One of the basic optical elements in Windows optics, usually used as a protective window for electronic sensors or detectors of the external environment. It is used to separate the environment on both sides, such as separating the inside and outside of the instrument, so that the inside and outside of the instrument are isolated from each other, thereby protecting the internal devices. The windows do not change the magnification of the system.
Compared to most materials, calcium fluoride has a low refractive index, high average transmittance, and low chromatic aberration. Calcium fluoride has excellent transmission between 180 nm and 8 μm, and the resulting window is transparent in the UV, visible and IR wavelength range, making it suitable for applications involving multiple wavelengths, such as UV, visible and IR Spectral or fluorescence imaging of wavelengths. The refractive index of calcium fluoride is very wavelength stable: very low chromatic aberration in visible light, Abbe number of 95.31 (64.17 for N-BK7), very suitable for imaging applications; in the infrared region, calcium fluoride has the lowest of all infrared materials The group velocity dispersion is therefore widely used in femtosecond infrared systems.
Calcium fluoride material is easy to deliquescence in the environment of high humidity and high temperature. It is recommended to control the humidity of the use environment to 25% and the temperature to 20°C. After each use of the product, wipe it clean and store it in a dry cabinet to avoid contact with acids. This product is slightly irritating. It is recommended that operators wear protective equipment, avoid direct skin contact, and wash their hands after work.