17 May 2010 material BK7
Diameter 25.0 +0-.025 mm
Thickness 3 ± 0.5 mm
Min. clear aperture >85% of diameter
Transmission >90% average within specified range
Attenuation >99% average within specified range Specifications
Substrate material UV Grade Fused Silica or BK7
Diameter 25.0 +0~-.025 mm
Thickness 3 ± 0.5 mm
Min. clear aperture >85% of diameter
Transmission >90% average within specified range
Attenuation >99% average within specified range
Angle of incidence 0° ± 5°
Coating Technology Electron beam evaporation, dielectric multilayers
Surface quality 20/10
Coating quality 40/20
Wedge <3 minutes
Wavefront distortion ≤1λ @ 633nm per 25mm
Humidity resistance Per MIL-C-675A
Abrasion resistance Per MIL-C-675A
Optimum temperature 23°C
Temperature limits -50°C to 100°C | 
