Pockels cells are used to change the polarization state of light with a voltage applied to the electrodes of electro-optic crystal such as DKDP (KD*P).
DKDP (KD*P) based Pockels cells are used for Q-switching applications from the 400 nm to about 1.1 μm. Most of commercial flashlamp pumped Nd:YAG lasers and low repetition rate DPSS Nd:YAG lasers are equipped with DKDP (KD*P) based Pockels cells for laser cavity Q-switching.