The 47-736-INK is a high-quality achromatic doublet lens, boasting a 20 mm diameter and an effective focal length (EFL) of 60 mm, specifically designed for the visible spectrum between 425-675 nm. This lens is sourced from Edmund Optics, a renowned vendor known for their exceptional optical components.
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 low dispersion and excellent homogeneity, while the N-SF5, a fluorite crown glass, offers a low refractive index and low dispersion. This combination effectively minimizes chromatic aberration, a common issue in optical systems.
The lens features a standard anti-reflection coating on both the front and back surfaces, specifically the EDM VIS-0 STD CURVE coating. This coating enhances light transmission, reduces surface reflections, and increases the overall efficiency of the optical system.
The lens geometry is meticulously designed, with a central thickness of 5 mm and edge thickness of 4.98 mm. The radii of curvature are R1 = 35.92 mm, R2 = -28.12 mm, and R3 = -83.79 mm, providing the lens with its unique optical properties.