The 89-170 is a Double-Convex Lens, a type of Spherical Lens, sourced from Edmund Optics. This lens, with a base shape of Circular, has a diameter of 20mm and a thickness of 1.88mm at the edge, while the center thickness measures 5.3mm. The effective focal length (EFL) of this lens is 30mm.
The lens's first radius of curvature (R1) is 30.08mm, and the second radius of curvature (R2) is -30.08mm, indicating its double-convex shape. The back focal length (BFL) is 28.2mm. The lens is made of n-BK7 Schott, a popular optical glass due to its excellent optical properties and relatively low cost.
The lens features VIS-EXT coating on both the front and back surfaces, designed for the visible spectrum (350-700nm). This coating enhances the lens's performance by reducing reflection and increasing transmission, thereby improving the overall system's efficiency.
Please note that the Inner and Outer Radius parameters are not specified in the provided data, indicating that these values are either not applicable or not provided by the vendor.