This is a 25mm diameter, 25mm focal length double-convex lens, specifically designed for use in the near-infrared (NIR) spectrum. The lens is sourced from Edmund Optics and is currently in stock. It is made from n-SF5 Schott, a material known for its excellent optical properties in the NIR range.
The lens features a standard curve coating on both the front and back surfaces, specifically the EDM NIR-II STD curve. This coating is designed to optimize performance in the NIR II spectrum, which spans from 750nm to 1550nm.
The lens has a center thickness of 8mm and an edge thickness of 2.9mm. The effective focal length (EFL) is 25mm, and the back focal length (BFL) is 22.47mm. The first and second radii of curvature are 31.94mm and -31.94mm, respectively. The lens has no inner or outer radius, indicating a uniform curvature.