OPTICAL FIBER LOCATOR

PURPOSE:To grasp a secular change by storing past measurement data on an optical fiber cable and comparing this stored data with new measurement data. CONSTITUTION:Light pulses of a laser diode 2 which synchronizes with a clock part 1 are sent out to an optical fiber 4 through a coupler 3. Then, Fresnel reflected light is passed through an avalanche photodiode 5, amplifier 6, A/D converter 7, and adder 8 to remove noises, etc., coded, and processed by a processing part 9 to be displayed on a display part 12. The part data is stored in a memory 10 and the same measurement of the optical fiber is taken repeatedly to obtain current data, which is compared with the past data; and a comparative arithmetic part performs arithmetics 11 regarding the loss of the optical fiber and splice loss and the result is displayed on the display part 12. The locator is provided with the comparative arithmetic functions to represent a secular change in receive waveform, i.e. variation in the characteristics of the optical fiber in clear form.