US Patent 7031071 Optical device

An optical apparatus includes an optical system for performing variable power by one lens group or integrated lens groups; a variable optical-characteristic element; a drive circuit for driving the variable optical-characteristic element; and a picture element, wherein the apparatus is constructed by providing a predetermined resolution chart with a known distance, feeding drive information to the variable optical-characteristic element in accordance with the distance, photographing images of the resolution chart, and adjusting and fixing the position of the picture element so as to substantially maximize the contrast of the images.