45-419 75 mm Dia. N-BK7/N-SF5 Achromatic Doublet; EFL=400mm MgF2 400-700nm

The 45-419 is a high-quality achromatic doublet lens, boasting a 75 mm diameter and a focal length of 400mm. This lens is sourced from the renowned optical vendor, Edmund Optics, and is available for purchase on their official website. The product link provided is valid and indicates that the item is currently in stock.

The lens is constructed from two types of glass, N-BK7 and N-SF5, both from Schott. This combination is used to correct chromatic aberration, a common issue in optical systems where different wavelengths of light are focused at different points. The achromatic design ensures that the lens focuses both red and blue light at the same point, providing sharper images.

The lens has a standard MgF2 coating on both the front and back surfaces. This coating is designed to reduce reflection and increase transmission in the 400-700nm range, making it ideal for use in a wide range of applications.

The geometry of the lens is carefully designed to optimize its performance. The edge thickness is 12.84mm, while the center thickness is 11.05mm. The lens features three radii of curvature: r1 is 246.5mm, r2 is -180.92mm, and r3 is -526.7mm. These parameters, along with the lens's diameter and focal length, contribute to its overall optical power and performance.