Material - N-BK7, CDGM H-K9L, Fused silica, CaF2, Sapphire
Design index (bk7) - 1.51680 for BK7, 1.45846 for Fused Silica
Diameter tolerance - +0.0, 0.15mm -
Paraxial focal length - ±2% -
Centration - <3' -
Clear aperture - 80% -
Surface quality - 60-40 scratch and dig -
Surface irregularity - < λ/4 -
Protective bevel - 0.25 + 0.25, -0.0mm