Calcium Fluoride (CaF₂) Windows

A CaF₂ window is an optical component made from single-crystal or polycrystalline calcium fluoride, known for its wide spectral transmission range (0.15–9 µm), covering deep ultraviolet (DUV) to mid-wave infrared (MWIR). It features ultra-wide transmission, low refractive index, high laser damage threshold, low dispersion, and low hygroscopicity.

• In deep ultraviolet lithography, CaF₂ is used for projection lens windows in 193 nm excimer laser systems.

• In infrared spectroscopy, CaF₂ windows are commonly used in FTIR spectrometer sample chambers and gas monitoring cells.

• In laser systems, they serve as output windows for high-power excimer lasers.

• In scientific and medical fields, they are applied in multispectral UV-IR microscopes and laser treatment devices.

• In aerospace, CaF₂ is used as a broadband IR window in satellite remote sensing systems.

CaF₂ transmits over 90% in the 2–8 µm mid-IR range even without coatings. It has extremely low intrinsic absorption, reducing thermal effects. Its chemical stability provides excellent resistance to acids and alkalis, allowing long-term use in harsh gas environments. It also has moderate hardness, making it easy to process and coat.

We offer UV AR coatings, IR AR coatings, high-reflection coatings, waterproof coatings, and laser damage-resistant coatings for CaF₂ optical windows.

We can customize any size within a diameter range of 1–1000 mm.
Available shapes include round, square, rectangular, annular, polygonal, and other custom geometries.