67-333 40 mm Dia. N-BK7/N-SF5 Achromatic Doublet; EFL=750mm VIS 0° 425-675nm

The 67-333 is a high-quality achromatic doublet lens, boasting a 40 mm diameter and an effective focal length (EFL) of 750mm, specifically designed for the visible light spectrum ranging from 425 to 675nm. This lens is sourced from the renowned optical components manufacturer, Edmund Optics, and is available for purchase through their official website.

The lens is constructed from two types of glass: N-BK7 and N-SF5, both from Schott, ensuring excellent optical performance. The N-BK7 glass is a borosilicate crown glass, known for its low dispersion and high Abbe number, making it an ideal material for optical lenses. The N-SF5 glass, on the other hand, is a dense flint glass, characterized by its high refractive index and dispersion, which further enhances the lens's achromatic properties.

The lens features a sophisticated geometry, with a thickness of 7.36mm at the edge, a center thickness of 4mm, and a 0mm inner and outer radius. The curvature of the lens is defined by two radii, r1 and r2, which are 315.18mm and -506.69mm respectively. This geometry, combined with the properties of the glass, results in a lens with minimal chromatic aberration and high resolution.

The lens is coated with the EDM VIS-0 STD curve on both the front and back surfaces. This coating enhances the lens's transmission in the visible light spectrum, reduces surface reflections, and increases the overall durability of the lens.