| 摘要 |
PURPOSE:To secure the interchangeability of an optical card by providing an identification information part on which the kind and the optimum laser power are recorded on the optical card, and controlling the laser power by reading the information in the identification information part by an optical pickup. CONSTITUTION:On the optical card 1, an ID part 2 on which the information of a track address, etc., is recorded and the identification information part 4 on which a user area to record the information by a user, the kind of the card 1 and the optimum laser power for the recording, reproduction, and erasure of the information are recorded are provided. The identification information in the information part 4 is read by a pickup 21 arranged so as to be confronted oppositely with the identification information part 4, and the laser power to be projected from the pickup 21 on the card 1 is controlled. Thus, it is possible to perform the recording, the reproduction, and the erasure of the information by the optimum laser power and to secure the interchangeability of the optical card. |
