title: Stretchable Binary Fresnel Lens for Focus Tuning.
abstract: This paper presents a tuneable binary amplitude Fresnel lens produced by wafer-level microfabrication. The Fresnel lens is fabricated by encapsulating lithographically defined vertically aligned carbon nanotube (CNT) bundles inside a polydimethyl-siloxane (PDMS) layer. The composite lens material combines the excellent optical absorption properties of the CNT with the transparency and stretchability of the PDMS. By stretching the elastomeric composite in radial direction, the lens focal length is tuned. Good focusing response is demonstrated and a large focus change (≥24%) was achieved by stretching lenses up to 11.4%.
authors.affiliation: Department of Microelectronics, Delft University of Technology, Delft, 2628 CT, The Netherlands.
authors.forename: Xueming
authors.initials: X
authors.lastname: Li
authors.affiliation: Department of Imaging Physics, Delft University of Technology, Delft, 2628 CH, The Netherlands.
authors.forename: Lei
authors.initials: L
authors.lastname: Wei
authors.affiliation: Department of Microelectronics, Delft University of Technology, Delft, 2628 CT, The Netherlands.
authors.forename: René H
authors.initials: RH
authors.lastname: Poelma
authors.affiliation: Department of Microelectronics, Delft University of Technology, Delft, 2628 CT, The Netherlands.
authors.forename: Sten
authors.initials: S
authors.lastname: Vollebregt
authors.affiliation: Department of Microelectronics, Delft University of Technology, Delft, 2628 CT, The Netherlands.
authors.forename: Jia
authors.initials: J
authors.lastname: Wei
authors.affiliation: Department of Imaging Physics, Delft University of Technology, Delft, 2628 CH, The Netherlands.
authors.forename: Hendrik Paul
authors.initials: HP
authors.lastname: Urbach
authors.affiliation: Department of Microelectronics, Delft University of Technology, Delft, 2628 CT, The Netherlands.
authors.forename: Pasqualina M
authors.initials: PM
authors.lastname: Sarro
authors.affiliation: Department of Microelectronics, Delft University of Technology, Delft, 2628 CT, The Netherlands.
authors.forename: Guo Qi
authors.initials: GQ
authors.lastname: Zhang