The Influence Of Heat Transfer Condition On Laser Crystal Thermal Effect And The Simplified Calculation Method For Thermal Optical Path Difference

Diode-pumped all-solid-state lasers(DPSL) has lots of advantages, such as compact structure, high stability, high optical-optical conversion efficiency. It is widely used in communication, national defense, industry, medical treatment and scientific research. Laser crystal is the core of DPSL and it decides characteristics of output laser. In recent year, to obtain high output powers from continuous-wave end-pumped solid-state lasers, thermal effects must be considered, which impact optical performance of laser. With the development of high-power semiconductor laser technology, high power laser diode-pumped solid state lasers have been a research focus. These studies mainly focused on how to raise effectively the output power and to improve quality of output light, on which the most important influence is from the thermal effect of laser crystal. In this paper, temperature fields and thermal effects of laser crystal was studied. First, through the analysis of working condition of end-pumped laser crystal, the non-adiabatic boundary conditions of laser crystal was established. Then, the analytical expression of laser crystal temperature field was obtained. The influence of heat transfer condition on thermal deformation, thermal stress and thermal focal length were analyzed respectively. And the simplified calculation methods for thermal optical path differences of laser rod and slab were also established.