This is a Plano-Convex Lens, a type of spherical lens, sourced from Edmund Optics. It is designed with a base shape of a circle and has a diameter of 20.0mm. The lens has a thickness of 1.13mm at the edge and 2.35mm at the center. The effective focal length (EFL) of this lens is 80.0mm, and the radius of curvature (R1) is 41.48mm. The back focal length (BFL) is 78.45mm, and the inner and outer radii are both 0mm.
The lens is made of n-BK7 Schott, a popular optical glass due to its excellent optical properties and relatively low cost. It is designed to work with a wavelength of 1550nm. The lens features a front and back coating of EDM Las V-Coat 1550, a type of anti-reflective coating that is specifically designed for use with lasers at this wavelength. This coating helps to reduce surface reflections, improving the efficiency and performance of the lens.