The 67-591 is a high-quality double-convex lens, boasting a 3mm diameter and a focal length of 4.5mm, making it an ideal choice for near-infrared (NIR) applications. This lens is sourced from the reputable vendor, Edmund Optics, and is currently in stock, ensuring quick delivery for your project needs.
The lens is crafted from n-BK7 Schott, a popular optical glass due to its excellent transparency in the visible and near-infrared regions. The base shape is circular, and the lens features a double-convex geometry, with a 1.47mm thickness at the edge and a 2mm thickness at the center. The effective focal length (EFL) is 4.5mm, and the radii of curvature are 4.29mm for the first surface and -4.29mm for the second surface. The back focal length (BFL) is 3.78mm.
The 67-591 lens is coated with Edmund Optics' NIR-II standard curve coating on both the front and back surfaces. This coating enhances the lens' performance in the NIR region, specifically between 750nm and 1550nm, making it suitable for a wide range of NIR applications.