Plano Concave Lens

A planar concave lens is a type of lens with a negative focal length, featuring one flat surface and one concave surface. It is typically used to diverge light beams. The lens is thinner in the middle than at the edges, causing light rays to diverge as they pass through, rather than converging as they would with a convex lens.

Features of Plano Concave Lens

The main characteristic of a plano-concave lens is its negative focal length, which makes it primarily used for beam collimation, increasing or decreasing focal length, and expanding or reducing images. To minimize spherical aberration, coma, and astigmatism, plano-concave lenses are often employed in high-energy laser systems to reduce the likelihood of residual reflected light converging from the surface.

Plano concave lens is used for beam expansion, projection, and increasing the focal length of optical systems. Depending on specific requirements, plano-concave lenses can be provided with or without anti-reflective coatings, making them suitable for visible light, near-infrared light, and specific wavelength applications. For example, fused silica is suitable for ultraviolet applications, while single-crystal calcium fluoride is ideal for certain wavelength applications.