LB1247-B N-BK7 Bi-Convex Lens; Dia:2 in; f=750.0 mm ARC 650-1050nm

The LB1247-B is a high-quality bi-convex lens from Thorlabs, designed with a diameter of 2 inches and a focal length of 750.mm. This lens is fabricated from N-BK7, a popular glass type in the optical industry, known for its excellent optical properties and versatility. The lens features a double-convex shape, which provides a superior optical performance by minimizing spherical aberration.

The lens has a clear aperture of 50.8mm, with a thickness of 3mm at the edge and 3.8mm at the center. The effective focal length (EFL) is 750mm, while the back focal length (BFL) is 748.7mm. The radii of curvature for the first and second surfaces are 772mm and -772mm, respectively. The lens does not have any inner or outer radius specified, indicating a uniform curvature across the surfaces.

The LB1247-B lens is coated with Thorlabs' BBAR coating (Broadband Anti-Reflection) on both the front and back surfaces. This coating enhances the lens's performance by reducing surface reflections and increasing transmission across the 650-1050nm spectral range. The coating ensures optimal light transmission, making this lens suitable for various applications, including imaging, beam shaping, and laser systems.