The 47-692 is a high-quality achromatic doublet lens, boasting a 6.25 mm diameter and an effective focal length (EFL) of 20 mm, specifically designed for the visible light spectrum ranging from 425 to 675 nm. This lens is sourced from the reputable optical vendor, Edmund Optics, and is available for purchase through their website.
The lens is constructed from two types of glass, N-BK7 and N-SF5, both from Schott, ensuring excellent optical performance. The front and back surfaces of the lens are coated with the EDM VIS-0 standard curve coating, providing improved light transmission and protection against environmental factors.
The lens geometry is carefully designed with a 3 mm thickness at the edge, a 2.7 mm thickness at the center, and a 0.9 mm thickness at the center a. The lens features three radii of curvature: r1 at 12.3 mm, r2 at -8.71 mm, and r3 at -24.98 mm. The inner and outer radii are both 0 mm.
This achromatic doublet lens is a multiplet, meaning it is composed of multiple optical elements. This design helps to correct chromatic aberration, a common issue in lens systems, providing clear and focused images. The lens is available in a circular shape, making it suitable for a wide range of optical applications.