The electro-optical properties of a full v flexible photo-aligned FLC cell are investigated. Two different methods, sticky spacers together with a photo-sensitive monomer and polymer spacers in a regular pattern formed by photo-lithography, are proposed to stabilize the structure in order to increase the bending tolerance of the FLC material during deformation of the cell.
The alignment properties of the azo dye photo-alignment material SD-1/SDA-2 on plastic substrates are investigated. Excellent alignment with high anchoring energy can be achieved with a polarized UV dose less than 1.0 J/cm2. A reflective 6-digit flexible passive matrix driven TN-LCD for smart card applications showing excellent electro-optical properties is demonstrated.
A series of novel bifunctionalized photochromic monomers were synthesized, focusing on those with polymerizable acrylic/methacrylic groups attached to both ends of an azobenzene core via flexible spacers. The phase behaviour of the monomers was investigated using DSC, polarizing optical microscopy and X‐ray diffraction. The change in UV‐vis absorbance of the monomers under illumination with non‐polarized/polarized UV light was studied for both solutions and thin films; also studied was its relaxation in the dark. On illumination with LPUV light, in‐plane reorientation of the molecules normal to the polarization of the exciting UV light, and aggregation of the molecules in the films, were found.
We consider peculiarities in testing flexible reflective liquid-crystal (LC) cells. Several new methods for measuring optical retardation of filled reflective LC cells on plastic substrates are proposed. Cases when the plastic is anisotropic and the LC cell consists of either one or two internal polarizers are studied. The majority of proposed methods can be applied for transmissive LC cells as well as for measuring twist angle.