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Updated: Jun 1, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Dual-mode operation of a twisted nematic liquid crystal cell by switching between dynamic and memory modes
Dong Han Song1, Ki-Han Kim, Jung-Wook Kim
1School of Electrical Engineering, Pusan National University, Busan 609-735, South Korea.
Abstract:
We propose a twisted nematic liquid crystal device that can be operated in dynamic or memory mode, based on the information content to be displayed at that time. +90°-twisted and -90°-twisted states are used as two stable states for operation in the memory mode. A vertical electric field is applied to realize gray levels for operation in the dynamic mode. The proposed device has a memory retention time of over a month for the memory mode and a response time of 12 ms for the dynamic mode. Contrast ratios of over 500∶1 can be obtained in both the dynamic and memory modes.
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