| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical circuit element and a light transmitting/receiving device of a low cost whose noise is small and the number of components is small. SOLUTION: The light transmitting/receiving device (30) has a light emitting element (11) which emits light of a first wavelength, and a light receiving element (13) which receives light of a second wavelength. Further, the device has an optical circuit element which injects light from the optical fiber (12) to the light receiving element. The optical circuit element has a first convex lens (32) which makes divergent rays from the light emitting element (11) parallel light in a base substrate (31) formed of an optical material; diffraction grating surface (33) which receives parallel light from the first convex lens surface (32), projects its zero-order transmitted light to the optical fiber (12), and emits primary diffraction light projected from the optical fiber (12) to a prescribed direction; a reflection surface (34) which injects light from the diffraction grating surface (33) to the light receiving element (13); and a second convex lens surface (36) which collects light from the reflection surface (34) to the light receiving element (13). |
