摘要 |
A multilayer optical disk including a plurality of information storage layers to/from which information is recorded and/or reproduced by an optical head. The plurality of information storage layers are stacked through intermediate layers and each information storage layer includes a wobbling track groove. The shape factors (amplitude of wobbling, depth of the track groove and/or slope angle of the side wall of the track groove, etc.) of the track groove of at least one information storage layer of the plurality of information storage layers are different from the shape factors of track grooves of other information storage layers. This allows a satisfactory signal to be reproduced from each information storage layer. <IMAGE> |