| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a system and a method, for monitoring of the opening and shutting operation of a lid, whose detection accuracy, durability and reliability are enhanced. SOLUTION: An apparatus is composed of a lid 1 which is installed at an object, to be monitored, so as to be capable of being opened and shut, of a fiber for a sensor, of an optical fiber cable which connects the fiber for the sensor to a monitoring center and of a detection device which detects a change in the transmission loss or the reflection loss of transmitted light. The fiber for the sensor is formed in such a way that an optical fiber core 4 is wound on a cylindrical fiber drum 2 a plurality of numbers of times. The lid 1 is opened and shut, the cylindrical fiber drum 2 is deformed elastically, a change in the transmission loss or the reflection loss, of the optical fiber core, generated by changing the bending curvature of the wound optical fiber core 4 is detected, and the opening and shutting operation of the lid is monitored.</p> |
