meniscus lens

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Meniscus Lens

Meniscus lens is divided into positive and negative lunar lenses.One side of a meniscus lens is convex and the other side is concave. It can be a convergent lens or a divergent lens, determined by the refractive index, curvature, and radius together. Widely used in photography systems, projection systems, imaging systems, optical viewfinder, and laser measurement systems.

Types of Meniscus Lenes

Positive Meniscus Lens:

This lens is used in applications requiring a short focal length (typically less than 2.5). For focal lengths between 2.5 and 10, positive meniscus lenses are ideal for reducing spot size and improving image quality. In this type, the concave surface has a smaller curvature (less steep), and the convex surface has a larger curvature (more steeply curved).

Negative Meniscus Lens:

These lenses are suitable for use with high-refractive-index infrared materials. They serve as an alternative to conventional negative lenses with steep concave surfaces and shallow convex curves. Negative meniscus lenses are commonly used in beam expansion systems where minimizing spherical aberration is critical.