Study On Wide-temperature-range And Uncooled Q-switched-Laser

The design of uncooled solid-state laser by multi-wavelength point combination for application in wide temperature range has been presented in this thesis.Diode-pumped solid-state laser have high peak power,low energy consumption,easy miniaturization and other advantages,widely used in military weapons,laser ranging,laser ignition,optical fiber communications and other fields.In order to improve the stability of the laser in different temperature,the most commonly used methods are water cooling,thermal electric cooler(TEC)cooling and inert gas packaging.However,the water-cooling and TEC cooling require additional refrigeration equipment,which is contrary to the needs of miniaturization,inert gas packaging also exist the problems of pollution on the passivation material.So,develop and produce the laser for different temperature ranges which is small and high stability of the output has important significance.In this paper,the theoretical simulation and experimental were combined.Based on the drift characteristics that the wavelength and energy with temperature,we selected different wavelengths point stack and optimized pumping source structure,the result shows that the laser can be output stably in wide temperature range.The main research results are summarized as follows:1.Chose different wavelength points.Through the combined results of Matlab simulation,results show that: 798,800,802,804 nm wavelength points can achieve a stable output of the pump light in 35~55?.When four array work simultaneously,the instability of energy is less than 10%,while the array switching is less than 45%.2.Designed the structure of the pumping source and simulated by Ansys.The results show that when the four arrays simultaneously,the overall temperature is about 10?,while the one array is about 2?,which can realize natural cooling.3.Selected the parameters of saturated absorber and designed the whole structure of the system.According to the rate equation of passively Q-switching,we formulate the inter pulse time and the number of pulses.Emphatically we analyze the output due to pumping width,the reflectivity of output mirror and the initial transmission of saturated absorber.Through the experiment,we verified the correctness of the analysis results.4.Set up the experimental platform and tested.The wavelength and energy output varies with temperature were tested,results showed that the laser of 1064 nm can be stabilized output in the temperature of 35 ~ 55? without cooling,the overall output energy instability is less than 12%.