| 摘要 |
PROBLEM TO BE SOLVED: To speedily inform a user of the contents of the information recorded on an optical disk without reproducing them. SOLUTION: This optical disk has a reflection film 12 formed on the surface in the vicinity of the center hole 11a of a disk substrate 11 and is constituted so that the information can be stored as a pit 12c between a read-in part 12a of the film 12 and a read-out part 12b. A RFID 13 constituted of a coil 14 formed by winding around the vicinity of the hole 11a by one or more times and a IC chip 16 connected to both ends of the coil 14 is arranged on the surface of the film 12 between the edge of the hole 11a and the part 12a. A radial notch 17, which is extended from the inner edge of the film 12 and crosses the coil 14 and the tip of which is separated from the outer edge of the coil 14 by 2.5 mm or longer, is formed on the film 12. An electrically conductive film 18, which shows 0.25 Ω or smaller electric resistance value when the width and length of the film 18 are 1 cm, is formed, directly or while interposing a protection film, on the film 12 between the circle 12d coming into contact with the tip of the notch 17 and the part 12b. |
