The 49-350 is a high-quality achromatic doublet lens, boasting a 20 mm diameter and an effective focal length of 40mm, specifically designed for the visible to near-infrared spectrum (400-1000nm). This lens is sourced from the reputable optical vendor, Edmund Optics, and is available for purchase on their official website.
The lens is constructed from two types of Schott glass, N-BAF10 and N-SF10, which are renowned for their excellent optical properties. The lens features a multilayer anti-reflection coating, specifically the EDM VIS-NIR 0SP2002000 coating, on both the front and back surfaces. This coating enhances the lens's performance by reducing surface reflections, thereby increasing transmission and minimizing lens flare and ghosting.
The lens geometry is meticulously designed, with an edge thickness of 7.83mm and a center thickness of 8mm. The lens also features a central thickness 'a' of 2mm, which provides additional design flexibility. The radii of curvature for the three surfaces are R1=27.63mm, R2=-17.58mm, and R3=-171.25mm. These parameters contribute to the lens's excellent imaging performance and chromatic correction.