AL72550-E3 25.4 mm Dia. ZnSe AR coated Aspheric Lenses; EFL=50mm; NA=0.22 7-12µm

The AL72550-E3 is a high-quality aspheric lens offered by Thorlabs, designed for use in the 7-12 µm wavelength range. This lens is made from ZnSe (Zinc Selenide) material, specifically the ZnSe CONNOLLY variant, which is known for its excellent optical properties in the infrared spectrum.

The lens has a diameter of 25.4 mm and an effective focal length (EFL) of 50 mm, making it suitable for a wide range of optical applications. The aspheric design of the lens helps to reduce spherical aberration, which is particularly beneficial when dealing with high numerical aperture (NA) systems. The NA of this lens is 0.22, further enhancing its performance in such systems.

The lens features a front and back coating of THo E3 BBAR 8 AOI, which stands for Thorlabs' Enhanced 3-layer Broadband Anti-Reflection coating with 8° angle of incidence. This coating is designed to reduce surface reflections and increase transmission, thereby improving the overall efficiency of the optical system.

The lens has a thickness of 3.9 mm at the edge and 5 mm at the center. The inner and outer radii are not specified, indicating that they are not critical parameters for this particular lens design.

In terms of availability, the AL72550-E3 is currently in stock, according to Thorlabs' website. For more detailed information, users are encouraged to visit the product page at https://www.thorlabs.com/thorproduct.cfm?partnumber=AL72550-E3.