| 摘要 |
PURPOSE:To obtain a photo distributing circuit of low transmission loss and easy assembling by letting the end faces opposing to the incident and exit faces of a faces of a focusing type optical transmission body of the specified refractive index distribution and length be plural faces with reflecting film. CONSTITUTION:An optical transmission body 1 is formed of the glass material comprising dipping a glass bar containing thallium ions into high temperature potassium molten salt or other and its refractive index distribution in the direction perpendicular to its optical axis 3 reduces in approximate proportion to the square of distance. Its length is made odd times of 1/4 the wavelength of propargation light in the transmission body 1. Incident light from the optical fiber 11 in the optical axis direction perpendicular to the end face 2 of this transmission body 1 reflects on the reflecting end faces 4 thru 7 of different angles deposited with a reflecting film at the opposing end face and emits from the different regions of the end face 2 without being diffused by the refractive index distribution. Further, because of the specified length of the transmission body, the spot light entering the end face 2 from the fiber 11 emits as spot light from each region of the end face 2 after the reflection. Hence, the incident light is distributed into the optical fibers 12 thru 15 provided at these points with low loss and easy of assembling and adjustment. |
