Multi-source interference sensing system

Abstract

The invention relates to a multi-source interference sensing system. The scheme provided by the invention is characterized in that the multi-source interference sensing system comprises at least two laser sources with different wavelengths, two photoelectric detectors, a preceding stage optical fiber coupler, a backward stage optical fiber coupler and a sensing optical fiber, wherein all the laser sources are connected at the same side of the preceding stage optical fiber coupler; one port at the other side of the preceding stage optical fiber coupler and the two photoelectric detectors are connected at the same side of the backward stage optical fiber coupler; and two ends of the sensing optical fiber are respectively connected with two ports at the other side of the backward stage optical fiber coupler to form an optical closed loop. By adoption of the multi-source interference sensing system, the problems that an interference signal is not enough in strength and is not stable caused by a double refraction phenomenon generated in the optical fiber randomly in the traditional optical fiber interference system are solved, in this way, the optoelectronic system disclosed by the invention has the advantages that the interference signal is stable and is not affected by environmental factors.

Description

technical field [0001] The invention relates to optical fiber sensing technology, in particular to a measurement system for optical fiber interference signals. Background technique [0002] The invention is mainly based on the principle of optical interference. In the optical fiber interference system, two beams of light from the same laser source propagating in forward and reverse directions form interference in the same optical fiber, that is, in an optical closed circuit. When the optical closed loop is disturbed by the outside world, the optical path along the positive and negative directions will be affected. Although the two beams are affected equally, the time it takes for this effect to reach the detector is different. The interference light intensity measured on the detector will be affected, causing a corresponding change in response. [0003] Taking the traditional optical closed loop interference ring as an example, such as figure 1 As shown, the light emitte...

AI Technical Summary

Problems solved by technology

This will make the system unable to work stably and reliably

[0011] The above problems are unavoidable problems in all optical fiber systems that apply the interference principle; these factors will cause a series of problems such as instability of optical fiber interference signals, deterioration of signal-to-noise ratio, and increased false alarm rate and false alarm rate of the system.

Images