| 摘要 |
PURPOSE: To provide an optical head easy to make it thin, having good relative accuracy between a slab type waveguide and a photoelectric conversion means, high availability of light, a few noise and no interference between a focusing error signal and a tracking error signal. CONSTITUTION: Since a slab type waveguide 2 is provided with a wiring 2d to which the electrode of a photodiode 9 is directly joined, high relative accuracy between the slab type waveguide 2 and the photodiode 9 is obtained and a thin optical head is realized by mounting a laser diode 2 and a finite system lens 7 on it. An input hologram coupler 5 and an output hologram coupler 6 are formed in the core 2c of the slab type waveguide 2. A light beam guided in a core 2a is decoupled in an output hologram coupler 4. A light beam reflected by an optical disk 8 is coupled to the core 2c by means of the input hologram coupler 5, decoupled by the output hologram coupler 6 and made incident on the photodiode 9. |
