OSA's Digital Library

Journal of the Optical Society of America B

Journal of the Optical Society of America B

| OPTICAL PHYSICS

  • Vol. 18, Iss. 7 — Jul. 1, 2001
  • pp: 994–1002

Technique for characterizing azimuthal anchoring of twisted nematic liquid crystals using half-leaky guided modes

F. Z. Yang, H. F. Cheng, H. J. Gao, and J. R. Sambles  »View Author Affiliations


JOSA B, Vol. 18, Issue 7, pp. 994-1002 (2001)
http://dx.doi.org/10.1364/JOSAB.18.000994


View Full Text Article

Acrobat PDF (212 KB)





Browse Journals / Lookup Meetings

Browse by Journal and Year


   


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools

Share
Citations

Abstract

The half-leaky guided-mode technique is used to explore the director profile through a thin, twisted, homogeneously aligned nematic liquid-crystal cell (Merck-E7). Twisted alignment is realized by rubbed polyimide layers on both inner walls of the cell. By monitoring first a particular angle of incidence range of the p-to-s-conversion reflectivity for the twisted-nematic cell under high voltage, the direction of the liquid-crystal director on the top interface of the cell, the easy axis, is accurately determined. Then by removing the external voltage and modeling the complete director profile in the cell to fit the half-leaky guided-mode reflectivity data recorded, the real twist of the director from the top to the bottom of the cell is accurately determined. By comparing the surface director orientation at zero volts with the easy axis of the top interface, the azimuthal (in-plane twist) anchoring coefficient, WT, is quantified through knowledge of the twist elastic constant K22. At 26.5 °C we find that for E7, WT=(4.4±0.3)×10−5 J m−2.

© 2001 Optical Society of America

OCIS Codes
(160.3710) Materials : Liquid crystals
(230.3720) Optical devices : Liquid-crystal devices
(240.6700) Optics at surfaces : Surfaces

Citation
F. Z. Yang, H. F. Cheng, H. J. Gao, and J. R. Sambles, "Technique for characterizing azimuthal anchoring of twisted nematic liquid crystals using half-leaky guided modes," J. Opt. Soc. Am. B 18, 994-1002 (2001)
http://www.opticsinfobase.org/josab/abstract.cfm?URI=josab-18-7-994

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Log in to access OSA Member Subscription

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited