| 摘要 |
PROBLEM TO BE SOLVED: To increase the arrival angle of infrared rays and to reduce the loss of the infrared rays at a time when the infrared rays are incident by a method wherein the front face, which receives the infrared rays, of an infrared light guide member is formed to be a concave curved surface. SOLUTION: The front face of an infrared light guide member 1 is formed to be a concave curved surface 11. In addition, its rear face is formed to be a concave curved surface 12 so that the tip convex part 41 of a photodetector 4 is fitted. Infrared rays S which are emitted from a remote control device are incident on the concave curved surface 11 at the front face of the infrared light guide member 1 so as to be received by the tip convex part 41 of the photodetector 4. In this manner, since the front face is formed as the concave curved surface 11, the arrival angle θ2 of the infrared rays can be increased, and the loss of the infrared rays at a time when they are incident can be reduced. In addition, since the rear face of the infrared light guide member 1 is formed as the concave curved surface 12 so that the tip convex part 41 of the photodetector 4 can be fitted, the infrared light guide member 1 and the photodetector 4 can be positioned surely when the tip convex part 41 of the photodetector is fitted. |
