| 摘要 |
PURPOSE:To discriminate visually the surface and the rear side by laminating and providing a recording layer on both faces of a substrate, and providing a discriminating means which can discriminate these two recording layers. CONSTITUTION:A recording layer is provided on both faces of a substrate, and constituted so that its recording layer can be discriminated visually, by discriminating information for discriminating the two recording layers, for instance, by coloring 25 a part or the whole of the surface within a range which does not obstruct recording and reproduction, or providing a notch, etc. on the surface. In such a way, in case of a recording/reproducing device which can record and reproduce information only from one face of an optical card, the reproduction can be executed by setting the face in which specified information to be reproduced is recorded, to the side of an optical head, therefore, the retrieval time of information can be shortened. |
