Photoelectric Properties and Drive Characteristics of GH Liquid-Crystal Cells in Various Alignment Modes

Abstract

Photoelectric properties and drive characteristics of guest-host (GH)-type liquid crystal cells with yellow, magenta, cyan, green, and gray colors using 4-cyano-4'-pentylbiphenyl (5CB) and three diazo-based dichroic dyes were systematically investigated in different driving modes. The dichroic dyes have structures similar to 5CB; therefore, they uniformly mixed and dispersed into the liquid crystal matrix. The green and gray colors were obtained by mixing appropriate ratios of two or more dyes. Impedance of the GH cells decreased upon the incorporation of the dyes into 5CB. However, the photoelectric properties and drive characteristics of the liquid crystal cells were not altered after the inclusion of the dye. In particular, the alignment of the molecules strongly depended on the cell structure. The GH cells in twisted nematic mode exhibited a low driving voltage of approximately 1.5 V.

Effects of Polymer Gel Electrolyte on Photoelectric Properties and Driving Characteristics of Prussian-Blue-Based Electrochromic Cells in Automatic Driving Circuit

“…Measurement of responsiveness of the EC cell was performed by measuring the difference in light transmittance due to the color change that occurred with respect to the application of ±1.5 V every 3 s as the voltage value of the photodiode as in the previous report [20].…”