| 摘要 |
PURPOSE:To provide the resistance to electromagnetic force without an electric power source by operating a light emitting element at a receiving end, sending the light thereof through an optical fiber to a sensor part and transmitting the sensed measurement information to the receiving end through another optical fiber. CONSTITUTION:Light is fed from a light source 5 through an optical fiber 31 to a sensing part and when there is no mirror or the mirror surface does not face the sensor part, the reflected light thereof does not enter a condenser lens 21 and does not return to a receiver 4. However, when the mirror surface faces the sensor part and when the mirror comes to the position where the light enters the lens 21, the light which is sent by the fiber 31 and is reflected by the mirror is transmitted through a fiber 32 and is detected with the receiver 4. |
