AC254-250-C 25.4 mm Dia. N-SF2/N-SF6 Unmounted Achromatic Doublet; EFL=249.2mm 1050-1700nm

The AC254-250-C is a high-quality achromatic doublet lens, sourced from the renowned optical component manufacturer, Thorlabs. This lens is specifically designed for use in the infrared spectrum, with a broad wavelength range of 1050-1700nm, making it an ideal choice for a wide range of applications in this spectral region.

The lens features a circular geometry with a diameter of 25.4mm and a thickness of 6mm at the edge. The inner and outer radii are 0mm, indicating a flat profile. The lens's base shape is also circular, with three radii (r1, r2, and r3) of 44mm, -57.7mm, and 93.1mm, respectively, and two central thicknesses of 4.5mm and 2.5mm. These specifications suggest a complex lens design that provides superior optical performance.

The lens is made from two types of Schott glass, n-SF2 and n-SF6, which are known for their excellent optical properties in the infrared spectrum. Both the front and back surfaces of the lens are coated with Thorlabs' proprietary AR coating (tho ac1050-1700-c), designed to reduce surface reflections and increase transmission in the 1050-1700nm range.

The lens is unmounted, providing users with the flexibility to integrate it into their optical systems in the most suitable way. The lens's shape is classified as a multiplet, indicating a compound lens design that offers superior optical performance compared to a single element lens.