What is ISO 22531 about?  
Calcium Fluoride is commonly used in the manufacture of optical components which use the ultraviolet (UV) spectrum but is also highly suited to infrared (IR) wavelength. The hardness of Calcium Fluoride is another feature that makes it preferable to barium fluoride in many applications.
ISO 22576 specifies calcium fluoride used in the infrared spectral range from 0,78 μm to 10μm. The material specified in ISO 22576 can also transmit light in other spectral domains (ultraviolet and visible).  
Who is ISO 22531 for? 
ISO 22531 on calcium fluoride used in the infrared spectrum is useful for: 
- Opticians
- Optical instruments manufacturers
- Safety regulatory bodies
- Optical glass testing engineers
 Why should you use ISO 22531?  
 ISO 22576 applies to the classification of calcium fluoride used in the infrared spectrum.
Calcium fluoride is used for infrared optical systems such as optical windows and lenses. The specifications for its use in the infrared spectrum are different than those used in the visible range. The crystal structure of calcium fluoride is referred to as the fluorite structure. A single crystal of calcium fluoride is composed of a crystal lattice with no grain boundaries. The birefringence of the crystal depends on the light propagation direction with respect to the crystal axis. By adopting ISO 22531, manufacturers can demonstrate the reliability of their optical materials and build trust in their use throughout the optical industry.
