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Updated: Jan 25, 2026
High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Broadband ellipso-polarimetric camera utilizing tunable liquid crystal achromatic waveplate with improved field of
Abstract:
An ellipso-polarimetric camera integrated with improved field of view tunable achromatic waveplate (AWP) over wide spectral band based on nematic liquid crystal retarders is presented. The AWP operates as half, quarter and full waveplate over a wide range of 430-780nm and wide field of view. The proposed analysis proved that capturing images at these modes is sufficient to extract the ellipsometric parameters: sin(2ψ), cos(Δ) and the Stokes parameters S1 and S3, besides showing the relations in between. Transmission and reflection modes setups are demonstrated in addition to an ellipso-polarimetric smartphone camera. The results show for the first time superiority of cos(Δ) images in which prominent contrast and fine details appear even with scattering objects and higher immunity to device errors. Biometric, remote sensing and archeological improved imaging applications are demonstrated.
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