Specifications
EFL (mm): 250.0
Dia: 50.8
CT: 9.6
ET: 10.3
R1 Radius: 500.0
Material: Pyrex
Specifications: Effective Focal Length (EFL): +/- 1%
Diameter (DIA) +0/- .1
Center Thickness (CT): +/- .2
Cosmetics R1: 40/20
Surface Quality R1: 1 X 1/4 wave @ 546.1nm
Surface Quality R2: Medium Grind
Centering Accuracy: 2 arc minutes TIA
Clear Aperture: 90% of surface area