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Product Announcement

Calcium Fluoride (CaF2) Optical Components

03 Feb 2022

Calcium Fluoride (CaF2) is a crystalline material with excellent transmission from the vacuum ultraviolet (VUV) region through to infrared wavelengths. There are different grades of calcium fluoride, with each being dependent on the manufacturing process. 

These include:

  • Standard (infrared) Grade:is made using natural fluorite and, therefore, is the most cost-effective option. However, the natural fluorite can contain impurities that impact its transmission in the UV region. 
  • UV Grade:has minimal impurities within the chemically prepared fluorite and, therefore, has superior transmission in the UV region. UV Grade CaF2 is excellent as an excimer laser optic due to its low absorption, refractive index, and dispersion.
  • Raman Grade:exhibits minimal fluorescence and only has one Raman peak at 321cm-1, which is specific to Calcium Fluoride. With a wide transmission band encompassing VUV to IR, this material is ideal for spectroscopic applications. 

Find out more information by reading our blog, where we bring calcium fluoride into the spotlight. 

Here at Knight Optical, we have a vast range of stock CaF2 components, including Lenses, Prisms and Windows, the latter of which is available in 8mm to 120mm diameters with all Standard, UV, and Raman Grade options. We also stock 38.5mm x 19mm and 41mm x 23mm Drilled Cell Windows for spectroscopic applications. All our current stock CaF2 Windows are uncoated; however, please enquire with our technical sales team if a coating is required. 

Our CaF2 Lenses are available as Standard and UV Grade with focal lengths from 13mm to 467mm, as well as negative focal length options. What's more, we also hold stock of Right-Angle and Equilateral CaF2 Prisms, which are ideal for applications utilising UV through to IR wavelengths. 

Alongside this wide-ranging stock portfolio, we also provide custom-made Calcium Fluoride (CaF2) optical components, including Windows, Lenses, and Prisms with differing dimensions to our stock components. In addition, these customised components include a coating such as an AR coating or beamsplitter and filter coatings dependent on your application. 

Our typical capabilities comprise:


Form error (@633nm)

Centration /parallelism


< 5mm to 250mm

< 0.25 waves

< 1 arcminute

< 60/40

With an on-site, state-of-the-art Metrology Laboratory and dedicated QA department, Knight Optical tests all stock and custom-made optical components against their specification to ensure they meet all requirements. Our equipment includes a Zygo Verifire interferometer for checking surface form error and radii, an Agilent Cary 7000 spectrophotometer for UV and visible transmission/reflections scans, and an Agilent Cary 660 FTIR for infrared transmission measurements.

Contact our UK and USA sales team for further information and help with your enquiries via the below information. 


Europe, UK, Asia & RoW: 


+44 (0)1622 859444 

USA & Canada: 


+1 401-583-7846

Knight Optical Ltd
Roebuck Business Park
ME17 1AB
United Kingdom
Tel: 44 (0)1622 859444
Fax: 44 (0)1622 859 555
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