Broadband Optical Transmission: Custom CaF2 Infrared Windows
The Vital Role of Calcium Fluoride in Advanced Optical Systems
By Atr Crystal | April 30, 2026
Table of Contents
- Broadband Transmission and Low Dispersion
- Environmental Durability and Laser Damage Threshold
- Precision Custom Optics Manufacturing
- References
Broadband Transmission and Low Dispersion
When engineering multi-spectral imaging systems or high-precision spectrophotometers, identifying a material that maintains transparency across a wide spectrum is a primary challenge. Calcium Fluoride stands out as a premier solution. CaF2 infrared windows offer an extraordinary transmission range, remaining highly transparent from the vacuum ultraviolet (VUV) region at 0.13 µm all the way into the mid-infrared (MIR) range at 10 µm. Furthermore, its exceptionally low refractive index and low dispersion (high Abbe number) make it an ideal choice for minimizing chromatic aberration in complex optical lens assemblies.
Environmental Durability and Laser Damage Threshold
Beyond its optical clarity, the physical properties of the material dictate its real-world applicability. Unlike some infrared materials that degrade rapidly when exposed to humidity, Calcium Fluoride is highly stable and insoluble in water, ensuring long-term reliability in varying environmental conditions. Additionally, it exhibits a remarkably high laser damage threshold and extremely low birefringence. This makes CaF2 infrared windows not only suitable for thermal imaging sensors but also perfectly equipped to serve as protective laser windows for high-power Excimer lasers operating in the UV spectrum.
Precision Custom Optics Manufacturing
Because optical system housings and focal requirements vary drastically, standard-sized blanks are often insufficient. Sourcing high-quality raw materials must be paired with stringent fabrication tolerances. At Atr Crystal, we cultivate superior-grade optical crystals and provide end-to-end fabrication. We deliver highly customized CaF2 infrared windows, wedges, and spherical lenses. Our processing capabilities ensure strict dimensional tolerances, exquisite surface flatness, and minimal scratch-dig ratios, enabling your sophisticated optical instruments to perform flawlessly.
