| 摘要 |
PURPOSE:To provide a focusing function with high accuracy and a wide focusing range by providing waveguide type reflecting condensers having respective different focal distances. CONSTITUTION:The waveguide type reflecting condensers 9a, 9b which reflect the left half of the optical axis 10 of waveguide light 8 coupled with and excited on a waveguide layer 3 from a prism coupler 5 are arranged, which converge waveguide light 14. Also, the waveguide type reflecting condensers 12a, 12b which reflect the right half of the optical axis 10 of the waveguide light 8 are arranged, which converge waveguide light 18 on a focal point 13. Two photodetectors 16, 17 are juxtaposed symmetrically to the optical axis component 15 of the waveguide light 14 on the rear side of the focal point 11 so as to be almost perpendicular to the optical axis component 15 of the waveguide light 14 advancing the focal point 11 on a slab surface. Similarly, two photodetectors 20, 21 are juxtaposed symmetrically to an optical axis 19 on the rear side of a focal point 13 so as to be almost perpendicular to the optical axis component 19 of the waveguide light 18 advancing the focal point 13 on the slab surface. Furthermore, the photodetectors 16, 17 are connected to an operational amplifier 22, and also, the photodetectors 20, 21 are connected to a differential amplifier 23. |
