The focal length of a meniscus lens may be positive or negative.Meniscus lenses are used to correct phase differences and are often used as corrective lenses. They can also be used as converters for lighting systems, and can be used to eliminate color differences by choosing the right thickness.Negative meniscus lens is a convex-concave lens thinner at the center than edges. It increases the divergence of the beam without introducing any significant spherical aberration. When used in combination with another lens, negative meniscus lens will increase the focal length and decrease the NA of the system.
Specifications:
Material:
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BK7, Fused Silica, SF10, CaF2, Sapphire. etc.
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Paraxial Focal Length Tolerance:
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±2%
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Dimension Tolerance:
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±0.2(General). ±0.05(High Precision)
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Centration:
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<3 arc min
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IRR:
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λ/4@633nm（General),λ/10@633nm(High Precision)
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Clear Aperture:
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>80%(Small Size), >95%(Laege Size)
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Surface Figure:
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<1.5λ@633nm（General),<λ/4@633nm(High Precision)
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Surface Quality:
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60/40（General),10/5(High Precision)
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Bevel:
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<0.25mm
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Coating:
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Uncaoted, AR,PR, HR, etc. |
Negative meniscus lens is a convex-concave lens thinner at the center
than edges. It increases the divergence of the beam without introducing
any significant spherical aberration. When used in combination with
another lens, negative meniscus lens will increase the focal length and
decrease the NA of the system.
Negative meniscus lenses are a common element in beam expander
applications. Negative meniscus lenses are designed to minimize
spherical aberration, which is what negative meniscus lens uses.
