The NIF requires optics produced from large single crystals of potassium dihydrogen phosphate (KDP) and deuterated potassium dihydrogen phosphate (DKDP). Each crystal is sliced into 40-centimeter-square crystal plates. Traditionally DKDP has been produced by methods requiring approximately two years to grow a single crystal. With the development of rapid growth methods for KDP, the time required to grow a crystal has been reduced to just two months. The current rapid growth process produces optics that are up to 66cm (2 ft, 2 in) wide, 50cm (1 ft, 8 in) tall, and weighing 380 kg (840 lbs). NIF requires 192 optics produced from traditionally grown DKDP and 480 optics rapidly grown from KDP. Approximately 75 production crystals will have been grown totaling a weight of nearly 100 tons. (NIF/Lawrence Livermore National Laboratory) #