Doublet lens ,achromatic lens

Key Specifications/Special Features: :
Materials: Bk7, quartz, Caf2, crystal
Diameter: 5 to 500mm
Diameter tolerance: 0.01mm to 0.1mm
Edge thickness: 1mm +/-0.10mm
Focal length: 0.1% to 2%
Surface quantity: 80/50 to 20/10
Centration: 1 to 3 arc minutes
Fringes: 1 to 5
Coating: No or AR