A Different Perspective on Cholesteric Liquid Crystals Reveals Unique Color and Polarization Changes

ACS Applied Materials & Interfaces
Kyung Min LeeMichael E McConney

Abstract

Planar cholesteric liquid crystals (CLCs) are well known for having vibrant reflective coloration that is associated with the handedness and the pitch length of the helicoidal twist of the liquid crystalline molecules. If one observes these films at oblique angles the reflected colors blue shift with increasing angles from normal. On the other hand, uniform lying helix (ULH) CLCs, where the helicoidal axis lies in the plane of the substrate, are well-known, but are not typically associated with vibrant colors. Here we examine the unique optical properties of CLCs at oblique incidence angles, specifically the spectral and polarization changes associated with switching between planar and ULH CLCs for various incidence angles. At small angles of incidence (0o < ψ < 45o, where ψ is the angle of incidence relative to the surface normal at the substrate-CLC interface), the electrically driven helical re-orientation from planar to ULH results in a blue-shifting of the color and circularly polarized to unpolarized switching behavior. At large angles (45o < ψ < 90o) the behavior is reversed, with a red-shifting color change occurring and the polarization switching from unpolarized to circularly polarized. Modeling of the light propagati...Continue Reading

References

Aug 22, 1994·Proceedings. Biological Sciences·G Westheimer
Apr 13, 1987·Physical Review Letters·J S Patel, R B Meyer
Apr 11, 2006·Nature Materials·Michel Mitov, Nathalie Dessaud
Feb 23, 2010·Optics Express·Timothy J WhiteTimothy J Bunning
Oct 27, 2010·Chemical Communications : Chem Comm·Michael E McConneyTimothy J Bunning
Mar 25, 2011·Advanced Materials·Michael E McConneyTimothy J Bunning
Oct 24, 2012·Advanced Materials·Michel Mitov
Oct 19, 2017·Optics Express·Xiao XiangMichael J Escuti
Jun 30, 2019·Optics Express·Jianghao XiongShin-Tson Wu

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Citations

Aug 10, 2021·Advanced Materials·Jeroen A H P SolMichael G Debije

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