This is a 2.5mm diameter, plano-convex lens with a 4.0mm focal length, 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-lasf9 Schott material, which is known for its excellent optical properties in the NIR range.
The lens features a standard curvature coating on both the front and back surfaces, specifically the EDM NIR-I STD curve. This coating is designed to enhance the lens' performance in the NIR spectrum, improving transmission and reducing unwanted reflections.
The lens has a center thickness of 0.8mm and an edge thickness of 0.56mm, providing a balance between optical performance and mechanical strength. The effective focal length (EFL) is 4mm, and the radius of curvature (R1) is 3.4mm. The back focal length (BFL) is 3.57mm, and the lens has no inner or outer radius, indicating a flat inner surface and a curved outer surface.