Analytic twist angle measurement in liquid crystal cells

Chang-Hun Lee; Salter, P.; Raynes, E. P.; Elston, S. J.
August 2009
Applied Physics Letters;8/24/2009, Vol. 95 Issue 8, p083505
Academic Journal
Previously we have described a method to measure residual twist angle in homogeneously aligned liquid crystal cells by comparing experimental results with simulated data in an electric field. This allows determination of a small twist angle to an accuracy of 0.02°. In this paper, an analytic method is described whereby it is possible to determine the small twist angle directly from the measured transmission without simulation. A simple equation for the twist angle independent of any material parameters is derived and its reliability and accuracy confirmed by comparison with the results of the previous method.


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