| 摘要 |
PURPOSE:To prevent noise and to facilitate the adjustment of optical axis by providing grooves along the optical axis to a pair of opposing supporting members, fixing an optical transmission fiber and a photodetection fiber in the grooves and detecting the change in the quantity of the light transmitted therein. CONSTITUTION:Grooves 16, 17 are formed along the optical axis to supporting members 12, 13 projecting from a base plate 10 consisting of plastics, and the bottom surfaces 161, 171 of the grooves are formed into a V shape. A fiber 18 for optical transmission and a fiber 21 for photodetection are fixed in the V-grooves 161, 171. The light from a light emitting element 25 is transmitted by the fiber 18, emits from an optical transmission surface 183, is made incident to the photodetection surface 211 of the fiber 21 and is transmitted to a photodetector 26. The signal corresponding to the change in the quantity of light when a member 9 to be detected shuts off the optical path is transmitted from the photodetector 26 to an input circuit 8. Thereby, noise is prevented and the adjustment of the optical axis is facilitated. |
