AS stands for Aspherical lens elements. This type of lens utilizes non-spherical surfaces on either one or both sides of the glass in order to eliminate certain types of lens aberration.
ED (Extra-Low Dispersion) Glass
An optical glass developed by Nikon that is used with normal optical glass in telephoto lenses to obtain optimum correction of chromatic aberrations.
Rear Focusing System
A system in which only the rear lens group moves during focusing, thus eliminating changes in the physical length of the lens during focusing and enabling faster focusing. Such lenses are designated with RF on the lens barrel.
Super Integrated Coating
Nikon Super Integrated Coating is Nikon's term for its multilayer coating of the optical elements in NIKKOR lenses.
Silent Wave Motor
AF-S NIKKOR lenses feature Nikon’s Silent Wave Motor (SWM), which represents a significant advance in AF lens technology. SWM uses ultrasonic vibrations—rather than a gear system—to focus the lens, providing incredibly smooth, silent and precise autofocus operation.