A quasi-cavity equipped on both sides with mirrors that have a transparent hole at their centers is used for a back-reflection regenerative pumping system for a thin-disk solid state laser instead of the multipass pumping system. We have investigated thermo-optical and thermo-mechanical properties of the quasi-cavity by employing finite element analysis (FEA) numerical method in a cylindrical and a rectangular quasi-cavity. Temperature, displacement distribution and variation of refractive index of the rectangular quasi-cavity in different pump powers have been calculated for several materials. We recommend a combination of diamond/YAG crystal in making quasi-cavity for better performance in high power quasi-end-pumped thin disk laser.
