49-923 5 mm Dia. N-SSK8/N-SF56 Achromatic Doublet; EFL=12.5mm MgF2 400-700nm

The 49-923 is a high-quality achromatic doublet lens, sourced from the renowned optical components manufacturer, Edmund Optics. This lens, with a 5 mm diameter, is designed for use in the visible light spectrum, specifically between 400 and 700 nanometers.

The lens features a focal length of 12.5mm, indicated by the EFL (Effective Focal Length) parameter. This makes it suitable for applications that require a compact, high-performance lens. The lens is constructed from two types of glass, N-SSK8 and N-SF56, both from the Schott glass catalog. This combination is used to correct chromatic aberrations, a common issue in optical systems, thereby improving the overall image quality.

The lens's geometry is characterized by its diameter, thickness, and radii. The diameter is 5 mm, and the edge thickness is 2.78 mm. The lens's inner and outer radii are 0, indicating a planar surface. The center thickness is 2.3 mm, and the lens has an additional 1 mm thickness at the edge, providing structural rigidity.

The lens is coated with MgF2, a standard coating that offers excellent optical performance in the visible spectrum. This coating reduces reflection and increases transmission, enhancing the lens's light-gathering capability. The coating is applied to both the front and back surfaces of the lens, ensuring optimal performance from all angles.