title: Optically controllable and focus-tunable Fresnel lens in azo-dye-doped liquid crystals using a Sagnac interferometer.
abstract: This study demonstrates a tunable Fresnel lens in an azo-dye-doped liquid crystal (ADDLC) film using an interference technique. One Fresnel-patterned green beam using a Sagnac interferometer irradiated the UV-illuminated ADDLC cell, yielding a concentric zone plate distribution with homeotropic and isotropic structures in bright and dark regions of the green interference pattern. The proposed Fresnel lens is polarization independent, focus tunable, and the focusing efficiency of the device can be optically controlled.
authors.affiliation: Graduate Institute of Electro-Optical Engineering, National Kaohsiung First University of Science and Technology, Kaohsiung 811, Taiwan. hcyeh@nkfust.edu.tw
authors.forename: Hui-Chen
authors.initials: HC
authors.lastname: Yeh
authors.forename: Yi-Chieh
authors.initials: YC
authors.lastname: Kuo
authors.forename: Shih-Hung
authors.initials: SH
authors.lastname: Lin
authors.forename: Jia-De
authors.initials: JD
authors.lastname: Lin
authors.forename: Ting-Shan
authors.initials: TS
authors.lastname: Mo
authors.forename: Shuan-Yu
authors.initials: SY
authors.lastname: Huang
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D004396:Coloring Agents / Q000737:chemistry*; D007368:Interferometry / Q000295:instrumentation*; D007909:Lenses; D050866:Liquid Crystals / Q000737:chemistry*; D055620:Optical Phenomena
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents