Determination of azimuthal anchoring energy in grating-aligned twisted nematic liquid crystal layers

Emma L. Wood; G. W. Bradberry; P. S. Cann; J. Roy Sambles

doi:10.1117/12.299984

1 February 1998 Determination of azimuthal anchoring energy in grating-aligned twisted nematic liquid crystal layers

Emma L. Wood, G. W. Bradberry, P. S. Cann, J. Roy Sambles

Proceedings Volume 3318, Liquid Crystals: Physics, Technology, and Applications; (1998) https://doi.org/10.1117/12.299984
Event: Liquid Crystals, 1997, Zakopane, Poland

Abstract

In this work sinusoidal diffraction gratings with a range of pitches and amplitudes are used to algin nematic liquid crystal layers in a twisted homogeneous configuration. The grating profiles are accurately characterized using optical surface plasmon polariton spectroscopy which then allows a calculation of the anchoring energy as predicted by the simple Berreman expression. The experimental Rapini-Papoular anchoring energy is also obtained by a measurement of the director twist away from the alignment direction at room temperature. A linear relationship is found between the two anchoring energies except when it falls below 4 X 10^-7Jm^-2. Noticeably, the correlation between the two theories is hot unity, if room temperature elastic constants are used in the calculation. This apparent inconsistency is explained if the effect of surface memory on the system is considered. Indeed if elastic constant, corresponding to a higher temperature, at which surface memory effects are absent, are used in the Berreman expression, good agreement between the predicted and experimentally measured energies is found.

Citation Download Citation

Emma L. Wood, G. W. Bradberry, P. S. Cann, and J. Roy Sambles "Determination of azimuthal anchoring energy in grating-aligned twisted nematic liquid crystal layers", Proc. SPIE 3318, Liquid Crystals: Physics, Technology, and Applications, (1 February 1998); https://doi.org/10.1117/12.299984

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available