| 摘要 |
PURPOSE: To obtain an optical pickup device in which the number of parts is reduced so as to make an optical system compact and simple and of which light utilization efficiency is higher than a conventional hologram pickup. CONSTITUTION: A luminous flux separating element 2 has a function for separating light (light source light) from a light source 1 and reflected light (detection light) from a recording medium 6. The light (light source light) from the light source 1 is made incident (condensed) on the recording medium 6 through a coupling lens 3, a deflecting prism 4 and an objective lens 5. Meanwhile, when the reflected light from the recording medium 6 is made incident through the objective lens 5, the deflecting prism 4, and the coupling lens 3, the reflected light is separated from the light source light and made incident on a photodetector 8 in a converged light state through a diffraction means 7. |
