Research On Spatial Distribution Of Q-switched Laser Pulse Shape And Detection Technology

In order to research the spatial distribution of the Q-switch laser pulse shape, this paper is from the Q-switch technology theory at first, when the acousto-optic Q DPL laser pulse was detected, it was found that the detected output waveform at different locations in the spot was not the same at the different time and that was because the laser field distribution which is caused by the multi-mode competition in the constantly changing over time and different spaial locations.By the analysis of energy storage and release during the Q-switched process, the algorithm theoretical model of the Q-switched process is built, In the simulation process, the ideal Gaussian beam, uniform beam and second order flattened Gaussian beam are choosen as the pumped beam source, when its pump power and pump radius were changed, the figures of laser field distribution and output power would be obtained. After analysis of the simulation results, it was found that if the pumped beam changed, the laser field distribution would be changed.and if changed the pump power and pump radius, the laser field distribution and the output power of the laser would be also changed at the same time.In order to detect the output waveform of the Q-switched laser at the different locations in the spot at the same time, it should design the super high frequence laser pulse detection circuit, which mainly included detection circuit modules, high-speed sampling circuit modules, FPGA logic control circuit modules, clock generation circuit module, and the external interface circuit modules, then detailed description design principles and design methods of each module in this paper.