GATE OPENING DEGREE SENSOR FOR OPTICAL FIBER AND GATE OPENING DEGREE MONITOR FOR OPTICAL FIBER USING IT

摘要

PROBLEM TO BE SOLVED: To provide a highly reliable gate opening degree sensor for optical fiber requiring no power supply, and to provide a gate opening degree monitor using the sensor.;SOLUTION: When a gate 20 descends, a flexible moving material 2 also descends and is accumulated on a saucer 3 from the part coming into contact with the saucer 3. When the material 2 is accumulated on the saucer 3, the weight on the saucer 3 increases and a beam 4 bends in accordance with the weight. Since the accumulated amount of the material 2 is proportional to the descending amount of the gate 20, the opening degree of the gate 20 can be indicated by processing the strain caused by the bending of the beam 4 as the change of the wavelength of reflected light by using fiber Bragg gratings 6a and 6b by means of a signal processing section. When the gate 20 ascends, the strain can also be indicated similarly. Since the fiber Bragg gratings 6a and 6b are used for the beam 4 constituting the gate opening degree sensor 1 which detects the opening degree of the gate 20, the sensor 1 is high in reliability and does not require power supply.;COPYRIGHT: (C)2004,JPO