Method for implementing polarization sensitive optical time domain reflection technology by using piezoelectric ceramic

Abstract

The invention discloses a method and a device which realize the time-domain reflection technique of polarized sensitive lights by utilizing piezoelectric ceramics and are characterized in that an unspinnable piezoelectric ceramic polarization controller is used in a measuring light path, and an optical fiber polarizer is arranged before the piezoelectric ceramic polarization controller and taken as both a polarizer and an analyzer. The implementation method of the invention is that the piezoelectric ceramic polarization controller changes light pulses from a short pulse light signal source into a known polarization state under the control of a computer, injects the light pulses into an optical fiber to be detected, and generates backscattering lights; only a photoelectric detector and an algorithm are needed to detect the polarization state change of the returned backscattering lights, thus realizing the distributed measurement of parameters of the optical fiber and the environment. The method and device do not need mechanically spinning devices, have the advantages of accurate measurement, good repetitiveness and quick and convenient operations, etc., and can be widely used in the distributed measurement of the parameters of the optical fiber and the fields of distributed fiber sensors, etc.

Description

technical field [0001] The invention relates to a method and a device for realizing polarization-sensitive light time-domain reflection technology by using piezoelectric ceramics as a polarization control unit, and belongs to the technical fields of optical fiber communication and optical fiber sensing. Background technique [0002] With the rapid development of optical fiber communication and optical fiber sensing technology, it is very important to monitor optical fiber communication lines and measure external environmental factors by measuring optical fiber parameters. Polarization characteristics are one of the basic characteristics of light. When light is transmitted in an optical fiber, it is affected by the parameters of the fiber itself (such as inherent birefringence, twist rate, and polarization mode dispersion, etc.), and its polarization state will change. At the same time, changes in the external environment Bending, twisting, and stress changes in the optical f...

AI Technical Summary

Problems solved by technology

This use of a mechanically rotated polarizer to change the input polarization state poses many problems in practice: To extract light from the fiber and inject it back into the fiber through the rotating polarizer, a pair of self-focusing lenses must be used (like figure 1 The self-focusing lenses 4 and 5, and figure 2 The self-focusing lens 25 and 26)

The axial offset and angular inclination of the self-focusing lens group itself will bring unstable additional coupling loss, while the rotation of the polarizer will cause the lateral offset of the light, and different polarization states have different insertion losses, etc. These factors Seriously affect the accuracy and repeatability of the measurement; in addition, due to the slow mechanical rotation speed, this also affects the measurement speed

[0007] Due to the above shortcomings, in the nearly 20 years after P-OTDR was proposed, no new substantial progress has been made in its research and application.

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