... lens,plano-convex lens,bi-concave lens,bi-convex lens,mensicus lens,achro,achromat lens,ball lens,cylindrical lens,spherical lens,aspheric lens ... etc. Specifications:Material: Bk7, Quartz, Caf2, Sapphire. etc.Diameter: .OD:2mm-120mmEdge thickness: 1mm +/- 0.10mm.Focal length: 0.1 ... 50 to 20/10 .Centration: 1 to 3Arc minutesFringes: 1 to 5Clear Aperture>90% of ...