A High Stability Fiber Laser

Abstract

The invention discloses a high-stability optical fiber laser comprising a beam combiner arranged in a resonant cavity. The first conical section of the pumped fiber and the coupling region on the signal fiber are fused and coupled to form the beam combiner. The gain fiber in the resonant cavity absorbs the pump light transmitted by the pumped fiber into the resonant cavity through the beam combiner so as to form laser to be outputted. The beam combiner is arranged in the resonant cavity so that the excessively high power pump light can be prevented from being directly injected into the fiber grating, the stability of the laser can be enhanced and the single resonant cavity laser is enabled to output the laser of higher power. Compared with the end surface pump technology, the pump fiber and the side surface of the signal fiber are fused and coupled and the signal insertion loss is almost zero so that the pump efficiency can be greatly enhanced, the heat generated in coupling can be significantly reduced, the optical-to-optical conversion efficiency of the laser can be enhanced, high power output of the optical fiber laser can be guaranteed and the stability of the optical fiber laser can be further enhanced.

Description

technical field [0001] The invention relates to the field of fiber lasers, in particular to a high-stability fiber laser. Background technique [0002] The pump coupler is an important device used in fiber lasers and fiber amplifiers. It can guide single or multiple LD pump lights into the fiber through the pump fiber without affecting the transmission of the main optical path to provide the required power for the laser. The advantage of the pump power. [0003] The manufacturing process of the existing pump coupler products is generally to taper the fiber bundle composed of the intermediate signal optical fiber and the surrounding pump fiber until the diameter of the taper waist is the same as that of the double-clad fiber. Cut off at the end and perform fusion splicing with the double-clad optical fiber. For example, ZL201410224237.8 discloses a (N+1)×1 fiber end-face pumping beam combiner based on optical fiber erosion. The signal input optical fiber disclosed in this p...

AI Technical Summary

Problems solved by technology

Usually, this technology requires a large grinding and polishing angle of the end face of the pump fiber, which puts forward very high requirements for the grinding and polishing process of the fiber end face. Integrity is very difficult. If the pump fiber is damaged, it will lead to the leakage of pump light, which is the main reason for its limitation of coupling high-power pump light.

In addition, the manufacturing process of this kind of side coupler is complicated, and the yield is low, which is not conducive to mass production in the factory; secondly, under high pump power, the optical glue is difficult to withstand its power density, which will cause volatilization or decomposition, which will reduce the coupling efficiency

[0009] In addition, due to the low pump coupling efficiency or high signal loss of the beam combiner formed by the above coupling method, the beam combiner will generate severe heat and be easily damaged during high power output. Therefore, the beam combiner needs to be placed outside the resonant cavity

Since the beam combiner is arranged outside the resonator, the pump light is directly injected into the fiber grating, and the manufacturing process of the fiber grating determines that it cannot bear too high pump power, so this structure limits the development of single-cavity fiber lasers. power development

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