“…It is widely used in sonar and piezoelectric products, Q-switches, high speed photography shutters, electro-optical modulators, and frequency harmonic generation lens. Large size KDP crystal components with high surface form accuracy are required for making the Pockels cells in the Inertial Confinement Fusion (ICF) devices [1] . KDP is believed to be the most difficult-to-cut material, due to its delicate and unique characteristics including the combination of softness with brittleness, anisotropic performances, tendency for deliquescence and sensitivity to temperature change [2,3] .…”