This is the G311208331 model from Qioptiq Photonics, a 22.4 mm diameter UVFS Double-Convex Lens with an effective focal length (EFL) of 40mm. The lens is sourced from Qioptiq Photonics, a renowned vendor in the optical industry, and is available for purchase on their website, where it is currently in stock.
The lens is a Spherical Lens of the Sub Type Symmetric-Convex, featuring a Base Shape of Circular. Its geometry includes a thickness edge of 1.7mm and a thickness center of 4.9mm. The lens is made from UVFS material with the ID mal- 1965.
The G311208331 model is designed for use with a wavelength of 355nm. It comes with a coating on both the front and back, specifically Qio AL RALVIS AOI 45. This coating enhances the lens's performance and durability, making it suitable for various applications.