Positive meniscus (convex-concave) lens, which is thicker in the middle than at the edges and cause light rays to converge, such lens is designed to minimize spherical aberration. It’s often used in conjunction with other lenses to decrease the focal length to increase the numerical aperture (NA) for an optical system. When used to focus a collimated beam, the convex side of the lens should face the light source to minimize spherical aberration. Since a positive meniscus lens has a greater radius of curvature on the concave side of the lens than on the convex side, real images can be formed.Lenses in H-K9L (N-BK7), UV fused silica, CaF₂, ZnSe & Germanium are available in our catalog and OEM need is welcome.
| Material：H-K9L (CDGM) | EFL Tolerance：±1% |
| Design Wavelength：587.6nm | Centration：≤ 3' |
| Dimension Tolerance ：+0.0/-0.1mm | Surface Quality：40/20 |
| CT Tolerance：±0.1mm | Bevel：0.2mmX45° |
| Irregularity：λ/4@632.8nm | Coating：See details in the list |
| Clear Aperture ：> 90% |
