41.5L: Late‐News Paper: Novel Field‐induced Pre‐tilt Alignment Technique Using a Photo‐reactive Alignment Layer for VA LCD

Abstract

We developed a novel LC alignment method for controlling molecular tilt angle by applying a field with photo-reactive polyimide as an alignment layer. This innovative technology establishes a high level VA-LCD whose characteristic is not only fast response time but also a lower black level even more high reliability.

63.2: Pre‐Tilt Alignment Technique via Photo‐Reactive Side Chains on PI Layer for VA LCD

“…2). It implies that the effect of pretilt is generated in the region close to the interface of the LC bulk and PI layer [7], and the distribution of pretile is quite uniform thought out the whole PI surface.…”

“…Not only the response speed is improved but also the contrast ratio and viewing angle become better in PSA mode [6]. However, the LC/monomer mixture may cause the drop-mura effect and the residual monomers may degrade the image quality gradually if the UV curing process is not completed [7]. Although an approach by monomer/PI mixture was suggested to avoid this problem [8], there is a possibility that the uncured monomer may escape from the PI matrix into LC bulk.…”

Field‐induced photo‐reactive alignment technology for the vertical‐alignment liquid‐crystal mode

“…For one of the ITO electrodes we used patterned substrates as a fine slit for one side and non-patterned substrate for the other side. 8 For the other ITO electrode, we used patterned substrates with a patterned VA 2 for both substrates having slits, as shown in Fig. 4.…”

“…In our work, we propose field-induced photo-reactive alignment (FPA) 8,9 as a new method to generate a pre-tilt angle without using any additional monomers. For FPA, a pre-tilt angle can be generated only by using photo-reactive alignment materials as the alignment layer and a UV process under a maintained applied voltage.…”

11.3: Distinguished Paper: High Transmission VA‐LCD with a Three Dimensionally Shaped Pixel Electrode for 4K × 2K Displays

“…A transparent electrode, such as the indium tin oxide (ITO) electrodes used here, covers the entire glass substrate and creates the effective electrical field needed to align liquid crystal (LC) molecules uniformly. This TD electrode is for the vertical alignment (VA) mode of LCDs with pre-tilt technology, such as field-induced photo-reactive alignment (FPA) [1,2] and polymer sustained alignment (PSA) technology [3,4]. By adopting a multi-domain structure, a larger viewing angle can be obtained.…”