Disc-shaped recording medium, disc driving device and disc producing method

Abstract

With the disc-shaped recording medium, or the disc manufacturing method according to the present invention, for both the single-layer disc and the multi-layer disc, a recording layer L, which is to be the first layer, is at the same distance, along the direction of disc thickness, from the surface of the cover layer CVLs on which falls the laser light. For the multi-layer disc, the second layer Land the following layer(s) are formed at the locations which are closer to the cover layer CVLs than the first layer L. Management information may be recorded by mobbling grooves, each layermay have tert areas, defect information, a replacement area. Thus, it is possible to improve compatibility, reliability and accessibility between a single-layer disc and a multi-layer disc. The spherical aberration for the recording/reproducing light may be controlled with respect to the selected layer.