| 摘要 |
PURPOSE:To attain the real time record/reproduction with high S/N by laminating a reflection layer, a light transmitting material and a metallic thin film successively on a substrate. CONSTITUTION:A reflective thin film 14 containing at least one of metal such as Au, Al, Bi, In and semiconductor mainly is formed on a glass or plastics substrate 1. A single or composite film 15 containing a light transmitting material is formed on the film 14, and a recording material thin film 2 containing at least one of metals such as Au, Ta and a semiconductor is formed on the film 15. A laser light fulx 5 delivered from a laser light source 4 is converted into parallel light fluxes by a lens 6 and stopped down on the film 2 in the form of microspots by a semitransparent mirror 7 and a lens 8. Thus a hole 3 is formed and therefore the film 14 is exposed to the laser light flux which is made incident when the information is reproduced. The reflected light flux is detected by two photodetectors 16 and 17, and a differential output 19 is obtained by a differential amplifier 18. As a result, the noise components produced by the recessing/ projecting surface of the film 2 are offset. |
