45-214 25 mm Dia. N-BK7/N-SF5 Achromatic Doublet; EFL=225mm MgF2 400-700nm

The 45-214 is a high-quality achromatic doublet lens, boasting a 25 mm diameter and a focal length of 225 mm. 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 currently active and indicates that the lens is 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 features a standard MgF2 coating on both the front and back surfaces. This coating is designed to reduce reflection and increase transmission in the 400-700 nm spectral range. The coating also helps to protect the lens from environmental damage and scratching.

The geometry of the lens is carefully designed to optimize its performance. The edge thickness is 4.67 mm, while the center thickness is 3 mm. The lens also features a central thickness of 2.5 mm at the apex, which is the point of maximum curvature. The inner and outer radii of the lens are 0, indicating a symmetrical design.