Optical ZnSe is a zinc selenide crystal material specifically engineered for infrared optical systems operating around 10.6 microns, commonly used in CO2 laser applications. It offers low absorption, high transmission efficiency, and excellent optical homogeneity, making it suitable for laser focusing lenses, output windows, and beam delivery systems. Because ZnSe is a relatively soft crystal, it requires precision polishing and specialized coating to ensure stable performance under high-power laser exposure.