Title Information
Title
Photo-Patterning Studies for Liquid Crystal Alignment
Name: Personal
Name Part
Eakin, James Nelson
Role
Role Term: Text
creator
Origin Information
Copyright Date (keyDate="yes", encoding="w3cdtf")
2008
Physical Description
Extent
xxiv, 169 p.
digitalOrigin
born digital
Note
Thesis (Ph.D.) -- Brown University (2008)
Name: Personal
Name Part
Crawford, Gregory
Role
Role Term: Text
director
Name: Personal
Name Part
Hurt, Robert
Role
Role Term: Text
reader
Name: Personal
Name Part
Zaslavsky, Alexander
Role
Role Term: Text
reader
Name: Corporate
Name Part
Brown University. Division of Engineering. Electrical Sciences and Computer Engineering
Role
Role Term: Text
sponsor
Genre (aat)
theses
Abstract
This dissertation utilizes holographic exposure techniques to manipulate the periodic orientation of liquid crystal materials. Two different exposure techniques are investigated: a polarization holography interference method incident on a photo-responsive surface to induce a preferential ordering, and an amplitude holography interference method that relies on a phase separation and counter-diffusion reaction to create stratified regions of liquid crystal and polymer. In the phase holography investigations, a linear photopolymerizable (LPP) layer is selectively polymerized permanently capturing phase information from the interference patterning and transferring it to align a liquid crystal material. The underlying periodic and frustrated alignment in the one- and two-dimensional alignment configurations is discussed, including the nature of their electro-optic switching transitions. A phenomenological model is presented to describe the Freedericksz transition, or lack thereof, for the registered planar-periodic boundary conditions resulting from the interference of two orthogonal circularly polarized beams. In the amplitude holography investigations, the frustrated chiral and smectic ordering of ferroelectric liquid crystal domains encapsulated by a polymer binder were established. The refractive index modulation in these thin films is modeled as a phase grating that can be electrically addressed to erase the optical diffractive properties. A phenomenological model is developed to take into account a distribution of domain sizes and an effective field that stabilizes the ferroelectric liquid crystal domains. A diffraction model successfully predicts changes in normalized intensities for first-order diffraction with applied field. These gratings demonstrate microsecond-scale response and relaxation times for various grating pitch sizes between 3 and 12 micrometers.
Subject (Local)
Topic
alignment
Subject (Local)
Topic
surface ordering
Subject (FAST) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/999541")
Topic
Liquid crystals
Subject (FAST) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/1070588")
Topic
Polymers
Subject (FAST) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/893514")
Topic
Diffraction
Subject (FAST) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/1046845")
Topic
Optics
Record Information
Record Content Source (marcorg)
RPB
Record Creation Date (encoding="iso8601")
20091218
Language
Language Term: Code (ISO639-2B)
eng
Language Term: Text
English
Identifier: DOI
10.7301/Z0P8496Z
Access Condition: rights statement (href="http://rightsstatements.org/vocab/InC/1.0/")
In Copyright
Access Condition: restriction on access
Collection is open for research.
Type of Resource (primo)
dissertations