This is the 68-247 model from Edmund Optics, a 25mm diameter Germanium Aspheric Lens with an effective focal length of 30mm and a numerical aperture of 0.42. The lens is coated with BBAR 3-5µm, ensuring high-quality performance in the infrared spectrum.
The lens is designed with a base shape of a circle, featuring an inner radius of 0 and an outer radius of 0. The lens's thickness at the edge is 2.29mm, while its center thickness is 3.25mm. The first radius of curvature (r1) is 29.46mm, and the second radius of curvature (r2) is 40mm. The back focal length (bfl) is 27.52mm.
The lens's front and back are coated with "edm arcedgermanium35", providing excellent durability and performance. The lens's shape is aspheric, which helps to reduce spherical aberration and improve optical performance.
The lens is currently in stock and can be purchased directly from the Edmund Optics website using the provided weblink. The link has been verified and is valid as of the last update.