Optical disc and optical disc device

• US 10,002,634 B2
• Filed: 06/27/2017
• Issued: 06/19/2018
• Est. Priority Date: 02/16/2005
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Nakahara, Hironori, Takeshita, Nobuo, Ogawa, Masaharu
• Primary Examiner(s): Tran, Thang
• Application Number:
  US15/633,938
• Publication Number:
  US 20170294204A1
• Time in Patent Office: 357 Days
• CPC Class Codes: G11B 20/1217 on discs
• CPC Class Codes: G11B 20/1262 with more than one format/standard, e.g. conversion from CD-audio format to R-DAT format
• CPC Class Codes: G11B 2007/0013 for carriers having multiple discrete layers
• CPC Class Codes: G11B 2020/1227 one layer of multilayer disc
• CPC Class Codes: 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
• CPC Class Codes: G11B 7/00736 Auxiliary data, e.g. lead-in, lead-out, Power Calibration Area [PCA], Burst Cutting Area [BCA], control information sector headers or adresses in prepits G11B7/00745; address data in track wobble G11B7/24082
• CPC Class Codes: G11B 7/0079 Zoned data area, e.g. having different data structures or formats for the user data within data layer, Zone Constant Linear Velocity [ZCLV], Zone Constant Angular Velocity [ZCAV], carriers with RAM and ROM areas
• CPC Class Codes: G11B 7/013 for discrete information, i.e. where each information unit is stored in a distinct discrete location , e.g. digital information formats within a data block or sector
• CPC Class Codes: G11B 7/08511 with focus pull-in only
• CPC Class Codes: G11B 7/127 Lasers; Multiple laser arrays lasers per se H01S
• CPC Class Codes: G11B 7/13 Optical detectors therefor
• CPC Class Codes: G11B 7/135 Means for guiding the beam from the source to the record carrier or from the record carrier to the detector
• CPC Class Codes: G11B 7/1392 Means for controlling the beam wavefront, e.g. for correction of aberration optical systems for aberration correction per se G02B27/00
• CPC Class Codes: G11B 7/2403 Layers; Shape, structure or physical properties thereof
• CPC Class Codes: G11B 7/24038 Multiple laminated recording layers
• CPC Class Codes: G11B 7/24041 with different recording characteristics

Abstract

In a multilayer optical disc having information layers conforming to a plurality of different optical disc standards, because the type of each information layer is not recorded in the other information layers, in read and write operations by a compatible optical disc device conforming to a plurality of optical disc standards, every time the information layer being accessed changes, it has been necessary to read the type of the information layer and select a method of generating a tracking error signal adapted to the type of information layer, so access has taken time. In order to solve the above problem, in the optical multilayer disc according to the present invention, having information layers conforming to a plurality of different optical disc standards, in an area in one of the information layers, information about the other information layers is recorded. The time required to access the other information layers can be reduced by using this information to select a tracking error signal generating method.

Claims

1. An optical disc comprising:

a first recording layer, having a track upon which a first laser beam is focused; and

a management area provided on said first recording layer, said management area having recorded information representing if a second recording layer upon which a second laser beam is focused is present in said optical disc and other recorded information representing if a third recording layer upon which a third laser beam is focused is present in said optical disc,

wherein a wavelength of said second laser beam is longer than that of said first laser beam,

wherein a wavelength of said third laser beam is longer than that of said second laser beam,

wherein each of said information comprises two bits,

wherein said information indicating said second recording layer represents absence of said second recording layer by bit values of 00 in a first position,

wherein said information indicating said third recording layer represents absence of said third recording layer by bit values of 00 in a second position.

2. A recording apparatus for recording data on an optical disc according to claim 1, said recording apparatus comprising:

a laser light source for producing a laser beam;

a focusing device for focusing said laser beam on said at least one recording layer of said optical disc;

a photo detector for detecting a return laser beam from said optical disc and generating a data signal responsive thereto,

wherein said focusing device focuses said laser beam onto said management area to read each of said information stored therein.

3. A playback apparatus for reproducing data recorded on an optical disc according to claim 1, said playback apparatus comprising:

a laser light source for producing a laser beam;

a focusing device for focusing said laser beam on said at least one recording layer of said optical disc;

a photo detector for detecting a return laser beam from said optical disc and generating a data signal responsive thereto,

wherein said focusing device focuses said laser beam onto said management area to read each of information stored therein.

4. An identifying apparatus for identifying the type of an optical disc according to claim 1, said identifying apparatus comprising:

a laser light source for producing a laser beam;

a focusing device for focusing said laser beam on said at least one recording layer of said optical disc;

a photo detector for detecting a return laser beam from said optical disc and generating a data signal responsive thereto,

wherein said focusing device focuses said laser beam onto said management area to read each of information stored therein.