OST Photonics KDP Crystals/DKDP Laser Nonlinear Crystals Potassium Dihydrogen Phosphate (KDP) and Potassium Dideuterium Phosphate (DKDP, KD*P) are among the most widely-used commercial NLO materials. KDP crystals and DKDP crystals are commonly used for doubling, tripling and quadrupling of Nd:YAG laser at the room temperature. In addition, KDP crystals and DKDP crystals are also excellent electro-optic crystals with high electro-optic coefficients, widely used as electro-optical modulators, Q-switches, and Pockels Cells, etc. If you would like to know more about KDP crystals and DKDP crystals prices, please do not hesitate to contact Ost Photonics.