| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical semiconductor device that is made smaller and thinner to be suitable for surface mounting, etc., highly reliable and inexpensive. SOLUTION: A photodetector 13 is provided in an envelope 12 so that a photodetecting surface 17 is opened on the surface of the envelope 12. A titanium dioxide thin film of a high refractive index and a silicon dioxide film of a low refractive index are laminated alternately on the photodetecting surface 17 of the photodetector 13 by direct deposition. Thus, the photodetecting surface 17 is coated with a filter 18 constituted of a multiplayer film, which reflects light in the infrared region and transmits light in the visible light region.
|
