Windows for CO2 lasers are used either for protecting sensitive and/or expensive optics, or for separating areas with different gas pressures. In all applications, high transmittance and low absorption are needed in order to minimize distortion of the laser beam. Therefore, such windows usually consist of ZnSe substrates with AR-coatings on both surfaces (the same as focusing lenses).
*Ophir Optics meets ROSH directive according to China ROHS regulation and ROHS2 directive 2011/65/EU