LOCAL DETECTING METHOD FROM OPTICAL FIBER

摘要

PURPOSE:To improve the efficiency of local detection by contacting a dispersing medium with the bending part of an optical fiber and detecting leaked light by a photodetector through the dispersing medium. CONSTITUTION:The dispersing medium 7 reflects incident light irregularly in its inside and a material such as acrylic resin or vinyl is used for the medium 7. The efficiency of incidence can be increased by forming a recessed curve surface so as to lap the bending part 3b of the optical fiber 3 as the dispersing medium 7. Since the incident light is reflected three-dimensionally irregularly in the medium 7, leaked light from the bending part 3B reaches the photodetec tor 8 through the whole contact surface between the bending part 3B and the medium 7. The medium 7 is fitted to the bending part 3B with about 30 deg. inclina tion in the right direction so that the output of the photodetector 8 is maxi mized.