The zinc selenide material is a yellow transparent polycrystalline material having a crystal grain size of about 70 μm and a light transmission range of 0.5-15 μm. The synthesis by the chemical vapor deposition (CVD) method is substantially free of impurity absorption, and the scattering loss is extremely low. Due to the small absorption of 10.6 μm wavelength light, it is the material of choice for making optics in high power CO2 laser systems. In addition, it is also commonly used in different optical systems throughout its transmission range.
The zinc selenide material is highly resistant to thermal shock, making it the best optical material in high power CO2 laser systems. The hardness is only 2/3 of the multi-spectral grade ZnS. The material is soft and easy to scratch, and the material has a large refractive index. Therefore, it is necessary to plate a high hardness anti-reflection film on the surface to protect it and obtain a high transmittance. The scattering is very low in its usual spectral range. When used as a high-power laser device, it is necessary to strictly control the bulk absorption and internal structural defects of the material, and to use the polishing technique with the least degree of damage and the coating process with the highest optical quality.
Zinc selenide is prepared by reacting zinc chloride, zinc sulfate and the like with hydrogen selenide. Widely used in laser, medicine, astronomy and infrared night vision.