| 摘要 |
PURPOSE:To reduce insertion loss and correctly monitor the change of light signals by reflecting the light emitting from a light transmission path on a photo detector surface through an optical medium and detecting the absorption light produced at the time of performing this reflection. CONSTITUTION:Light emitted from a light transmission path 1 enters a photo diode 3 through a prism 10 and the reflected light enters an optical transmission path 2 through the prism 10. The use of this prism enables the insertion angle of the transmission paths to be taken freely to a certain extent and enables the provision of the transmission paths to be made easier. In addition, even if the axes of the transmission paths are inclined to the surface of the diode 3, the light entering the semiconductor assumes the angle close to perpendicular with respect to the semiconductor surface on acount of a high refractive index of the semiconductor, thus it is efficiently detected with the diode 3, producing an electric output between electrodes 4, 5. If a Schottky barrier type is used as the photo diode 3, the reflection may be accomplished efficiently by the Schottky metal 6. |
