| abstract |
This invention is proposed to smoothly and adequately perform recording and/or reproducing on recording mediums using a biodegradable material as substrate material. This invention makes a recording medium, in a case that the substrate thereof is made of a biodegradable material, hold information, structure or the same indicating that the recording medium is biodegradable. For instance, in a case that this invention is applied to CD, CD-R, CD-RW, identification information indicating that the substrate is made of a biodegradable material is made to contained in a free area for TOC data in the lead-in area as shown in Fig. 4. An optical disc device identifies a disc loaded therein being one that its substrate is made of a biodegradable material by reading out the identification information from the disc. In the case that loaded disc is one that its substrate is made of a biodegradable material, the optical disc device measures the temperature inside the device, and when the temperature becomes close to the glass transition temperature, the recording/reproducing operations to the disc is stopped and the disc is ejected from the device. |