A zoom lens is an optical imaging system that changes its magnification or focal length while keeping the relative location of the image plane stationary. A mechanical zoom lens can have a number of optical elements (e.g., lenses) and use cams or gears to adjust the spacing between the number of elements to vary the optical magnification. Adjusting the spacing between the number of elements can require sub-millimeter precision that has the potential of malfunctioning.
USPTO Backgrounds
USPTO Backgrounds