Method for improving pumping efficiency of fiber laser and fiber laser thereof

Abstract

The invention relates to a method for improving pumping efficiency of a fiber laser and the fiber laser thereof, wherein the fiber laser comprises a preceding-stage low-power laser source, a plurality of semiconductor pumping lasers, a fiber beam combiner, an active double-clad fiber and an out isolator/collimator; a pumping light reflector is additionally arranged between the active double-clad fiber and the output isolator/collimator, and comprises a passive double-clad fiber, a clad fiber grating etched in the inner clad of the passive double-clad fiber, and a secondary coating layer for coating the clad fiber grating; the central reflecting wavelength of the clad fiber grating is equal to the pumping laser wavelength, and is in the range of 910-980 nm. The fiber laser adopts the inner clad fiber grating, and can reflect the residual pumping laser powder not adsorbed in the inner clad to the active double-clad fiber, so that the pumping light power can be adsorbed by the active fiber for the second time, and the absorption efficiency of the pumping laser in the fiber laser is effectively improved.

Description

[0001] technical field [0002] The invention relates to a fiber laser, in particular to a method for enhancing the pumping efficiency of the fiber laser and the fiber laser. Background technique [0003] With the continuous development of doped fiber technology, double-clad fiber technology, semiconductor pump laser technology, and fiber combiner technology and other related fields, fiber laser technology is also constantly improving and perfecting. Whether it is a fiber pulse laser, a fiber continuous laser, or a fiber quasi-continuous laser, they basically use the pump laser to inject the cladding of the high-power double-clad doped fiber at the power amplification stage, and the pump light is pumped through the core diameter of the fiber. Absorption, the formation of particle number inversion to obtain optical gain, and realize optical power amplification. [0004] In the current pumping structure, the pumping laser only passes through the active double-clad fiber once,...

AI Technical Summary

Problems solved by technology

The traditional method cannot achieve its complete absorption because: when the length of the double-clad active fiber is short, the loss of the signal light is small, but the absorption rate of the pump light is also small; when the double-clad active fiber When the length is longer, the absorption rate of the pump light is greater, but the loss of the signal light is also greater

This therefore creates a contradiction that prevents adequate absorption of the pump laser light

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