region in the sector;
a divider for dividing the reference clock in accordance with the ratio between the recording density of the header region and the recording density of the data recording region, so as to generate a sampling clock with a frequency corresponding to the reproduction frequency of the pre-formatted data reproduced from the header region; and
a sector mark detector for detecting the sector mark from the pre-formatted data reproduced in the data reproducing device, by use of the sampling clock.

### Claim 2 (depends on 1)

An optical disk drive according to claim 1, wherein the optical disk has a recording region divided into plural zones in its radial direction, and
wherein the reference clock produced by the clock generator has a frequency different from zone to zone.

### Claim 3 (depends on 1)

An optical disk drive according to claim 1, wherein the pre-formatted data includes an address mark, and sector address information subsequent to the address mark, and
wherein the optical disk drive further comprises a window generator for generating a window signal for designating a range in which the address mark is to be detected from the pre-formatted data, by use of the sampling clock.

### Claim 4

An optical disk drive for handling an optical disk in which a sector as a recording unit is formed by a header region and a data recording region subsequent to the header region, comprising:
an information obtaining device for obtaining information about a ratio between the recording density of the header region and the recording density of the data recording density;
a data reproduction device for reproducing the pre-formatted data from the header region in the sector, and for reproducing data from the data recording region of the sector;
a clock generator for generating a reference clock with a frequency corresponding to a reproduction frequency of the data reproduced from the data recording region in the sector;
a divider for dividing the reference clock in accordance with the ratio between the recording density of the header region and the recording density of the data recording region, so as to generate a sampling clock with a frequency corresponding to the reproduction frequency of the pre-formatted data reproduced from the header region; and
a sector mark detector for detecting the sector mark from the pre-formatted data reproduced in the data reproducing device, by use of the sampling clock.

### Claim 5 (depends on 4)

An optical disk drive according to claim 4, wherein the optical disk has an information recording region in which information about the ratio between the recording density of the header region and the recording density of the data recording region, and
wherein the information obtaining device obtains the information about the ratio between the recording density of the header region and the recording density of the data recording region by reproducing this information from the information recording region.

### Claim 6 (depends on 4)

An optical disk drive according to claim 4, wherein the optical disk has a recording region divided into plural zones in its radial direction, and
wherein the reference clock produced by the clock generator has a frequency different from zone to zone.

### Claim 7 (depends on 4)

An optical disk drive according to claim 4, wherein the pre-formatted data includes an address mark, and sector address information subsequent to the address mark, and
wherein the optical disk drive further comprises a window generator for generating a window signal for designating a range in which the address mark is to be detected from the pre-formatted data, by use of the sampling clock.

### Claim 8

A method for processing reproduction data in an optical disk drive for handling an optical disk in which a sector as a recording unit is formed by a header region and a data recording region subsequent to the header region, and the header region has a recording density different from the recording density of the data recording region, comprising the steps of:
reproducing the pre-formatted data from the header region in the sector, and for reproducing data from the data recording region of the sector;
generating a reference clock with a frequency corresponding to a reproduction frequency of the data reproduced from the data recording region in the sector;
dividing the reference clock in accordance with the ratio between the recording density of the header region and the recording density of the data recording region, so as to generate a sampling clock with a frequency corresponding to the reproduction frequency of the pre-formatted data reproduced from the header region; and
detecting the sector mark from the pre-formatted data reproduced in the data reproducing device, by use of the sampling clock.

### Claim 9 (depends on 8)

A method for processing data in an optical disk drive according to claim 8, wherein the pre-formatted data includes an address mark, and sector address information subsequent to the address mark, and
wherein the method further comprises a step of generating a window signal for designating a range in which the address mark is to be detected from the pre-formatted data, by use of the sampling clock.

### Claim 10

A method for processing data in an optical disk drive for handling an optical disk in which a sector as a recording unit is formed by a header region where pre-formatted data including a sector mark for indicating a leading position of a sector and a data recording region subsequent to the header region, comprising the steps of:
obtaining information about a ratio between the recording density of the header region and the recording density of the data recording density;
reproducing the pre-formatted data from the header region in the sector, and for reproducing data from the data recording region of the sector;
generating a reference clock with a frequency corresponding to a reproduction frequency of the data reproduced from the data recording region in the sector;
dividing the reference clock in accordance with the ratio between the recording density of the header region and the recording density of the data recording region, so as to generate a sampling clock with a frequency corresponding to the reproduction frequency of the pre-formatted data reproduced from the header region; and
detecting the sector mark from the pre-formatted data reproduced in the data reproducing device, by use of the sampling clock.

### Claim 11 (depends on 10)

A method for processing data in an optical disk drive according to claim 10, wherein the pre-formatted data includes an address mark, and sector address information subsequent to the address mark, and
wherein the optical disk drive further comprises a window generator for generating a window signal for designating a range in which the address mark is to be detected from the pre-formatted data, by use of the sampling clock.