Extracavity All Solid-state Eye-Safe Raman Laser Based On Ba?NO₃?₂ Crystal Pumped By 1342nm Laser

A diode-side-pump actively Q-switch laser and a first-Stokes eye-safe laser with Ba?NO₃?₂ crystal pumped by 1342 nm pulse laser is studied from theory and experiment, respectively. Stimulated Raman scattering classical theory and the basic structure and theory of the external cavity Raman laser are analyzed. This paper introduces the physical, chemical and optical properties of Ba?NO₃?₂ crystals, the threshold of the external cavity Raman laser with Ba?NO₃?₂ crystal along with the change of reflectivity of output coupling mirror is calculated according to the external cavity laser Raman threshold formula. The rate equations of external cavity Raman laser is implemented to simulated external cavity solid Raman laser based on Ba?NO₃?₂ crystal double pumped by 1.34?m using Matlab software. A diode side-pumped Nd:YAP with b shift cutting laser that can produce single pulse energy of 17.05 mJ of 1.34?m output under the flatflat cavity at a repetition rate of 20 Hz. A BBO crystal was used as E-O Q-switched crystal, according to the theory of ABCD matrix to simulate the flat lumen output characteristic of light, and through the experiment achieved 1342 nm fundamental laser in 1.34?m is achieved with sing pulse energy of 17.05 mJ, highest pulse width of 21.52 ns at 20 Hz frequency. The pulse width got by when insert the polaroid film polarizing film and not is compared in the experiment. The results are the fundamental laser cavity which insert the polaroid can get more narrow pulse width more power density. According to the results of optimization, external cavity solid Raman laser system based on Ba?NO₃?₂ crystals is seted, and in the experiments, to a first stokes light 1562 nm laser output and first-order stokes threshold and light energy, pulse width, and conversion efficiency is got by measured or calculated. In the experiments, knife-edge method is used to measure the light beam quality of the fundamental laser, and the conversion efficiency influenced by beam quality is analyzed, it is concluded that the better beam quality, the higher the conversion efficiency.