Laser damage threshold measurements of anti-reflection microstructures operating in the near UV and mid-infrared

Surface relief textures fabricated in optical components can provide high performance optical functionality such as antireflection (AR), wavelength selective high reflection, and polarization filtering. At the Boulder Damage XXXIX symposium in 2007, exceptional pulsed laser damage threshold values were presented for AR microstructures (ARMs) in fused silica measured at five wavelengths ranging from the near ultraviolet (NUV) to the near infrared. For this 2010 symposium, NUV pulsed laser damage measurements were made for ARMs built in fused silica windows in comparison to untreated fused silica windows. NUV threshold values are found to be comparable for both ARMs-treated and untreated windows, however the threshold level was found to be strongly dependent on the material and surface preparation method. Additional infrared wavelength damage testing was conducted for ARMs built in four types of mid-infrared transmitting materials. Infrared laser damage threshold values for the ARMs treated windows, was found to be up to two times higher than untreated and thin-film AR coated windows.