1)Dielectric Laser Mirror Material: BK7 or UV grade Fused Silica Dimension Tolerance: +0.0/-0.2mm Thickness Tolerance: +/-0.2mm Clear Aperture: >90% Flatness: λ/10@632.8nm for flat mirror, λ/4@632.8nm for spherical mirror Wedge: <1 arc minute Surface Quality 60/40 scratch and dig Coating Dielectric HR coating on one surface, R>99.5% for random polarization, rear surface uncoated Damage Threshold: >10J/cm2, 20ns, 20Hz, @1064nm 2)Metal Coated Mirror Material: BK7 Dimension Tolerance: +0.0/-0.2mm Thickness Tolerance: +/-0.2mm Clear Aperture: >90% Flatness: λ/10@632.8nm for flat mirror, λ/4@632.8nm for Spherical mirror Wedge: <1 arc minute Surface Quality : 60/40 scratch and dig Coating Metal coating on one surface, rear surface uncoated Damage Threshold: >1J/cm2, 20ns, 20Hz, @1064nm Protected Aluminum Coating: Ravg>87%@400-1200nm Protected Silver Coating: Ravg>95%@400-12000nm Protected Gold Coating: Ravg>98%@2000-12000nm