The 45-221 is a high-quality negative achromatic doublet lens, sourced from the renowned optical vendor, Edmund Optics. This lens, with a diameter of 25 mm, is designed for use in the visible spectrum, specifically between 400-700nm. The lens features a focal length of -50mm, making it suitable for a wide range of optical applications.
The lens is composed of two elements, N-BAF10 and N-SF10, both from Schott. These materials are known for their excellent optical properties, contributing to the lens's high performance. The lens is coated with Edmund Optics' standard MgF2 coating on both the front and back surfaces, which enhances its transmission capabilities and overall durability.
The geometry of the lens is carefully designed to optimize its optical performance. The lens has an edge thickness of 9.06mm, with the inner and outer radii being 0mm. The center thickness is 2.5mm, while the center thickness 'a' is 4.06mm. The lens's shape is a multiplet, which is a combination of multiple simple lenses to achieve superior optical performance.