The polarization characteristics of diffracted beams from twisted nematic (TN) gratings are investigated. The TN grating is fabricated by exploiting the photoalignment effect in a dye-doped homogeneous liquid-crystal film. Experimental results indicate that the irradiation of an azo-dye-doped liquid-crystal film with appropriate light can induce dye adsorption on a glass substrate. The adsorbed dyes then reorient the liquid-crystal director perpendicular to the pump-beam polarization. The polarizations of the diffracted beams from such a TN grating are systematically studied. The experimental results correlate well with theory. Additionally, the TN grating can be used as a polarization beam splitter.
© 2006 Optical Society of America
Diffraction and Gratings
Original Manuscript: November 23, 2005
Revised Manuscript: February 10, 2006
Manuscript Accepted: March 21, 2006
Wei-Yen Wu, Ting-Shan Mo, and Andy Ying-Guey Fuh, "Polarization characteristics of diffracted beams from twisted nematic gratings fabricated by the photoalignment effect in dye-doped liquid-crystal films," J. Opt. Soc. Am. B 23, 1737-1742 (2006)