[14p-1E-1~17] 12.1 Fabrications and Structure Controls

▼ [14p-1E-8] Three-dimensional vector holograms formed in twisted-nematic azo dye-doped polymer liquid crystal composite

〇(M1)TIEN TRAN¹, Tomoyuki Sasaki¹, Moritsugu Sakamoto¹, Kohei Noda¹, Nobuhiro Kawatsuki², Hiroshi Ono¹ (1.Nagaoka Univ. of Tech., 2.Univ. of Hyogo)

Keywords:hologram,liquid crystal,azo dye-dope polymer

In this presentation, we further investigated the three-dimensional (3D) vector holograms in twisted-nematic photoreactive anisotropic medium and its recorded optical characteristics. The 3D vector holograms has been formed in both homogeneous and twsited-nematic azo dye-doped polymer liquid crystals (LCs) composite. The electric field of the polarized light reorients the director of molecular axis and forms the 3D vector holograms in anisotropic photoreactive LC composites. The 3D distributions of director were extensively investigated by considering the photoalignment of the azo-dye molecules and resulting diffraction properties of the recorded gratings. We also confirmed that the 3D distributions of the director corresponding to the polarization modulation caused not only by light interference and the propagation in LCs, but also by the initial orientation of the LCs. In order to explain the properties, model of the periodical reorientation distribution in homogeneous and twsited-nematic LCs are presented. The extended Jones matrix method is used to describe the interference of two polarized light in anistropic media. Then the finite-difference time-domain (FDTD) method is applied to analyze the diffraction properties of the hologram, recorded in the model medium. In addition, the diffraction efficiency was simulated for various recording conditions to reveal the relationship between the multidimensional structure and the optical behavior.