Assertion: calcium fluoride | /r/ObjectUse | used as a window material
Facets:
value: in the laboratory
type: LOCATION
value: for both infrared and ultraviolet wavelengths
type: TRANSITIVE-OBJECT
value: commonly
type: TEMPORAL
Source sentences:
text: In the laboratory, calcium fluoride is commonly used as a window material for both infrared and ultraviolet wavelengths, since it is transparent in these regions (about 0.15 µm to 9 µm) and exhibits an extremely low change in refractive index with wavelength.