Material BK7 Dimension Tolerance +0.0/-0.2mm Thickness Tolerance ±0.2mm Clear Aperture >90% Flatness λ/8@632.8nm per 25mm range Wedge <1 arc minute Surface Quality 60/40 Coating S1: Partial reflective coating, AOI 0degS2: AR coating, AOI 0deg Damage Threshold >5J/cm2, 20ns, 20Hz, @1064nm

An output coupler is a partially reflecting dielectric mirror used in a laser cavity. It transmits a part of the circulating intracavity power for generating a useful output from the laser. A low transmission output coupler leads to a low laser threshold, but also possibly to poor laser efficiency if ...