AL2520M-B 25 mm Dia. S-LAH64 High-Precision; CNC Polished Aspheric Lenses; EFL=20 mm; NA=0.54 AR 650-1050nm

The AL2520M-B is a high-precision aspheric lens offered by Thorlabs, designed with a 25 mm diameter and a focal length of 20 mm. This lens is crafted from S-LAH64, a high-quality optical glass from Ohara, ensuring excellent optical performance. The lens features a high numerical aperture (NA) of 0.54, making it suitable for applications requiring high light-gathering capabilities.

The lens's aspheric design helps minimize spherical aberration, providing superior image quality compared to traditional spherical lenses. The surface of the lens is CNC polished, ensuring exceptional smoothness and accuracy. The lens is coated with a broadband anti-reflection coating, optimized for the 650-1050 nm range, reducing surface reflections and improving transmission.

The lens has a center thickness of 7.6 mm and an edge thickness of 2.4 mm, providing robustness and durability. The detailed geometry specifications, including the radii of curvature and aspheric coefficients, are also provided, allowing for precise optical modeling and design.