Newport MKS Parallel Optical Window, UV Fused Silica, 50.8 mm, λ/20, 650-1000 nm 20QW40-30AR.16

The 20QW40-30AR.16 Laser-Grade Parallel Window is parallel to less than 30 arc sec for minimal transmitted beam deviation. This 2 inch (50.8 mm) diameter UV Grade Fused Silica window is 10 mm thick. It has Newport's AR.16 broadband NIR antireflection coating for a 650 to 1000 nm wavelength range. For demanding applications, such as intracavity laser applications, holography, and multiphoton imaging, this window has a λ/20 surface flatness and 10-5 scratch-dig significantly reducing unwanted scatter. Ideal for UV, Laserline & Broadband Applications UV Grade Fused Silica is synthetic amorphous silicon dioxide of extremely high purity providing maximum transmission from 195 to 2100 nm. This non-crystalline, colorless silica glass combines a very low thermal expansion coefficient with good optical qualities, and excellent transmittance in the ultraviolet region. Transmission and homogeneity exceed those of crystalline quartz without the problems of orientation and temperature instability inherent in the crystalline form. It will not fluoresce under UV light and is resistant to radiation. For high-energy applications, the extreme purity of fused silica eliminates microscopic defect sites that could lead to laser damage.