Simulation of passive Q- switching laser pulse Characteristics as afunction of output coupler reflectivity

The effect of output coupler reflectivity on characteristics ( energy and duration) of a Passive Q- switching Laser Pulse has been studied theoretically by numerical analysis (rung- kata method) for mathematical description (rate equations model) for temporal performance of crystal Chromium yttrium which was used as a storable absorber material (passive switch ) with neodymium cadimium vanadium laser. The study shows that the pulse energy is increasing with increase of the output coupler reflectivity, while the pulse duration decreasing with increase of the output coupler reflectivity.