| 摘要 |
PURPOSE:To record identification information on characteristics of numbers of optical disk by providing an area where the identification signal of a disk manufacturer's serial number is recorded or reproduced outside of the area of a track groove where information is recorded or reproduced concentrically or spirally. CONSTITUTION:An area 1 is a concentric or spiral track groove where an information signal is recorded or reproduced. An area 2 is formed by coating the substrate surface of an optical disk with a magnetic recording medium and sticking a coated magnetic card thereupon, and a manufacturer's serial number, etc., are recorded or reproduced in and from the area. When information is recorded on the magnetic card, a head driving current is varied according to a binary-coded information signal to be recorded to change magnetism directions of the magnetic recording medium, and when reproduced, current changes which occurs on a magnetic head are detected as changes in magnetism direction to read out the information. The identification information on the manufacturer's serial number, etc., is recorded by using a dedicated magnetic head when the information area 1 is inspected while the optical disk is rotated. |
