This is a mounted plano-concave lens, type G052307331, manufactured by Qioptiq Photonics. The lens has a diameter of 12.7 mm and a center thickness of 1.5 mm. The effective focal length (EFL) of this lens is -30mm, indicating that it is a diverging lens.
The lens is made of N-BK7, a popular optical glass type known for its excellent optical properties and versatility. The curvature of the lens is spherical, with a radius of curvature (R1) of -15.51mm for the concave surface. The lens does not have an inner or outer radius, indicating that it is a simple plano-concave lens.
The lens is designed for use at a wavelength of 588nm. It comes with a coating on both the front and back surfaces. The coating is Qio AR Al RALVIS AOI 45, which is a broadband anti-reflection coating designed to reduce surface reflections and improve transmission.
This lens is available for purchase from the Qioptiq Photonics website, where it is listed as in stock. The provided weblink leads directly to the product page for easy access.