Corner pumping method for plate strip and its solid laser gain module

Abstract

An angle pump method and its solid laser gain module used in strips is to apply an angle pump structure in which the pump light source is put at the corners of the strip, so the pump light will emit into the strip from its corner plane. Center of the strip contains one or more doped areas and the surrounding linking are not doped. Most of the pump light is restricted in the strip absorbed many times due to the complete reflection, so as to get a rather long absorption length and high absorption efficiency. Strips are in the structure of doped at the center not doped around to ensure the pump light is absorbent at the strip center, reducing thermal lens effect and stress birefringence effect, avoiding strip distortion.

Description

technical field [0001] The invention relates to a solid-state laser pumping method and a solid-state laser gain module, in particular to a pumping method of a gain medium with a slab structure and a solid-state laser gain module, which can be applied to high-power solid-state lasers and solid-state laser amplifiers . Background technique [0002] In high-power solid-state laser devices, rod-shaped or slab-shaped gain media are generally used. Slab media has advantages over rod media. For example, by selecting the material of the slab to have a relatively high refractive index, the medium for cooling the slab has a relatively low refractive index, so that the laser beam forms a zigzag optical path due to total reflection inside the slab. This optical path is called a Zig-Zag optical path. The zigzag optical path homogenizes the optical inhomogeneity in the thickness direction of the slab, reduces the thermal lens effect caused by it, and eliminates the birefringence effect...

AI Technical Summary

Problems solved by technology

But the downside of this invention is that in order to keep the thickness of the slab from being too large, it is impossible to couple more pump light into the inside of the slab, which makes it difficult to scale the laser to high power

In patent 6,134,258 (USA), a transverse edge pumping structure is adopted to absorb the pump light in the width direction of the slab instead of the thickness direction, which effectively increases the absorption length, but when using a gain medium with a lower absorption coefficient, This structure can not get a higher absorption efficiency

[0004] For high-power lasers using quasi-three-level materials (such as Yb:YAG materials), in order to lower the lasing threshold, the doping concentration must be very low, resulting in a very low absorption coefficient

In this case, the absorption efficiency of the existing pump structure is not sufficient

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