By use of a trans-cis photoisomerization process occurring in an azo-benzene side chain, various twisted nematic liquid-crystal (LC) gratings are fabricated in LC cells. Two counterpropagating orthogonally polarized beams produce a polarization modulation, which inscribes the replica polarization modulation inside LC cells holographically, providing twisted nematic LC gratings. Microstructure, diffraction properties, and electro-optic tunability of diffraction efficiency are examined experimentally. From the Fourier transformation of the Jones matrix of twisted nematic LC gratings, Stokes parameters of the zeroth and first diffraction orders are calculated and compared with the optical measurements, resulting in a good agreement.
© 2008 Optical Society of America
Original Manuscript: September 8, 2008
Revised Manuscript: October 20, 2008
Manuscript Accepted: October 22, 2008
Published: December 3, 2008
Hyunhee Choi and J. W. Wu, "Optical properties of holographically generated twisted nematic liquid-crystal gratings," J. Opt. Soc. Am. B 26, 1-9 (2009)