The LB1859-A is a high-quality bi-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, particularly its high refractive index and low dispersion.
The lens features a diameter of 2 inches (50.8 mm) and a focal length of 1000.0 mm, making it a versatile choice for many setups. The thickness at the edge of the lens is 3 mm, while the thickness at the center is 3.6 mm, providing a robust and durable structure.
The effective focal length (EFL) of the lens is 1000 mm, and the back focal length (BFL) is 998.8 mm. The radii of curvature for the first and second surfaces are 1029.5 mm and -1029.5 mm, respectively. The lens has no inner or outer radius, indicating a uniform curvature across the surfaces.
The lens is coated with a broadband anti-reflection coating (ARC) that covers the wavelength range of 350-700 nm, ensuring high transmission and minimal loss of light. This coating is applied to both the front and back surfaces of the lens, further enhancing its performance.