| 摘要 |
PURPOSE:To obtain an optical control element which has a simple constitution, is manufactured easily, and is good in its optical utilizing efficiency by providing a heating element which has an opening part and is heated selectively by an external signal, on a transparent medium whose refractive index is varied by heat. CONSTITUTION:A ring-like thin film resistor 2 of ring-like NiCr, W, etc., having an opening part 4 is provided on a plastic thin plate 1, and the plastic thin plate 1 is placed on it as necessary. A light which is made incident from a direction of A is made incident to a photodetector 6 through the plastic thin plate 1, the opening part 4 and a pin hole 6. When a current is made to flow to the resistor 2, the thin plate being in the vicinity of the resistor 2 is heated, the refractive index drops, the refractive index of the center part of the opening part 4 becomes high relatively, and intensity of a light which is made incident to a photodetector 5 is varied by on and off of a current. In this way, it is possible to obtain an optical control element which has a simple constitution, is manufactured easily, and is high in its optical utilizing efficiency. |
