热条件对KDP晶体激光损伤阈值的影响

Potassium dihydrogen phosphate（KDP）crystals were baked at different temperatures in the same procedure. Samples from similar location of as-grown 500-mm-class KDP crystals were used to measure the transmission spectra and laser damage threshold. The results proved that transmission spectra were not affected by thermal conditioning, and laser damage threshold of samples after annealing at 140℃and 160℃ were not significantly different from the unconditioned sample. However, for samples annealing at 150℃, we measured a 1.4× increase for the laser damage threshold at 1ω. It indicated that the effect of annealing at 150℃ is the best for elevating laser damage threshold.