Device and method for detecting fault position of multi-mode optical fiber by using optical resonant cavity

Abstract

The invention discloses a device and a method for detecting a fault position of a multi-mode optical fiber by using an optical resonant cavity, and relates to the technical field of optical fiber fault detection. According to the technical scheme, laser light emitted by a semiconductor laser enters a single-mode optical fiber coupler, output light passes through an upper branch and a lower branch respectively, light in the upper branch enters a multi-mode optical fiber to be detected, the light returns after Fresnel reflection at a fault point, part of the light on the left end face of the optical fiber to be detected returns to the single-mode optical fiber coupler and then returns to the semiconductor laser to generate chaotic laser, and the other part of light is subjected to Fresnel reflection on the left end face of the multi-mode optical fiber to be detected and then reaches the fault point of the optical fiber to be measured again, so that the left end face of the multi-mode optical fiber and the fault point form an optical resonant cavity, the process is repeated in the optical fiber to be detected to generate resonance, the lower branch of the single-mode optical fiber coupler is connected with a photoelectric detector and then connected with an oscilloscope for detection and self-correlation operation, and the position of a resonance peak in self-correlation is the distance between the left end face of the multi-mode optical fiber to be detected and the fault position. According to the detection method, the fault of a multi-mode optical fiber can be rapidly and accurately measured, the detection has no blind area, and the structure is simple.

Description

technical field [0001] The invention relates to the technical field of optical fiber fault detection, in particular to a detection device and method for realizing the fault location of a multimode optical fiber by using an optical resonant cavity. Background technique [0002] Since multimode fiber has a larger core diameter, which means it supports more transmission modes, it is inseparable from the participation of multimode fiber in short-range local area networks, data centers, laser ignition, engineering applications and experiments. However, during use, multimode fiber will cause information transmission failure and ignition failure due to fiber contamination and fiber connection failure, and even cause serious damage and loss. Therefore, the fault detection of multimode fiber becomes more and more important. . [0003] At present, multimode optical fiber fault detection is usually measured by the pulse-of-flight method. The typical measuring instrument is an optical ...

AI Technical Summary

Problems solved by technology

[0005] In order to solve the problem that the pulse method measurement cannot satisfy both long-distance and high precision in multi-mode optical fiber fault position detection, and the chaotic optical time-domain reflectio...

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