CaF₂ is an excellent optical material with the advantages of broad spectral transmission range, high transmittance, low phonon energy, good mechanical strength and good moisture resistance. CaF₂ shows abundant interstitial positions in the fluorite-type cubic lattice structure, allowing rare earth ions with high concentration doping.
Calcium fluoride crystals are widely used in scientific fields such as lasers, infrared optics, ultraviolet optics, and high-energy detectors. In particular, CaF₂ shows good optical performance in the ultraviolet band. CaF₂ exhibits high transmittance and small fluorescence radiation in ultraviolet band witch is an ideal material for UV lasers.