47-655-INK 9 mm Dia. N-BK7/N-SF5 Achromatic Doublet; EFL=36mm VIS 0° 425-675nm

The 47-655-INK is a high-quality achromatic doublet lens, sourced from Edmund Optics, designed with a 9 mm diameter and a focal length of 36 mm. This lens is specifically engineered for the visible spectrum, covering wavelengths from 425 to 675 nm, making it ideal for a wide range of applications that require excellent chromatic correction and high-resolution imaging.

The lens is constructed from two types of glass, N-BK7 and N-SF5, both from Schott, ensuring superior optical performance. The N-BK7, a borosilicate crown glass, is known for its excellent homogeneity, low dispersion, and high transmittance in the visible spectrum. The N-SF5, a dense flint glass, offers high refractive index and Abbe number, making it ideal for achromatic applications.

The lens features a standard curvature coating on both the front and back surfaces, specifically the EDM VIS-0 STD curve. This coating enhances the lens's overall light transmission and reduces surface reflections, thereby improving image quality and contrast.

The geometry of the lens includes a thickness of 3.32 mm at the edge, a center thickness of 2.5 mm, and a center thickness 'a' of 1.5 mm. The lens's inner and outer radii are 0 mm, and the radii of curvature are 22.16 mm for the first surface and -15.98 mm and -46.14 mm for the second and third surfaces, respectively.