Patent ID: 7782730
Filing Date: 2010-08-24
Classification: G11B

Abstract:
1. An optical-pickup-adjustment optical disk used for adjusting an optical pickup device, wherein: the optical pickup device irradiates an optical disk comprising a plurality of information recording layers formed on a side of an inside surface of a transparent protective substrate with a laser beam, thereby applying the laser beam through the transparent protective substrate to any of the plurality of information recording layers to detect the laser beam reflected from the information recording layer, to which the laser beam is applied, and an optical disk, in or from which information is recorded or reproduced by the optical pickup device, is prescribed by an optical disk standard, which prescribes a maximum-depth information recording layer which is a layer having a maximum depth from an outer surface of the protective substrate, and a minimum-depth information recording layer which is a layer having a minimum depth, which is shallower than the maximum depth, from the outer surface of the protective substrate; the optical-pickup-adjustment optical disk comprising: a transparent protective substrate; and an optical-pickup-adjustment middle-depth information recording layer formed on a side of an inside surface of the transparent protective substrate, the optical-pickup-adjustment middle-depth information recording layer being formed to have a middle depth which is a center of the maximum depth of the maximum-depth information recording layer prescribed by the optical disk standard and the minimum depth of the minimum-depth information recording layer prescribed by the optical disk standard.