Files in this item

FilesDescriptionFormat

application/pdf

application/pdf9328993.pdf (4MB)Restricted to U of Illinois
(no description provided)PDF

Description

Title:Organic materials for holographic applications
Author(s):Chen, Alan Gengsheng
Doctoral Committee Chair(s):Payne, David A.
Department / Program:Materials Science and Engineering
Discipline:Materials Science and Engineering
Degree Granting Institution:University of Illinois at Urbana-Champaign
Degree:Ph.D.
Genre:Dissertation
Subject(s):Physics, Optics
Engineering, Materials Science
Abstract:Volume holography plays an important role in modern optical technology. This research explores organic materials for holographic applications in optical systems. A novel medium composed of azo dye molecules (methyl red sodium salt) and liquid crystals (PCB) was developed for holographic applications. A conformation change of azo dye molecules in cis-trans isomerization reorients liquid crystal molecules. Reversible polarization holograms are recorded dynamically with a threshold intensity as low as 3.0 mW/$cm\sp2$ and a response time from 1 ms to 100 ms depending on the recording spatial frequencies. Surface anchoring forces play a key role in holographic storage. We investigated these forces with differently treated substrates. Optical surface memory effects are described experimentally. We also seek novel materials for dynamic volume holography. Liquid crystal molecules (EBBA and MBBA) have been dispersed in polymer matrices for volume holographic storage. Dynamic holographic effects due to thermal and optically driven anisotropies are observed.
A programmable multilayer holographic storage device using a stack of polarization sensitive polymer films and liquid crystals is developed. The parallel access time is about 10 ms. This device is useful for real-time holographic displays, optical interconnections, and high-density optical data storage. In addition, holography has been employed for spectral filtering. Filtering by a thick hologram can manipulate the amplitude and phase of the spectral components of an optical pulse. A camphorquinone doped polymer resin is used as a volume holographic element. Pulses from a CPM laser are filtered into two or three different frequency components, which beat in the time domain to generate a sub-picosecond pulse with very different shape. The device will find applications in optical communications and time-resolved spectroscopy.
Issue Date:1993
Type:Text
Language:English
URI:http://hdl.handle.net/2142/20260
Rights Information:Copyright 1993 Chen, Alan Gengsheng
Date Available in IDEALS:2011-05-07
Identifier in Online Catalog:AAI9328993
OCLC Identifier:(UMI)AAI9328993


This item appears in the following Collection(s)

Item Statistics