Double polarized light polarization-preserving fiber polarization eliminator

Abstract

The invention discloses a double polarized light polarization-preserving fiber polarization eliminator, and belongs to the technical field of communication. The polarization eliminator comprises three sections of polarization-preserving fibers with lengths of l1,l2 and l3 respectively, the polarization-preserving fibers with lengths of l1,l2 and l3 are melted and butted in turn, and the double refraction main axis of the polarization-preserving fiber of the rear section and the double refraction main axis of the polarization-preserving fiber of the adjacent front section form an included angle of 45 degrees along the same direction in turn, wherein l3 is equal to 4l1, l2 is equal to 2l1, delta nbl1 is more than or equal to Ldc, the delta nb is the difference of the refractive indexes of the two main axes of the polarization-preserving fibers, and the Ldc is the decoherence length of a light source. Compared with the prior art, the polarized light obtained by the polarization eliminator is closer to natural light, and the polarization eliminating result is more ideal; and the polarization eliminator has simple structure, clear principle and wide application range.

Description

technical field [0001] The invention relates to a polarization-maintaining optical fiber depolarizer, in particular to a dual-polarized polarization-maintaining optical fiber depolarizer, which can depolarize input dual-polarized linearly polarized light, and belongs to the technical field of communication. Background technique [0002] In fiber optic gyroscopes, single-mode fibers were initially used. However, in the single-mode fiber coil, due to bending, torsion, external stress and temperature changes, there are two orthogonal directions. Refraction or elliptic birefringence. The birefringence in single-mode fiber coils is usually distributed non-uniformly and asymmetrically, so that two counterpropagating light waves will experience different birefringence when propagating in the coil, and this time-varying birefringence will produce non-reciprocal Polarization error. [0003] The emergence of polarization-maintaining fiber provides a solution to signal attenuation a...

AI Technical Summary

Problems solved by technology

Since the current depolarizer cannot achieve an ideal depolarization effect, the amount of information it transmits, the measurement accuracy, and the measurement stability cannot meet the requirements of some special fields or intensive reading applications.

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