A220-A 7.2 mm Dia. D-K59 Molded Glass Aspheric Lenses; EFL=11 mm; NA=0.26 AR 350-700nm

The A220-A is a high-quality aspheric lens, precision-molded from D-K59 glass, a type of glass known for its excellent optical properties. This lens boasts a diameter of 7.2 mm and an effective focal length (EFL) of 11 mm, making it suitable for a wide range of optical applications. The lens has a numerical aperture (NA) of 0.26, which contributes to its high light-gathering capability and excellent image resolution.

The lens features an anti-reflection (AR) coating that spans the wavelength range of 350-700nm. This coating reduces surface reflections, thereby improving transmission and enhancing the overall performance of the lens. The A220-A is designed to be used in applications that require a high level of optical precision and clarity.

The lens's geometry is defined by its inner and outer radii, both of which are 0 in this case. The thickness at the edge is 3.82 mm, while the center thickness is 5 mm. The lens's front and back surfaces have aspheric shapes, with the front surface having a conic constant of 0 and the back surface having a conic constant of -5.97. The lens's front surface also has a series of aspheric coefficients (a2 to a16), all of which are 0, indicating a perfect spherical shape. The back surface, on the other hand, has non-zero aspheric coefficients, indicating a more complex shape designed to correct spherical aberration and other optical aberrations.