49-946 20 mm Dia. N-BK7/N-SF5 Achromatic Doublet; EFL=80mm VIS 0° 425-675nm

The 49-946 is a high-quality achromatic doublet lens, sourced from the renowned optical components manufacturer, Edmund Optics. This lens boasts a 20 mm diameter and an effective focal length (EFL) of 80 mm, specifically designed for the visible light spectrum ranging from 425 to 675 nm.

The lens is meticulously crafted from two types of Schott glass: N-BK7 and N-SF5. These materials are chosen for their excellent optical properties, contributing to the lens's high performance. The N-BK7, a borosilicate crown glass, is known for its low dispersion and high homogeneity, making it an ideal choice for optical systems that demand high image quality. On the other hand, N-SF5, a dense flint glass, offers high refractive index and Abbe number, which aids in the correction of chromatic aberrations.

The 49-946 lens features a sophisticated geometry, with a center thickness of 4 mm, edge thickness of 4.51 mm, and radii of curvature of 50.49 mm and -37.06 mm for the first and second surfaces, respectively. The third surface, with a radius of curvature of -102.19 mm, is designed to further enhance the lens's achromatic properties.

The lens is coated with Edmund Optics' standard anti-reflection coating, specifically designed for the visible light spectrum (VIS 0°). This coating reduces surface reflections, thereby increasing transmission and improving overall system performance.