optical cylindrical BK7 Meniscus
Meniscus lens are available in either positive or negative. Positive Meniscus Lenses may be used to increase the numerical aperture of a positive lens assembly, without an undue increase in the aberrations. Negetive Meniscus Lenses are the best lens form where one conjugates is relatively far from the lens or where both conjugates are the same size of the lens.
Technical Parameters
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1
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Material
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BK7,Fused silica,Sapphire,CaF2,Znse,other optical glass is available
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2
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Dimension tolerance
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+0.0/-0.15mm (General), +0.0/-0.02mm (High Precision)
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3
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Focal length tolerance
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+/-2%
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4
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Centration
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<3arc min
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5
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Clear aperture
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>80% (Small Size), >95% (Large Size)
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6
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Surface figure
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lambda/2 (General), lambda/4 (High Precision)
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7
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Surface Quality
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10/5,20/10,40/20,60/40,80/50
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8
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Protective bevel
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<0.2mm*45degree
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9
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Coating
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Uncoated,HR,AR,PR,BBAR,upon customer 's request
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Features：
High Precision Dimension Control, Optional Substrate Material,Minimizes spherical aberration, Improves image quality, Reduces spot size.
Applications：
Beam expanding, Beam focusing in telescopes, collimators or 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.
Spherical Lens 