LA1859-B N-BK7 Plano-Convex Lens; Dia:18.0 mm; f=20.0 mm ARC 650-1050nm

The LA1859-B is a high-quality plano-convex lens from Thorlabs, designed for use in a wide range of optical applications. This lens is made from N-BK7, a popular glass type known for its excellent optical properties, and is manufactured by Schott, a leading glass manufacturer.

The lens has a diameter of 18.0 mm and a focal length of 20.0 mm, making it a versatile choice for many setups. The edge thickness is 1.8 mm, while the center thickness is 7.1 mm, providing a good balance between weight and optical performance. The lens features a double-sided broadband anti-reflection coating (tho b bbar), designed to reduce surface reflections and increase transmission in the 650-1050nm spectral range.

The LA1859-B is a spherical lens, with a radius of curvature (r1) of 10.3 mm and a back focal length (bfl) of 15.3 mm. The inner and outer radii are both 0 mm, indicating a flat surface on one side of the lens.

According to the vendor's website, this item is currently in stock, making it a readily available option for those in need of a high-quality plano-convex lens. The website also provides further technical details and specifications, as well as options for customization and additional accessories.