Patent classifications
G11B7/24041
OPTICAL DISC AND OPTICAL DISC DEVICE
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.
Optical recording medium
There is provided an optical recording medium including: three reproduction layers, wherein reflectance R1, R2, and R3 of the three reproduction layers on a side of a surface irradiated with reproduction light is equal to or greater than 5%, and wherein any absolute value of a difference delta R between two selected from the reflectance R1, R2, and R3 is equal to or less than 7%.
Optical recording medium
There is provided an optical recording medium including: three reproduction layers, wherein reflectance R1, R2, and R3 of the three reproduction layers on a side of a surface irradiated with reproduction light is equal to or greater than 5%, and wherein any absolute value of a difference delta R between two selected from the reflectance R1, R2, and R3 is equal to or less than 7%.
Optical recording medium
Provided is an optical recording medium capable of suppressing sticking between the optical recording mediums in a case where a plurality of optical recording mediums are superimposed on each other. The optical recording medium includes an optical recording medium main body having a first surface and a second surface, and a first convex structure layer provided on the first surface. The first convex structure layer has a surface provided with a plurality of first convexities, and includes first particles and a first resin material. The plurality of first convexities are formed by a part of the first particles included in the first convex structure layer, the part of the first particles protruding from the surface of the first convex structure layer.
Optical recording medium
Provided is an optical recording medium capable of suppressing sticking between the optical recording mediums in a case where a plurality of optical recording mediums are superimposed on each other. The optical recording medium includes an optical recording medium main body having a first surface and a second surface, and a first convex structure layer provided on the first surface. The first convex structure layer has a surface provided with a plurality of first convexities, and includes first particles and a first resin material. The plurality of first convexities are formed by a part of the first particles included in the first convex structure layer, the part of the first particles protruding from the surface of the first convex structure layer.