Meniscus Lenses

Meniscus LensesFeatures: High Precision Dimension Control, Optional Substrate Material,M inimizes spherical aberration, Improves image quality, Reduces spot size.Applications: Beam expanding, Beam focusing in telescopes, collimators, condenser systems, Optical transceivers, Camera Systems, Imaging Systems, Optical View Finder, Laser Measurement Systems, Projection Optics Systems.Description:One side of meniscus lens is convex, another side is concave. It can be a convergent lens or a divergent lens, which is decided together by refractive index, curvature and radius.Positive or negative focal length lenses have different radii or curvature on both sides whereas neutral meniscus lenses do not focus light. Meniscus lenses are used in applications, where distortion of the beam has to be reduced. They are used for focusing beams in telescopes, collimators or condenser systems, optical transceivers or other devices.Positive meniscus lenses is convex-concave lens thicker at the center than at the edges. They are used to minimize spherical aberration. When used in combination with another lens, it’s will shorten the focal length, and increase the NA of system.Negative meniscus lenses is convex-concave lens thinner at the center than edges. They  increase the divergence of the beam without introducing any significant spherical aberration. When used in combination with another lens, they will increase the focal length, and decrease the NA of the system.Specification:Material: BK7, Fused Silica, SF10, CaF2, Sapphire. etc.Paraxial Focal Length Tolerance: ±2%Dimension Tolerance: ±0.2(General). ±0.05(High Precision)Centration: <3 arc minIRR: λ/4@633nm（General),λ/10@633nm(High Precision)Clear Aperture: >80%(Small Size), >95%(Laege Size)Surface Figure: <1.5λ@633nm（General),<λ/4@633nm(High Precision)Surface Quality: 60/40（General),10/5(High Precision)Bevel: <0.25mmCoating: Uncaoted, AR,PR, HR, etc.