The ZNPA13 Zinc Selenide IR Aspheric Lens is a 50.8 mm in diameter with effective focal length of 50.8 mm aspheric lens. Zinc Selenide has wide variety of usage in high power CO₂ laser systems because of its low absorption coefficient and high resistance to thermal shock. ZnSe aspheric lenses provide diffraction limited focusing performance, making it ideal for focusing the output of a CO₂ laser. It is an excellent choice for any IR applications due to its broad wavelength range (0.6 µm to 16 µm).