Related Experiment Video
Updated: Dec 14, 2025
10:33
An Electrochemical Cholesteric Liquid Crystalline Device for Quick and Low-Voltage Color Modulation
Published on: February 27, 2019
8.8K
A Different Perspective on Cholesteric Liquid Crystals Reveals Unique Color and Polarization Changes
Kyung Min Lee1,2, Mariacristina Rumi1,2, Matthew S Mills1
1Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB, Ohio 45433, United States.
ACS Applied Materials & Interfaces
|July 17, 2020
Summary
Uniform lying helix (ULH) cholesteric liquid crystals (CLCs) exhibit unique angular chromaticity. Switching between planar and ULH CLCs alters spectral and polarization properties with changing incidence angles.
Area of Science:
- Materials Science
- Optics
- Condensed Matter Physics
Background:
- Planar cholesteric liquid crystals (CLCs) display vibrant colors due to their helical structure.
- Uniform lying helix (ULH) CLCs, with in-plane helicoidal axes, are less known for color.
- Oblique incidence angles cause spectral shifts in planar CLCs.
Purpose of the Study:
- To investigate the optical properties of CLCs at oblique incidence angles.
- To analyze spectral and polarization changes during transitions between planar and ULH CLC states.
- To understand the reconfigurable angular chromaticity of ULH CLCs.
Main Methods:
- Experimental observation of spectral and polarization changes at various incidence angles.
- Electrical switching between planar and ULH CLC configurations.
- Modeling light propagation through ULH CLCs.
Main Results:
- At small incidence angles (0°–45°), planar to ULH switching causes blue-shifting and circular to unpolarized light.
- At large incidence angles (45°–90°), switching results in red-shifting and unpolarized to circular light.
- Experimental observations are confirmed by light propagation modeling.
Conclusions:
- ULH CLCs exhibit unique optical behaviors at oblique incidence angles.
- The study reveals a novel reconfigurable angular chromaticity in ULH CLCs.
- This work offers new insights into the optical properties of ULH CLCs.
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