Optical fiber length measuring device and method

Abstract

The invention discloses an optical fiber length measuring device. The optical fiber length measuring device comprises a laser power source, an optoisolator, a first optical fiber coupler and a second optical fiber coupler. The laser power source is connected with the optoisolator which is connected with the first optical fiber coupler, the first optical fiber coupler is connected with the second optical fiber coupler, and the second optical fiber coupler is connected with an optical fiber to be measured. The optical fiber length measuring device further comprises a first optical detection amplifying system and a second optical detection amplifying system which are connected with the second optical fiber coupler and an external data collector. The optical fiber length measuring device manufactured through the technical scheme and the method can carry out measuring conveniently and reduce cost. By means of the device, the length of the optical fiber can be quickly measured, the longer the optical fiber is, the more convenient the accurate measuring is, but cost cannot be increased accordingly; the structure is simple, an ordinary optical passive device and a semiconductor light source are adopted, and cost is low.

Description

technical field [0001] The invention relates to the technical field of laser measurement and testing, in particular to an optical fiber length measuring device and method. Background technique [0002] At present, the conventional measurement device for the length of communication optical fiber on the market is Optical Time Domain Reflectometer (OTDR). Due to Rayleigh scattering, some faint light will return to the OTDR. Calculate the time it takes from sending a signal to returning a signal, and then determine the speed of light in the fiber to calculate the fiber length. [0003] Due to the influence of noise in the test of OTDR, the Rayleigh scattering power at a certain point in the fiber is a random process. Since the backscattered light signal is extremely weak, to know the general situation of this point, the method of statistical averaging multiple times is generally used to improve the signal-to-noise ratio to reduce the influence of the inherent random noise of t...

AI Technical Summary

Problems solved by technology

This leads to a long test time, generally requiring a waiting time of tens of seconds

In addition, when measuring long-length optical fibers, such as optical fibers over 200 kilometers, an OTDR with a large dynamic range is required. The current situation is that the market price of an OTDR with a normal dynamic range of 30db has dropped to an acceptable level for ordinary users. However, the price of OTDR equipment with a large dynamic range such as 40db or more is still relatively high

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