plano-convex,double-convex,plano-concave,double-concave Material:BK7,Fused Silica,ZnSe,ZnS,Si,Ge,etc.,Specification for lenses (Cylindrical Lenses)Material:BK7 ( Or Fused Silica)Design Wavelength:546.1nm Flatness: Diameter Tolerance: +0.0, -0.15mm Thickness tolerance : ±0.2mm Clear Aperture: >80% Surface Quality: 20-10 scratch and dig Bevel: 0.25 mm x 45° Paraxial Focal Length:±2% Specifications: ...