This is a Plano-Concave lens, a type of spherical lens, sourced from 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 -500mm, making it a negative lens. This particular lens is designed to work within the wavelength range of 725-1050nm, which includes the near-infrared spectrum.
The lens is made of N-BK7, a type of glass commonly used in optical applications due to its excellent optical properties. The front and back surfaces of the lens are coated with qio bbar arb2nirnbk7, a coating that enhances the lens' performance by reducing reflection and increasing transmission.
The lens' geometry is such that it has a concave shape, meaning it is thicker at the edges and thinner at the center. The inner and outer radii are both zero, indicating that the lens' curvature is consistent throughout.
This lens is available for purchase on the Qioptiq Photonics website, and as of the time of data collection, it is in stock. The link to the product page is provided for your convenience.