354220-A 7.2 mm Dia. D-ZK3 Molded Glass Aspheric Lenses; EFL=11 mm; NA=0.25 AR 350-700nm

The 354220-A is a high-quality aspheric lens from Thorlabs, designed with a 7.2 mm diameter and a molded D-ZK3 glass material. This lens is specifically engineered for use in the 633 nm wavelength range, offering exceptional performance and precision. The lens features an effective focal length (EFL) of 11 mm and a numerical aperture (NA) of 0.25, making it suitable for a wide range of optical applications.

The lens's geometry includes an inner radius of 0 and an outer radius of 0, with a thickness at the edge of 4.212 mm and a thickness at the center of 5.032 mm. The front and back surfaces of the lens are coated with a broadband anti-reflection coating (AR), optimized for the 350-700 nm range. This coating helps to minimize surface reflections, thereby improving transmission and overall system efficiency.

The lens's aspheric design helps to reduce spherical aberration, a common issue in traditional spherical lenses. This results in improved image quality and increased light gathering capability. The lens's shape is defined by its front and back radii (r1 and r2), as well as its conic constant (k1) and aspheric coefficients (a2 to a16). These parameters are carefully controlled during the manufacturing process to ensure the lens meets the specified optical performance.