CaF2 is commonly used for applications requiring high transmission in the infrared and ultraviolet spectral ranges. Its extremely high laser damage threshold makes it useful for use with excimer lasers. The material exhibits a low refractive index, varying from 1.35 to 1.51 within its usage range of 180 nm to 8.0 μm. Calcium fluoride is also fairly chemically inert and offers superior hardness compared to its barium fluoride, magnesium fluoride, and lithium fluoride cousins.

Like all plano-concave lenses, these lenses have negative focal lengths and can be used to diverge collimated beams; in this case, the curved surface should face the source in order to minimize spherical aberration. In addition, they can be employed to offset the effects of spherical aberration caused by other lenses in an optical system.

• Uncoated Vacuum-Grade Calcium Fluoride Substrate
• Ø12.70mm or 25.40mmVersions Available
• Broadband AR Coating for the 3 - 5 μm Range
• Focal Lengths from -18.0 mm to -500.0 mm
• Ideal for use with Excimer Lasers