| Like to positive meniscus lenses these negative meniscus lenses have one concave and one convex surface. This time the radii are chosen to give an overall negative effect.That is a collimated beam of light will be diverged. Like the positive meniscus lenses they can be used in conjunction with an achromatic doublet to increase the focal length. We can offer custom negative meniscus lenses to meet your requirements or alternatively edge stock lenses for a quick turnaround, please enquire. Please note we also stock a full range of positive meniscus lenses. Specifications: | Material: | B270 | | Diameter: | +0.0 / -0.25 (25mm dia) ± 1mm (60mm dia) | | Back vortex power: (=1/back F.L) | ± 0.06D ( 4D) ± 0.12D (> 40D) | | Surface Quality: | <60-40 scratch/dig | | 
Meniscus Lenses - Negative Type
