| 摘要 |
PURPOSE:To simplify structure greatly and open and close an optical shutter with high efficiency of utilization by arranging two linear light transmissive members so that their slanting surfaces face each other normally across an extremely fine gap, and providing a moving means which allows the slanting surfaces to contact and leave each other. CONSTITUTION:The slanting surfaces 6 and 7 having an angle more than the critical angle are formed at ends of two input-side and output-side linear light transmissive members 1 and 2 made of an optical fiber and face each other normally at an extremely small interval (d). The light transmission member 2 is provided with a heater 8 which allows the slanting surfaces 6 and 7 to contact and leave each other. Light from a light source 5 is normally reflected totally and does not travel forward, but when the heater is put in operation, the light transmissive member 2 expands thermally and the slanting surfaces 6 and 7 come into contact to project the light on the member 2. Consequently, the structure becomes extremely simple and a light singla is transmitted and cut off with high utilization efficiency. |
