ouble-concave (DCV).
Material: These lenses are made from soda-lime, borosilicate, or quartz.
Diameter: Ranges from 1-300 mm.
Diameter Tolerance: Maintained within 0.1 mm.
Thickness Tolerance: Controlled within 0.1 mm.
Curvature Radius Tolerance: Usually 0.5, but can reach 0.1% in precision applications.
Centration: Less than 3 minutes of arc.
Clear Aperture: Over 90%.
Beveling: Below 0.2 45 or as per requirements.
Refractive Index: Between 1.4 and 1.6.