Semiconductor side pumped solid-state laser

Abstract

The invention relates to a solid-state laser, and in particular relates to a semiconductor side pumped solid-state laser. The semiconductor side pumped solid-state laser comprises a laser module, a resonant cavity and a cooling system as well as a beam expander, wherein the resonant cavity is an approximate semi-concentric cavity formed by an all-reverse mirror, a micropore diaphragm and an output mirror, the all-reverse mirror is a plano-concave mirror with a radius of curvature being 4-6m, the output mirror is a plano-concave mirror with a radius of curvature being 0.6-0.8m, and the beam expander is arranged on an output light path of the output mirror. The semiconductor side pumped solid-state laser has the advantages of high stability, beam quality and peak power.

Description

technical field [0001] The invention relates to a solid-state laser, in particular to a semiconductor side-pumped solid-state laser. Background technique [0002] At present, in the application fields such as laser marking and surface treatment processing, semiconductor side-pumped solid-state lasers occupy most of the market. This type of laser utilizes the characteristic that the output wavelength of the semiconductor laser matches the absorption wavelength of the crystal to obtain an order of magnitude higher conversion efficiency than lamp pumping. Side pumping achieves high-power pumping and high-power laser output. Currently, this type of solid-state laser is commonly used between 50-100W. At the same time, Nd:YAG can obtain higher intracavity energy storage, narrow pulse width and high peak power due to its longer spontaneous emission lifetime, and is especially suitable for surface processing of metal materials and engraving at a certain depth. Its key component, t...

AI Technical Summary

Problems solved by technology

The cavity mirrors at both ends of the flat cavity adopt plane mirrors. Although the cavity type is easy to adjust, the raw materials are convenient to process, and the divergence angle is small, there are many defects.

First of all, due to the mismatch between the curvature of the cavity mirror and the radius of curvature of the Gaussian beam generated in the cavity, the diffraction loss and geometric loss are large, which increases the loss in the cavity, directly leads to the decrease of laser output power and the increase of threshold, and indirectly reduces conversion efficiency

Secondly, the mode selection ability of the flat cavity is poor, and it is easy to generate multi-mode oscillation, which reduces the beam quality and is very unfavorable to laser processing

At the same time, improper selection of the diameter and position of the aperture diaphragm will also affect the output of the fundamental mode

Finally, as a critically stable cavity, the adjustment accuracy of the flat cavity is high, and the laser output will be seriously affected by vibration and other external forces, and the optical path will undergo irreversible changes

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