Optical Material Selector for UV, Visible & IR Applications
Selecting the correct optical material is critical to optical performance, durability and cost.
This interactive optical material selector helps engineers and designers identify suitable materials
for UV, visible and infrared applications based on wavelength, environment, temperature,
mechanical strength and operating conditions.
FAQ
FAQ
Q: Do optical coatings affect material choice?
Yes. Optical coatings can significantly influence both optical performance and durability. Anti-reflection (AR) or broadband AR (BBAR) coatings are commonly used to improve transmission and reduce surface reflections, particularly on high-index materials such as Germanium or Silicon.
For harsh or abrasive environments, protective coatings such as DLC (Diamond-Like Carbon) may be recommended to improve scratch resistance, chemical durability and service life. Coating compatibility can vary by material, wavelength and environment, so this should always be considered during material selection.
Q: Are all optical materials suitable for humid or outdoor environments?
No. Some optical materials — particularly IR salts and certain fluorides — are hygroscopic, meaning they absorb moisture from the air. These materials are typically unsuitable for humid, outdoor or marine environments without special protection.
For applications exposed to moisture or cleaning fluids, non-hygroscopic materials such as Sapphire, Fused Silica or Magnesium Oxide are generally preferred. The operating environment should always be considered alongside wavelength requirements.
Q: Can I use the same optical material for visible and IR wavelengths?
In some cases, yes — but not always. Broadband materials such as Sapphire, Zinc Sulphide (multispectral) and certain fluorides can operate across visible and infrared wavelengths. However, many materials are optimised for specific spectral regions.
For example, BK7 and Gorilla Glass are well suited to visible applications but are not suitable for long-wave infrared, whereas Germanium and Silicon are IR-only materials. The selector helps identify materials that match your required wavelength range.
Q: What tolerances and specifications should I consider beyond material selection?
Material choice is only the first step. Final optical performance also depends on surface quality, flatness, thickness tolerance, parallelism and coating specification. Environmental factors such as pressure and temperature may also influence design choices such as window thickness or substrate grade.