Research On 946 Nm All Solid State Pulsed Laser Based On Electro-optic Q-switch

The 946 nm laser with narrow pulse width has been widely used in the fields of ozone detection,environmental monitoring,laser radar,health care,laser processing,laser ranging and so on;In the meantime,the laser with a wavelength of 473 nm can be obtained by intracavity frequency doubling of 946 nm laser,which is one of the most effective methods to obtain 473 nm laser,and the 473 nm laser has been widely used in optical storage,laser medicine,color display,underwater communication and detection;In addition,the 946 nm laser could be used as pump light.Therefore,946 nm laser has attracted wide attention.But the stimulated emission cross section of 946 nm laser is too small,meanwhile,there is re-absorption loss,severe thermal effects and parasitic oscillations in the cavity,these factors hinder the development of 946 nm lasers.At present,research about 946 nm laser is mostly using LD Array end-pumped Nd:YAG crystal,combined with Q-switched device to obtain 946 nm pulse.However,the doping concentration of Nd3+ and size of the Nd:YAG crystal limit the peak power of 946 nm pulse.In order to obtain 946 nm laser pulse with higher single pulse energy and peak power,we used pulsed LD Arrays side-pump high-doped,large-size Nd:YAG crystal rod,and use the MgO:LN crystal based on transverse electro-optic effect to carry out the study of electro-optic modulation Q 946 nm all solid state pulsed laser.The following works have been done in this paper:? After analyzing the mechanism of the thermal effect of laser crystal,we use MATLAB to simulate the process that multi-directional LD Array side-pump Nd:YAG crystal rod.Then,we explore the factors that influence the intensity distribution of light,the light power absorbed by crystal at each points and the temperature gradient in the crystal to find kinds of ways to reduce the severe thermal effects of 946 nm laser.?We use LD pulse side-pump Nd:YAG crystal rod to obtain 946 nm pulse,and explore the affect of the repetition frequency of LD signal and transmittance of output mirror on power of laser pulse.?Two kinds of Q-switch 946 nm all solid state pulsed lasers were designed by using two MgO:LN crystals cut at 45°and Brewster angle separately.Then the unpolarized 946 nm pulse with single pulse energy of 6.74 mJ,peak power of 0.242 MW was obtained,and the p-polarized 946 nm pulse with single pulse energy of 4.71 mJ,peak power of 0.224 MW was obtained.Finally,the parameters of the resonator were optimized and we analyzed the influences of pulse repetition frequency and pump power on the performance of the output pulse.