This is the G063162331, a 31.5 mm diameter UVFS mounted double-convex lens with an effective focal length (EFL) of 40mm. The lens is sourced from Qioptiq Photonics, a renowned vendor in the field of precision optics.
The lens is of the spherical type, specifically a symmetric convex-convex lens. It has a base shape of a circle, with a thickness of 2mm at the edge and 8.6mm at the center. The lens's inner and outer radii are both zero, while the first and second radii are 39.243mm and -39.243mm respectively.
The lens is made from UVFS material with a Mal-1965 ID. It is designed to work with a wavelength of 355nm. The lens's coating is Qio AL RALVIS AOI 45 on both the front and back sides.
The lens is currently in stock and can be purchased directly from the Qioptiq Photonics website using the provided weblink.