SLB-20-70N 20.0 mm Dia. x -70.0 mm FL; Plano-Concave Lens Uncoated

The SLB-20-70N is a Plano-Concave Lens with a 20.0 mm diameter and a focal length of -70.0 mm. This lens is sourced from OptoSigma, a renowned vendor in the optical industry. The lens is made of n-BK7 Schott material, a popular choice for its high refractive index and low dispersion, making it ideal for various optical applications.

The lens's geometry is characterized by its spherical shape, with a center thickness of 2 mm and an edge thickness of 3.4 mm. The inner and outer radii are both 0, indicating a flat surface on one side and a concave surface on the other. The back focal length (BFL) is -71.3 mm, slightly longer than the specified focal length, which is typical for Plano-Concave lenses.

This lens is uncoated, meaning it does not have any additional layers to enhance its optical properties. While this may limit its performance in certain applications, it also means that the lens is more cost-effective and versatile, making it suitable for a wide range of uses.

The lens is designed to work with a wavelength of 546.1 nm, a common choice in many optical systems. It is in stock and ready to be shipped, as indicated by the valid weblink status.