|Type||Positive/Negative meniscus Lens||Material||BK7, UV FS, CaF2, BaF2, ZnSe ect.|
|Diameter Range||1mm -300mm||Diameter Tolerance||+0.0/-0.1mm|
|Clear Aperture||>90%||Thickness Tolerance||±0.1mm|
|Focal Length Tolerance||±2%||Surface Quality||40/20 S/D|
|Irregularity||λ/4 @ 633 nm (λ/8 optional)||Centering||2 arc min|
Meniscus Lens has one concave and one convex surface. Convex-concave lens which is thicker at the center than at the edge, defined as positive meniscus lens, is usually used to decrease the focal length and increase the NA of system; while convex-concave lens which is thinner at the center than at the edge, defined as negative meniscus lens, is often used to increase the focal length and decrease the NA of system. Meniscus lens is a useful element to minimize the spherical aberration.
Hangzhou Shalom EO provides custom meniscus lenses upon customer’s request.
Positive Meniscus Lenses:
Negative Meniscus Lenses: