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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Utilizing critical angles in sensing partially ordered liquid crystal profile
Alaeddin S Abu-Abed1, Robert G Lindquist
1University of Central Oklahoma, Edmond, OK 73034, USA. aabuabed@uco.edu
Optics Express
|January 7, 2010
Summary
This study introduces a novel optical method to track liquid crystal (LC) profiles in sensors. It uses total internal reflection (TIR) critical angles to determine LC ordering and director orientation.
Area of Science:
- Materials Science
- Optics
- Condensed Matter Physics
Background:
- Liquid crystal (LC) based sensors offer unique properties for various applications.
- Accurate characterization of the nematic uniaxial LC profile is crucial for sensor performance.
- Existing methods for tracking LC orientation and ordering can be complex or limited.
Purpose of the Study:
- To develop and present a new optical approach for tracking the nematic uniaxial liquid crystal (LC) profile.
- To enable the measurement of both the degree of ordering and director axis orientation in partially ordered LC films.
- To utilize the phenomenon of total internal reflection (TIR) for optical transduction.
Main Methods:
- Investigating a novel approach based on measuring critical angles for total internal reflection (TIR).
- Analyzing the interface between optically isotropic materials and partially ordered LC films.
- Measuring the ordinary critical angle and two extraordinary critical angles in orthogonal directions.
Main Results:
- The proposed method allows for precise determination of the LC degree of ordering.
- The technique successfully reports the director axis orientation in orthogonal directions.
- This optical transduction method provides a new way to characterize LC-based sensors.
Conclusions:
- The developed method offers an effective means to track nematic uniaxial LC profiles.
- Measuring TIR critical angles is a viable strategy for LC characterization.
- This technique enhances the understanding and application of partially ordered LC-based sensors.
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