|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 Lenses have one concave and one convex surface. Convex-concave lens is thicker at the center than at the edge, which is positive meniscus lens, usually used to decrease the focal length and increase the NA of system. While, convex-concave lens is thinner at the center than at the edge, which is negative meniscus lens, often used to increase the focal length and decrease the NA of system. The meniscus lens is a useful element to minimize the spherical aberration.
Hangzhou Shalom EO provide the custom meniscus lenses upon customer’s request.
Positive Meniscus Lenses:
Negative Meniscus Lenses: