Keywords: KDP crystal.jpg A large single crystal of monopotassium phosphate KDP KH<sub>2</sub>PO<sub>4</sub> exhibits optical birefringence as demonstrated by National Ignition Facility scientist Terry Land https //www llnl gov/str/September03/pdfs/09_03 pdf 2003-09-05 Lawrence Livermore National Laboratory LLNL PD-USGov Crystals Lawrence Livermore National Laboratory Monopotassium phosphate Refraction |