The rise and decay times of the light transmission in a twisted nematic mixture of phenyl benzoates were measured under an ac electric field while switching from one frequency to another. Decay times were drastically reduced by applying a high−frequency electric field at which the dielectric anisotropy has changed sign. A threshold voltage exists for the decay process where the normal oscillation in the light transmission is suddenly and completely suppressed, resulting in a monotonic decay.
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© 1975 American Institute of Physics.
1975
American Institute of Physics
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