49-368 25 mm Dia. N-BK7/N-SF5 Achromatic Doublet; EFL=300mm VIS-NIR 400-1000nm

The 49-368 is a high-quality achromatic doublet lens, designed and manufactured by Edmund Optics. This lens, with a 25 mm diameter, is specifically engineered for use in the visible (VIS) and near-infrared (NIR) spectrum, spanning from 400 to 1000 nanometers.

The lens is constructed from two types of glass, N-BK7 and N-SF5, both from Schott, ensuring high-quality imaging and minimal chromatic aberration. The N-BK7, a borosilicate crown glass, is known for its excellent optical transmission and low dispersion, making it ideal for use in achromatic doublets. The N-SF5, a dense flint glass, further reduces chromatic aberration and provides excellent image sharpness.

The lens features an effective focal length (EFL) of 300mm, making it suitable for a wide range of optical applications. The geometry of the lens includes a thickness of 4.88mm at the edge, a center thickness of 3mm, and a center thickness 'a' of 2.5mm. The lens also features an inner radius of 0 and an outer radius of 0, indicating a symmetrical design.

The 49-368 is coated with Edmund Optics' VIS-NIR coating (edm visnir0sp2002000) on both the front and back surfaces. This coating enhances the lens's transmission in the VIS and NIR ranges, reduces surface reflections, and increases overall system efficiency.