| 摘要 |
PURPOSE:To obtain an optical information reproducing device which can reduce the quantity of return light to a light source, by providing a device which compensates double refraction of an information recording medium. CONSTITUTION:The radiant light from a light source 10 is transmitted through a collimator lens 11, polarizing beam splitter 12, optical system 13, and a beam splitter 14 successively and is condensed to a minute diameter by a condenser lens system 15 and is irradiated to an information recording medium 16. The reflected light from the information recording medium 16 which is transmitted through the beam splitter 14 passes the optical system 13 and is reflected on the polarizing beam splitter 12 and reaches a photodetector 17 to read information recorded on the information recording medium 16. Double refraction of the information recording medium 16 is compensated in a certain degree by the condenser lens system 15 and a control system consisting of the optical system 13, the beam splitter 14, the polarizing beam splitter 18, photodetectors 191 and 192, and a driving part which are provided between the condenser lens system 15 and the polarizing beam splitter 12, thus reducing the quantity of return light to the light source 10. |
