The SLB-25.4B-25NM is a high-quality double-concave lens, designed and manufactured by OptoSigma. This lens, with a diameter of 25.4 mm, is specifically designed for use within the wavelength range of 400-700nm, making it suitable for a wide range of optical applications.
The lens features a base shape of a circle, with a thickness at the edge of 8.6 mm and a center thickness of 2 mm. The effective focal length (EFL) of this lens is -24.7 mm, and it has a back focal length (BFL) of -25.4 mm. The first radius of curvature (R1) is -25.95 mm, while the second radius of curvature (R2) is 25.95 mm. The inner radius is 0 mm, and the outer radius is also 0 mm.
The lens is made from n-BK7 Schott, a popular optical glass due to its excellent optical properties. It features a coating on both the front and back surfaces, specifically an opt M coating, which enhances its performance within its specified wavelength range.