SLB-50.8-90N 50.8 mm Dia. x -90.0 mm FL; Plano-Concave Lens Uncoated

The SLB-50.8-90N is a Plano-Concave Lens with a diameter of 50.8 mm and a focal length of -90.0 mm, making it a negatively powered lens. This lens is sourced from OptoSigma, a renowned vendor in the optical industry, and is uncoated. The lens is made of n-BK7 Schott, a popular optical glass due to its excellent optical properties and high Abbe number.

The lens's geometry includes a thickness edge of 10.5 mm and a thickness center of 3 mm, providing a robust structure. The inner and outer radii are both 0 mm, indicating a flat surface on one side and a concave surface on the other. The back focal length (BFL) is -92 mm, slightly longer than the focal length, which is typical for Plano-Concave lenses.

This lens is designed for use at a single wavelength of 546.1 nm, making it suitable for monochromatic applications. The shape of the lens is spherical, which is the most common shape for optical lenses due to its ease of manufacturing and good optical performance.

Please note that the lens is uncoated, which means it does not have any anti-reflective or protective coatings. This may result in unwanted reflections and could make the lens more susceptible to damage. However, uncoated lenses are often chosen for their lower cost and simplicity.