Experiments results of mid-infrared 4.65m radiation with second harmonic generation (SHG) in AgGaSe2 crystals from a 9.3m pulsed TEACO2 laser are introduced. Based on the principles of nonlinear optics and laser frequency doubling
the pulsed TEA CO2 laser was improved for its output beam quality which made it the whole way to meet the basic requirements of pumping laser source in frequency doubling experiment and then took this laser source as fundamental wave to perform the research works for the SHG. Results show that the same AgGaSe2 crystals made by the different manufacturers displays the different surface damaged characteristics
but the resemblance to them is bulk damaged threshold values higter than surface one. The frequency-doubled maximal single pulse energy 12.9 mJ and average power 940 mW were obtained.