SLB-50.8B-100N 50.8 mm Dia. x -99.5 mm FL; Double-Concave Lens Uncoated

The SLB-50.8B-100N is a high-quality double-concave spherical lens, sourced from the reputable vendor OptoSigma. This lens, designed for use in a wide range of optical applications, boasts a diameter of 50.8 mm and a back focal length of -99.5 mm, making it a versatile choice for many setups.

The lens is made from n-bk7 Schott glass, a material known for its excellent optical properties, including a high Abbe number and low dispersion. This makes the lens ideal for applications that require high image quality and color correction, such as imaging systems, beam shaping, and laser applications.

The geometry of the lens is characterized by its concave-concave shape, with a center thickness of 3 mm and an edge thickness of 9.3 mm. The inner and outer radii are both 0, indicating a uniform curvature throughout the lens. The effective focal length (EFL) is -100.5 mm, which, combined with the back focal length, determines the lens's overall magnification and focusing capabilities.

Notably, this lens is uncoated, meaning it does not have any additional layers applied to its surface to alter its optical properties. While this may result in a slightly lower transmission rate compared to coated lenses, it can also reduce unwanted reflections and simplify the optical design.