68-254 25mm Dia. Germanium Infrared Aspheric Lens; EFL=25mm; NA=0.5 BBAR 8-12µm

This is a high-quality 25mm diameter germanium aspheric lens, catalog number 68-254, available from the renowned optical components vendor, Edmund Optics. The lens is specifically designed for infrared applications, with a wavelength range of 4000nm. It features a broadband anti-reflection coating (BBAR) optimized for the 8-12µm range, which enhances its performance in infrared spectrum applications.

The lens has an effective focal length (EFL) of 25mm, providing a compact and efficient optical solution. Its numerical aperture (NA) is 0.5, indicating a wide acceptance angle and high light-gathering capability. The lens's geometry includes an inner radius of 0mm, an outer radius of 0mm, a thickness at the edge of 2.32mm, and a thickness at the center of 3.45mm. The front and back surfaces of the lens are aspheric, with radii of curvature of 26.93mm and 37.8mm, respectively.

The lens's coating is a specialized AR coating, specifically designed for germanium in the 8-12µm range. This coating, named 'edm arcedgermanium81', ensures high transmission and low reflectance across the specified wavelength range. The lens is available for purchase through the Edmund Optics website, and the link provided is valid and indicates that the lens is in stock.