| 摘要 |
PURPOSE:To improve the utilizing efficiency of light by providing a high- reflectivity film to the rear side of the photoirradiated surface of the optical recording medium. CONSTITUTION:The optical recording medium is constituted by successively laminating the high-reflectivity film 7, a recording film 8 and a protective film 9 on a base material 6. On the other hand, the exit light of a semiconductor laser 1 converges onto the optical recording medium via a collimating lens 2, a polarizing beam splitter (PBS) 3, a lambda/4 plate 4, and a condenser lens 5. Incident light is reflected mainly at the boundary between the high-reflectivity film 7 and the recording film 8. The reflected light travels backward and is reflected by the PBS 3 so as to be made incident to a detecting optical system 10. |
