Material:Glass Usage:Optical Structure:Plano-convex Shape:Spherical Substrate Material:N-BK7 Diameter:25.4mm Diameter Tolerance:+0.00/-0.05mm or customer design Surface Quality:80-50,60-40,40-20,20-10,10-5 Surface Flatness:1/4lambda or customer design Surface Irregularity:1/2lambda or customer design Focal length tolerance:+/-1% Clear Aperture:>90% of Diameter Chamfer:0.05-0.5mmx45degree Centration:3 Arc Min Show More