| 摘要 |
PURPOSE:To judge the presence of the bending radiation loss of an optical fiber and the bending position of said fiber, by a method wherein two or more kinds of lights mutually different in a wavelength are incident to the optical fiber and the difference between transmission losses obtained with respect to respective wavelengths is calculated. CONSTITUTION:A light source 1 has a light source 11 of a wavelength lambda1 and a light source 12 of a wavelength lambda2 and the lights 21 from the light source 1 pass through a transmission mirror 3 to be incident to an optical fiber 7 to be measured from the end surface thereof. The reflected lights 22 from the optical fiber 7 due to back scattering are detected by detectors 41, 42 corresponding to the wavelength thereof and subjected to data processing in an operational processing part 5 to be displayed on a display 6. When the plot of the difference between transmission loss coefficients of the optical fiber calculated by differentiation operation becomes a predetermined value or less, it can be judged that bending radiation loss is generated and, from the plot position to the graph thereof, a bending generating position is determined. |
