| 摘要 |
PROBLEM TO BE SOLVED: To reduce noise in a reproduced signal by eliminating return light of reproducing laser light reflected by the surface of a translucent substrate and boundaries of other layers. SOLUTION: Optically readable information can be reproduced and/or recorded on this optical information medium. An outer circumferential parts of disks 1 and 1' are covered with a coating member 15 having a material of absorbing a reproducing laser light. A refractive index of the coating member 15 for covering the outer circumference of the translucent substrate 5 of this disk 1 shall preferably be larger than a refractive index of the translucent substrate 5 of the disk 1. In addition, it is preferable that such a coating member 15 is formed to reach an outer circumferential part of an information recording area (r) of the disk 1. |
