Angular Dependence of Guest–Host Liquid Crystal Devices with High Pretilt Angle Using Mixture of Vertical and Horizontal Alignment Materials

Abstract

To date, devices exhibiting incidence-angle-dependent transmittance have been fabricated by imparting an angle to a bulk liquid crystal (LC) by aligning the LC in the vicinity of one substrate horizontally (with respect to the substrate) while aligning the LC in the vicinity of another substrate vertically. Another approach has been to control LC angles near substrates by blending or layering horizontal and vertical alignment films. In this study, we control LC angles near substrates by controlling the pretilt angles of blended alignment films; for specific angles, we use dichroic dyes to characterize the incidence angle dependence of these LC devices. Using a guest/host LC device with a pretilt angle near 45°, we successfully construct an LC element with a transmittance peak near a polar angle of 45°.

Optical Filters with Asymmetric Transmittance Depending on the Incident Angle, Produced Using Liquid Crystalline Ink (Louver LC Filters)

“…The authors proposed optical devices using liquid crystal devices (LCDs) with asymmetric transmittance [ 4 , 5 ]. For these devices, hybrid alignment nematic (HAN) LCDs [ 6 , 7 , 8 , 9 , 10 , 11 , 12 ] and LCDs of high pretilt parallel alignment with dichroic dye were used.…”

“…The authors proposed optical devices using liquid crystal devices (LCD asymmetric transmittance [4,5]. For these devices, hybrid alignment nematic LCDs [6][7][8][9][10][11][12] and LCDs of high pretilt parallel alignment with dichroic dye we Combinations of one of these LCDs and a polarizer or two of these LCD half-wave plate could realize effectively asymmetric transmittance dependent o cident angle.…”

“…Furthermore, by using L mers as LC materials and irradiating them with ultraviolet (UV) light, polym possessing an HAN-type structure (Figure 1) can be formed [14][15][16][17][18][19][20][21][22][23]. Figure 2 shows the structure of an optical filter using an HAN-type LC fi polarizer, along with the mechanism for the dependence of the transmittance o cident angle [4,5]. In the case of the optical filters shown in Figure 2, the s-wave sorbed by the polarizer.…”

“…When using a polar transmittance of the filter is less than 50%. Figure 2 shows the structure of an optical filter using an HAN-type LC film and a polarizer, along with the mechanism for the dependence of the transmittance on the incident angle [4,5]. In the case of the optical filters shown in Figure 2, the s-waves are absorbed by the polarizer.…”