This is the G311331322 model from Qioptiq Photonics, a 31.5 mm diameter double-convex lens made of N-SK2 Schott material. The lens features a symmetric convex-convex base shape and a circular geometry. The edge thickness is 2 mm, while the center thickness measures 9.5 mm. The effective focal length (EFL) is 30 mm, designed for use within the wavelength range of 450-700 nm.
The lens's front and back surfaces are coated with the Qio Bbar Arb2visnbk7 coating, providing enhanced performance and durability. The lens's shape is spherical, and it is unmounted, allowing users to integrate it into their custom optical systems easily. The weblink provided leads to the product page on Qioptiq's official website, where users can find more information and purchase the lens.