Optical disc and optical disc device

• US 8,254,240 B2
• Filed: 07/03/2007
• Issued: 08/28/2012
• 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): Feild, Joseph
• Assistant Examiner(s): Heyi, Henok
• Application Number:
  US11/822,241
• Publication Number:
  US 20070274183A1
• Time in Patent Office: 1,883 Days
• Field of Search: 369/275.1
• US Class Current: 369/275.1
• 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 7/24038 Multiple laminated recording layers

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 data storage medium comprising;

at least one recording layer having a track upon which a laser beam is focused during use;

a management area provided on said at least one recording layer, said management area having recorded data representing if another recording layer of a different optical disc format standard with different data capacity is present in said medium,

wherein said another recording layer has different physical structure with different track density, and

wherein said recorded data represents presence and absence of each of at least two different recording layers, wherein in a case that said another recording layer is not present in said medium said recorded data indicates said another recording layer is not present in said medium, and in a case that said another recording layer is present in said medium said recorded data indicates if said another recording layer is read only type or recordable type.

2. An optical data storage medium according to claim 1, wherein said recorded data is assigned a bit 0 if no other recording layer is present in said medium.

3. An optical data storage drive for use with an optical data storage medium according to claim 1 comprising:

a unit for accessing said management area of said at least one recording layer to read said recorded data; and

a unit for accessing said another recording layer based on said recorded data.

4. The optical data storage drive of claim 3, wherein said recorded data is assigned a bit 0 if no other recording layer is present in said medium.