| 摘要 |
PROBLEM TO BE SOLVED: To reduce the measuring time by reducing the measuring frequency when obtaining a measurement waveform of loss characteristics of an optical fiber with a prescribed accuracy. SOLUTION: An optical pulse generating part 10 repeatedly generates optical pulses of a prescribed wavelength at prescribed intervals. A return light detecting part 20 allows the optical pulses from the optical pulse generation part 10 to be incident on the optical fiber 1, detects the return light, and converts it into electric signals. A waveform processing part 30 forms a measurement waveform expressing the loss characteristics of the optical fiber from the detection signal from the return light detecting part 20. In this case, a divided movement average part 50 further divides the measured waveform added and averaged by an averaging circuit 302 and converted into logarithm by a logarithmic conversion circuit 304 into a plurality of regions according to the SN ratio, and moving-averages each point in the respective regions along the waveforms. As a result, the SN ratio of the measured waveform is improved so that the waveform in the distal part becomes clearer compared with that processed only by the adding average and the result is displayed on the display 40. |
