AC508-180-A 50.8 mm Dia. N-BK7/N-SF5 Unmounted Achromatic Doublet; EFL=180mm 400-700nm

The AC508-180-A is a high-quality achromatic doublet lens, unmounted and with a diameter of 50.8 mm, sourced from the renowned optical components manufacturer, Thorlabs. This lens is designed for use within the spectral range of 400-700nm, making it suitable for a wide range of applications within the visible light spectrum.

The lens features a focal length of 180mm, indicated by the 'EFL' parameter in its name. This long focal length allows for tight beam convergence or high magnification, depending on the application. The lens is constructed from two types of glass, N-BK7 and N-SF5, both from Schott's extensive catalog. These materials were chosen for their excellent optical properties and ability to minimize chromatic aberration, a common issue in lens systems.

The lens geometry is characterized by its base shape, which is circular, and its various radii and thicknesses. The edge thickness is 9.4mm, while the center thicknesses are 12mm and 2mm for the first and second surfaces, respectively. The lens's inner and outer radii are both zero, and the first and second radii of curvature are 109.7mm and -80.7mm, respectively. The third radius of curvature is -238.5mm, indicating a complex lens design that has been optimized for performance.

The lens is coated with Thorlabs' proprietary anti-reflection coating, AC400-700-A, on both the front and back surfaces. This coating is designed to reduce surface reflections and increase transmission within the specified spectral range, further enhancing the lens's performance.