Next Article in Journal
The Influence of Epitaxial Crystallization on the Mechanical Properties of Polyamide 66/Reduced Graphene Oxide Nanocomposite Injection Bar
Previous Article in Journal
Chemical Crystallography at the Advanced Light Source
Open AccessArticle

Far-field and Fresnel Liquid Crystal Geometric Phase Holograms via Direct-Write Photo-Alignment

Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, NC 27695, USA
Author to whom correspondence should be addressed.
Academic Editors: Liang-Chy Chien and Charles Rosenblatt
Crystals 2017, 7(12), 383;
Received: 1 December 2017 / Revised: 15 December 2017 / Accepted: 18 December 2017 / Published: 20 December 2017
(This article belongs to the Section Liquid Crystals)
We study computer-generated geometric-phase holograms (GPHs) realized by photo-aligned liquid crystals, in both simulation and experiment. We demonstrate both far-field and Fresnel holograms capable of producing far-field and near-field images with preserved fidelity for all wavelengths. The GPHs are fabricated by patterning a photo-alignment layer (PAL) using a direct-write laser scanner and coating the surface with a polymerizable liquid crystal (i.e., a reactive mesogen). We study various recording pixel sizes, down to 3 μm, that are easily recorded in the PAL. We characterize the fabricated elements and find good agreement with theory and numerical simulation. Because of the wavelength independent geometric phase, the (phase) fidelity of the replay images is preserved for all wavelengths, unlike conventional dynamic phase holograms. However, governed by the diffraction equation, the size and location of a reconstructed image depends on the replay wavelength for far-field and near-field GPHs, respectively. These offer interesting opportunities for white-light holography. View Full-Text
Keywords: liquid crystal; direct-write photo-alignment; computer-generated hologram liquid crystal; direct-write photo-alignment; computer-generated hologram
Show Figures

Figure 1

MDPI and ACS Style

Xiang, X.; Kim, J.; Escuti, M.J. Far-field and Fresnel Liquid Crystal Geometric Phase Holograms via Direct-Write Photo-Alignment. Crystals 2017, 7, 383.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

Back to TopTop