ATHERMALIZATION OF AN OPTICAL PARAMETRIC OSCILLATOR

摘要

A method for thermally stabilizing an optical parametric oscillator (OPO) (10) to maintain constant optical path length for stable high power output places a beam dump (32) outside an OPO cavity (18). The OPO (10) has a nonlinear crystal (22) within cavity (18) for splitting a single input pump beam (14) into lower energy signal and idler beams (16, 18). The method includes providing a cavity exit port for unconverted pump and generated idler beams, and absorbing unconverted beams in beam dump (32). The method includes athermalization by actively cooling surfaces used as an optics mounting base, and athermalization by constraining the size of cavity (18) by using thermally stiff members, guiding pins or rails, or by using bimetallic materials with different expansion.