Structure Design And Thermal Analysis Of Thin Tube Laser Gain Module

Solid-state lasers are widely used in fields such as national defense construction,national economy,scientific research and development,and daily life.Thin tube laser gain modules are critical components for solid-state lasers to achieve high beam quality and high average power laser output.With the continuous development of lasers in the direction of high power and miniaturization,higher requirements have been put forward for the mechatronics-hydraulic integrated design of thin tube laser gain modules.This paper carries out research on thin tube laser gain modules from theoretical analysis,design and testing.The main research contents are as follows:(1)According to the requirements of laser transmission for the assembly,cooling,sealing and power supply of the thin tube laser gain module,the overall structure of the thin tube laser gain module was determined,the structure layout and technical parameters of the thin tube and pump were selected,and the optical path transmission and thermal management program were formulated.(2)The structure of the pump module and the gain medium module are designed.The pump module adopts one-way six cooling channels,which solves the cooling problem of the LD module.In order to ensure high-quality laser output,a low-stress clamping structure for optical lenses and a double-thin tube centering adjustment structure with conical surface centering and end adjustment are designed to achieve the 20 ?m coaxiality assembly requirement of the double-thin tube.(3)In order to eliminate the adverse effects such as thermal lens,stress,depolarization and birefringence caused by the thermal effect of the gain module,the cooling channel on the inner and outer walls of the thin tube was designed,the cooling channel theoretical model was established,and the radial and axial temperature distributions of the thin tube laser gain medium were analyzed.The results show that the radial and axial temperature distributions of the gain medium show a linear relationship in the steady state.When the inner wall and outer wall cooling water flow rate reach 2 m/s and 1 m/s or more,the temperature distribution is the most uniform,which provides a basis for the cooling water supply of the laser.(4)A cooling condition test system for the inner wall of a thin tube was built,and the relevant factors affecting the cooling effect of the thin tube were analyzed.The results show that when the thin tube gains medium water supply cooling,the cooling water flow is the key factor affecting the cooling effect.The larger the cooling water flow,the better the cooling effect,and the pressure has little influence on the cooling effect.Through the above research,this paper has completed the structural design and assembly of the thin tube laser gain module,solved the requirements of optical transmission for the thin tube assembly,cooling,sealing and power supply,and achieved the high power and miniaturization design goals of the thin tube laser gain module.