49-318 9 mm Dia. N-BK7/N-SF5 Achromatic Doublet; EFL=45mm VIS-NIR 400-1000nm

The 49-318 is a high-quality achromatic doublet lens, sourced from the renowned optical vendor, Edmund Optics. This lens is specifically designed for use within the visible to near-infrared spectrum, spanning from 400 to 1000nm. The lens boasts a 9mm diameter and a focal length of 45mm, making it a versatile choice for a wide range of optical applications.

The lens is constructed from two types of glass, N-BK7 and N-SF5, both from Schott. This combination is used to minimize chromatic aberration, a common issue in optical systems where different wavelengths of light are focused at different points. By using these materials, the 49-318 achieves superior image quality and color correction.

The lens geometry is intricately designed, with a central thickness of 3mm and edge thickness of 3.76mm. The first and second radii of curvature are 27.83mm and -19.75mm respectively, while the third radius of curvature is -57.06mm. This complex design allows for precise control over the light path, enhancing the performance of the lens.

The lens is coated with Edmund Optics' VIS-NIR coating (edm visnir0sp2002000) on both the front and back surfaces. This coating is designed to reduce surface reflections and increase transmission, further improving the overall performance of the lens.