| 摘要 |
PURPOSE:To provide the optical head featuring a small size, lightness in weight, high-speed access, low cost and excellent property to be assembled into apparatus. CONSTITUTION:The luminous flux emitted from a semiconductor laser 1 is reflected by a reflection type hologram element 2 formed on an objective lens surface and a total reflection mirror 3 and is further condensed by an objective lens 4 to a recording surface 5, by which recording pits are read out. The return light contg. recording signals is introduced by the hologram formed on the surface of the reflection type hologram element 2 to a multidivision photosensor 6, by which the signals are read. The semiconductor 1 and the multidivision photosensor 6 are disposed in the positions not hindering the respective reflected luminous fluxes according to this constitution and, therefore, the small and light optical head of the high access is provided. |
