63-725 40 mm Dia. N-BK7/N-SF5 Achromatic Doublet; EFL=100mm VIS-NIR 400-1000nm

The 63-725 is a high-quality achromatic doublet lens, designed and manufactured by Edmund Optics. This lens, with a diameter of 40 mm, is specifically engineered for use in the visible (VIS) and near-infrared (NIR) spectrum, spanning from 400 to 1000 nm. The lens is part of Edmund Optics' extensive catalog, and it is available for purchase directly from their website.

The lens is a multiplet, meaning it is composed of multiple optical elements. In this case, it is made from two types of glass: N-BK7 and N-SF5, both from Schott. This combination helps to correct chromatic aberration, a common issue in lenses where different wavelengths of light are focused at different points. By using an achromatic doublet, the 63-725 lens provides sharper, clearer images across the entire spectrum it covers.

The lens has an effective focal length (EFL) of 100 mm, which is the distance from the lens's optical center to the point where the light rays converge. This EFL makes the lens suitable for a wide range of applications, including imaging, metrology, and spectroscopy.

The lens's geometry is also noteworthy. It has a thickness of 7.92 mm at the edge, with no inner or outer radius specified, indicating that the lens is a simple, flat-surfaced design. The center thickness is 10 mm, with an additional 3 mm of material (referred to as 'thickness center a') added for structural support or other considerations.

The 63-725 lens is coated with Edmund Optics' VIS-NIR coating (edm visnir0sp2002000), which is applied to both the front and back surfaces. This coating is designed to enhance the lens's performance in the VIS and NIR ranges, improving transmission and reducing reflection.