This is the G052310331 model from Qioptiq Photonics, a 12.7 mm diameter Plano-Concave Lens made of N-BK7 glass. The lens is mounted and has a focal length (EFL) of -200mm, indicating its diverging nature.
The lens's geometry is characterized by a 12.7 mm diameter, a 1.5 mm thickness at the center, and a -102.92 mm radius of curvature (R1). The lens's inner and outer radii are both zero, suggesting a simple plano-concave design.
The lens is made of N-BK7 glass, a common material in optical applications due to its excellent optical properties. It is designed for use at a wavelength of 588 nm.
The lens features a front and back coating of Qio AL RALVIS AOI 45. This coating is designed to enhance the lens's performance by reducing reflection and improving transmission.