| 摘要 |
PROBLEM TO BE SOLVED: To perform access from an optical head by providing an optical disk drive and a multiplex data surface optical medium in an optical data storage device and providing the surfaces of plural substrate members separated by air gaps in the medium. SOLUTION: This medium 12 is provided with a substrate 50 and laser light beams enter the medium 12 from the substrate 50. The substrates 50, 56, 61, 68 and 74 are provided by an optical transmissive material such as glass and a high polymer material, etc., through respective outer diameter rims 52, 58, 64 and 70 and inner diameter rims 54, 60, 66 and 72. The substrate 56 is a first light transmissive member, and on the substrate 56, a first writable data recording layer is provided and a dielectric layer is provided. Further, the substrates 62 and 68 are second and third light transmissive members and a writable data recording layer and the dielectric layer are provided on the substrates 62 and 68 as well. Also, the substrate 74 is a protective medium provided with the writable data recording layer. Spaces 78 are provided among the substrates 50, 56, 62, 68 and 74 by the outer diameter rims and the inner diameter rims, surrounding pressure is balanced, respective data layers are highly transmissive and thus, the optical data storage medium having multiples laminated layers is obtained. |
