AR-coated windows from Newport come in 12.7, 25.4, or 30 mm sizes

Newport FemtoOptics ultrathin antireflection (AR)-coated windows minimize positive group delay dispersion (GDD) in optical systems using ultrafast lasers with femtosecond pulses. Designed for the 620–980 nm range and an angle of incidence of 0° to 20°, the windows come in 12.7, 25.4, or 30 mm sizes with a thickness of 0.5 or 1 mm.
Newport (MKS Instruments)
Irvine, CA
www.newport.com