title: Tunable-focus flat liquid-crystal diffractive lens.
abstract: We demonstrate an innovative variable-focus flat liquid-crystal diffractive lens (LCDL) with 95% diffraction efficiency and millisecond switching times using a +/-2.4 V ac input. This lens is based on the electrical modulation of a 3 mum layer of nematic liquid-crystal sandwiched between a Fresnel zone electrode structure and a reference substrate. Each zone is divided into 12 subzones to digitize the phase profiles and define the phase wrapping points. The focusing power can rapidly be switched by electrically changing the number of subzones and re-establishing the wrapping points. Potential applications include zooms with no moving parts and autofocus lenses for compact imaging devices.
authors.affiliation: College of Optical Sciences, University of Arizona Tucson, Arizona 85721, USA. pouria@u.arizona.edu
authors.forename: Pouria
authors.initials: P
authors.lastname: Valley
authors.forename: David L
authors.initials: DL
authors.lastname: Mathine
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Dodge
authors.forename: Jim
authors.initials: J
authors.lastname: Schwiegerling
authors.forename: Gholam
authors.initials: G
authors.lastname: Peyman
authors.forename: N
authors.initials: N
authors.lastname: Peyghambarian