This is a UV-AR coated, double-convex lens, model number 46-291, available from Edmund Optics. The lens has a diameter of 18mm and a focal length of 40mm, making it suitable for a variety of applications. The base shape is circular, and the lens is spherical in geometry.
The lens has a center thickness of 4.29mm and an edge thickness of 2mm. The effective focal length (EFL) is 40mm, and the radii of curvature are 35.99mm for both the front and back surfaces. The back focal length (BFL) is 38.5mm, and the inner and outer radii are both 0mm.
The lens is made from fused silica, identified as mal-1965 in the material database. It is designed to operate at a wavelength of 587.6nm. The lens features UV-AR coatings on both the front and back surfaces, following the standard curve as specified by Edmund Optics.