title: Lens of electrically controllable focal length made by a glass lens and liquid-crystal layers.
abstract: A variable-focus lens is made with one or two liquid-crystal layers and a glass lens. The lens has an aperture near that of the glass lens, and its focal length is electrically changeable from that of the glass lens. The principle is described, and the lens is demonstrated experimentally.
authors.affiliation: Department of Electrical and Electronic Engineering, Akita University, 1-1 Tegatagakuen-cho, Akita 010-8502, Japan.
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
authors.forename: Mao
authors.initials: M
authors.lastname: Ye
authors.forename: Susumu
authors.initials: S
authors.lastname: Sato