The AF18-200mm F/3.5-6.3 XR Di-II LD Aspherical (IF) MACRO is a high power zoom lens for exclusive use with digital (APS-C size) SLR cameras. It features an optical design using XR (Extra Refractive Index) glass in an innovative way in order to optimize the overall distribution of optical power throughout the entire zoom range. This design reduces various aberrations to the absolute minimum and achieves remarkable downsizing at the same time. In addition, three hybrid aspherical lens elements and two LD (Low Dispersion) glass elements are used to accomplish effective compensation of on-axis and lateral chromatic aberrations, a critical factor to enhance the optical quality in digital photography. As a result, the lens provides outstanding optical quality in a multi-purpose zoom lens.