AL2550M-B 25 mm Dia. N-BK7 High-Precision; CNC Polished Aspheric Lenses; EFL=50 mm; NA=0.23 AR 650-1050nm

The AL2550M-B is a high-precision asperic lens offered by Thorlabs, a leading vendor in the optical industry. This lens, with a diameter of 25 mm, is crafted from N-BK7, a renowned glass type from Schott, ensuring high-quality optical performance.

The lens features an effective focal length (EFL) of 50 mm, making it suitable for a wide range of optical applications. The asphere design, combined with CNC polishing, ensures high-precision and low spherical aberration, enhancing the overall image quality.

The lens has a numerical aperture (NA) of 0.23, which is a measure of the light-gathering ability of the lens. A higher NA allows for a wider angle of acceptance and thus more light can be collected, which is beneficial for applications requiring high light throughput or resolution.

The lens is coated with a broadband anti-reflection (AR) coating, specifically designed for the 650-1050nm wavelength range. This coating reduces surface reflections, thereby increasing transmission and minimizing ghost images and flare.

The lens has a thickness of 3 mm at the edge and 6 mm at the center, providing structural rigidity. The lens is in stock and available for immediate shipping, as indicated by the valid weblink status.