| 摘要 |
PURPOSE:To obtain a satisfactory differential effect with an optical-magnetic storage device, by providing two photoelectric converters to receive the luminous fluxes detected by two photodetectors and then amplifying differentially the outputs of those two photoelectric converters. CONSTITUTION:The laser beams which are irradiated to a storage medium 1 having a magnetization facilitating axis in the direction vertical to the film surface and then reflected or transmitted are made incident to a composite polarizer 8. The azimuth angle theta of the polarizer 8 is set at 0 deg.theta<45 deg. to a junction line. The wave detected light passed through each polarizer of the polarizer 8 is made incident to a composite photodetecting element 9 consisting of two photodetecting elements split in the direction equal to that of the junction line of the polarizer 8. Each information signal applied with the photoelectric conversion by the element 9 is fed to a differential amplifier 10, and this differential effect suppresses the effect of the undesired signal light. |
