| 摘要 |
PURPOSE:To enable the comparison of an aged change, etc. after the installation by correcting the waveform only of the altered part of an optical fiber and by making use of the past deposited data on the waveform of excepting the altered part. CONSTITUTION:Point C21, C22 show the differential steps due to connection loss of an optical fiber and the inclination to the right of the waveform C2 indicates the attenuation of waveforms, in the waveform C2 of the case when a measuring light is made incident from the incidence end of an optical fiber. The waveform C2 is the waveform of the case of connecting the broken line of the point C31 and C32 are corresponding respectively to points C21, C22. The point C33 is a new connection point and when the waveform C2 and the waveform C3 are compared, there is no alteration in sections L1, L3 and the section L2 of the waveform C2 is divided into sections L4, L5 in the waveform C3. Now, when there is any alteration in one part of the optical fiber, only the waveform of the altered part is corrected against the waveform of before the alteration and the aged change of the optical fiber can be compared so as to make use of the past deposited data for the waveform of excepting the altered part. |
