High-power slab green laser

Abstract

The invention provides a high-power slab green laser. The high-power slab green laser includes a pump source, a focusing system, a laser resonator and a self-frequency doubling crystal. The self-frequency doubling crystal is a neodymium ion doped calcium borate rare earth salt crystal cut into a slab shape along a direction of a maximum non-principal effective nonlinear coefficient of the crystal.Phase matching of different wavelengths is realized by changing a tangential direction of the crystal so as to realize laser output in 545 nm or 550 nm band. The pump source is a laser diode array having an emission center wavelength of 808 nm or 880 nm. An input cavity mirror and an output cavity mirror are coated with suitable film systems so as to obtain high-power laser output in the 545 nm or 550 nm band. The laser of the invention has the advantages of low laser threshold, high conversion efficiency and output power, and simple laser structure.

Description

technical field [0001] The invention relates to a high-power slab green laser and belongs to the technical field of lasers and nonlinear crystal devices. Background technique [0002] Green light refers to light with a wavelength of 500 nm to 560 nm. Green lasers have been used in both military and civilian fields such as laser display, indication, and blinding weapons. There are two main ways to generate practical green laser light: based on indium (In) doped GaN semiconductor (InGaN) emission and Nd 3+ Doped laser crystal frequency doubled laser. Among them, for InGaN semiconductors, the emission wavelength depends on the concentration of In. At present, the emission wavelength of commercial InGaN semiconductors is below 520nm; while Nd 3+ Doped crystals, such as commonly used yttrium vanadate and yttrium aluminum garnet, have emission peaks around 1064nm, and when they are frequency-multiplied, high-power, high-efficiency 532nm lasers can be obtained. Looking at the g...

AI Technical Summary

Problems solved by technology

This type of laser has the advantages of simple structure, stability, and compactness. This method has the advantages of good mode matching and high efficiency, and is suitable for watt-level low-power laser output. However, the pump light of this structure is focused in the laser crystal. Under the requirements of the requirements, the pump spot is small (on the order of hundreds of microns), the heat generated during the laser process is mainly concentrated in this area, and the direction of the temperature gradient is perpendicular to the direction of light propagation. When operating under thermal load conditions, It will produce serious thermal lens effect and optical distortion effect, which will seriously reduce the beam quality, and even crystal cracking will occur, which limits the further improvement of laser output power

The slab laser can realize the enlargement of the pump spot and the effective transmission of heat through the increase of the heat dissipation area. However, the beam of the traditional slab laser usually transmits in the crystal in an M shape, and the self-frequency doubling of the laser requires strict Phase matching, which means that the traditional method is difficult to apply to the field of self-frequency doubling lasers to increase output power

No report on high-power slab green lasers in the field of self-frequency doubling lasers

Images