A polarization-maintaining optical fiber side-view imaging axis fixing method and device

Abstract

Provided is a side-view imaging azimuth-aligning apparatus for a polarization maintaining fiber. The apparatus is formed by an optical path portion, a rotation control portion, and an azimuth-aligning program, two optical paths arranged in the vertical manner and the rotation control portion are fixed on the same mechanical platform, the rotation control portion and a host computer are connected via an RS232 interface, and the optical paths and the host computer are connected via a PCI bus. A side-view imaging azimuth-aligning method for the polarization maintaining fiber includes four steps. According to the method and the apparatus, azimuth aligning is accomplished by directly employing the symmetry of a characteristic curve, the construction of a standard curve is not needed, the calculation amount is reduced, the speed and the precision for azimuth aligning are improved to a certain extent, and the problem that the standard curve is not universal for different types of fibers is well solved.

Description

technical field [0001] The invention relates to a polarization-maintaining optical fiber side-view imaging axis fixing method and device, and belongs to the technical fields of optical fiber communication and optical fiber sensing. Background technique [0002] A general axisymmetric single-mode fiber can transmit two linearly polarized orthogonal modes or two circularly polarized orthogonal modes at the same time. The two orthogonal modes will propagate forward at the same speed in the fiber, so the polarization state will not change during the propagation. Due to the existence of non-axisymmetric and bending in the actual optical fiber, the two orthogonal modes will be coupled during the propagation process, and the result is that the polarization state of the light wave changes during the propagation process. For this reason, a polarization-maintaining fiber that can maintain the polarization state of light waves has been developed, that is, a polarization-maintaining fi...

AI Technical Summary

Problems solved by technology

For the POL axis-fixing method, the light intensity at the center of the light intensity distribution after the optical fiber is used as the feature point, and the POL curve is drawn using the feature points after the fiber rotates one cycle, and then the axis is fixed by calculating the correlation coefficient between the original POL curve and the standard POL curve, mainly The disadvantage is that it is necessary to construct a standard curve for each type of fiber, which reduces the technical versatility

PAS alignment technology completes the alignment by comparing the light intensity profile, the main disadvantage is that it is only applicable to specific types of optical fibers

The basic principle of the five-point and five-finger light intensity distribution fixed axis method is the same as that of the POL fixed axis method, except that the feature point extraction method is different. to an image that meets the requirements

Images