High-efficiency all-optical-fiber column vector light beam laser

Abstract

The invention discloses a high-efficiency all-optical-fiber column vector light beam laser. Less-mode and long-period fiber bragg grating can realize high-efficiency conversion from a fundamental modeto a first-order mode and has the characteristic of low insertion loss; and by introducing the less-mode and long-period fiber bragg grating into a laser cavity to be used as a mode conversion device, the mode conversion efficiency is improved and intra-cavity loss can be lowered, so that high-efficiency output of the column vector light beam can be realized. The laser comprises an amplifier module used for laser generation and amplification, a resonance cavity module used for realizing laser resonance, a polarization control module used for controlling the intra-cavity laser polarization state, and a mode conversion module, namely the less-mode and long-period fiber bragg grating, used for realizing high-efficiency mode conversion. The column vector light beam output by the laser has thecharacteristics of high efficiency, low threshold value, high purity, mode switchable property and the like, no space coupling structure, high stability, high portability and suitability of productization.

Description

technical field [0001] The invention relates to the field of fiber lasers, in particular to a high-efficiency cylindrical vector beam laser based on a few-mode long-period fiber grating. Background technique [0002] Different from ordinary polarized beams, cylindrical vector light means that the polarization direction on the cross-section of the beam has a cylindrically symmetrical distribution, and its transverse light intensity distribution is circular. Generally, it can be divided into angular and radial polarized light. [0003] The special polarization and amplitude characteristics of cylindrical vector light make it applicable in many fields, such as particle manipulation, material processing, plasma excitation, optical storage, super-resolution microscopic imaging, optical communication and other fields. [0004] Compared with the column vector laser with spatial coupling structure, the all-fiber column vector laser has the characteristics of good portability, good s...

AI Technical Summary

Problems solved by technology

However, in the all-fiber column vector laser reported at present (such as: Chinese patent CN102544999A), most adopt the dislocation fusion splicing coupling of single-mode fiber and few-mode fiber to realize the conversion from fundamental mode to first-order mode, and the mode conversion efficiency is low (less than 20%); and due to the large intracavity loss due to phase mismatch; at the same time, in order to suppress the output of the fundamental mode beam to ensure the output purity of the first-order mode, a high reflectivity output mirror is used, which is difficult to achieve the optimal output The coupling ratio limits the output power; the above reasons lead to higher requirements for the input pump light power, and more importantly, it is difficult to achieve high-efficiency all-fiber column vector laser output

In addition, the amount of misalignment needs to be adjusted manually, which is difficult to control accurately, which increases the complexity and uncertainty of the experiment

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