Q: What’s Calcium fluoride used for?

Calcium fluoride is often used in spectroscopic windows and lenses due to its high transmission from 250nm to 7μm. Its low absorption and high damage threshold makes it a popular choice for excimer laser optics. Calcium fluoride's low index or refraction allows it to be used without an anti-reflective coating. The Knoop hardness of calcium fluoride is 158.3. Calcium Fluoride (CaF2) Windows manufactured from vacuum UV grade calcium fluoride are commonly found in cryogenically cooled thermal imaging systems.

Uni-Optics provide artificially-crystallized calcium fluoride components available in UV grade and IR Grade.

Specifications:
 
Material: Calcium Fluoride single crystal ( UV or IR)
Diameter Tolerance:  +0.0, -0.1mm
Thickness Tolerance: ±0.1mm
Clear Aperture: >85%
Parallelism: 3 arc minute
Surface Quality: 60-40 scratch and dig
Wavefront Distortion: per 25mm @633mm
Bevel: Protective ( <0.2mm x 45° )
Coating: Optional
 
Standard CaF2 Window
 
Round Shape:
Φ4x0.5  Φ6x1  Φ8x1    Φ10x0.5  Φ10x0.5  Φ12.7x1  Φ15x1  Φ18x1  Φ20x2  Φ25x1  Φ25.4x1  Φ25.4x2 
Φ25.4x3  Φ30x2  Φ30x3  Φ38.1x3
 
Note for CaF2 Window:
(1). Please specify IR or UV when ordering.
(2). Custom-made CaF2 windows at any size are available. Besides round, CaF2 windows at shape of quadrate,
      triangular, or other polygonal are available. Uni-optics can provide dia. 150mm max.
(3). Typical thickness is 1mm 2mm, 3mm, 4mm, other thickness from 1.0mm to 20.0 mm is available.
(4). Better bevel is available upon request.
(5). CaF2 Windows with Anti-Reflective(AR)