43.1: Invited Paper: UB‐FFS: New Materials for Advanced Mobile Applications

Abstract

In the recent years, displays for mobile electronic devices have been revolutionized, mostly driven by smartphones and tablets. Strongest trends are (besides growing sizes) the ever-increasing resolution, improved contrast, very good viewing angle and color performance. This went hand in hand with a trend to more "refined" display technologies, namely fringe field switching (FFS). Now, as the latest step, Ultra-Brightness (UB-) FFS is at the brink to widespread commercialization in mobile and IT displays. It can provide transmittance improvement of more than 15%. The Liquid Crystal (LC) plays a key role here, because UB-FFS uses LCs with negative dielectric anisotropy -whereas "traditional" FFS uses LCs with positive dielectric anisotropy. There are two key challenges. First is providing LCs with a fast switching speed. Second point is keeping the high reliability level of FFS even though completely different materials with much higher challenges on reliability are used. In this paper the recent progress for both key points will be discussed.

Fast response in‐plane switching liquid crystal display mode optimized for high‐resolution virtual‐reality head‐mounted display

“…This assumes that the liquid crystal has a fixed boundary in the x ‐direction orthogonal to it just as it has a fixed boundary in the upper and lower substrates. With respect to the conditions where K 11 is twice the value of K 22 37 and the distance equals the liquid crystal layer thickness d , the response time is expressed by …”

6‐1: Invited Paper: UBplus: New Solution for High Resolution TV

“…The response time of a liquid crystal is proportional to γ1/K22. It was found that there is a close relation of the twist elastic constant (K22) and the splay elastic constant (K11) and that K22 can be approximated as about half of K11 [6]. Due to this result it is possible to estimate the response time by γ1/K11 for in-plane switching test cells.…”

“…Challenges in using a liquid crystal mixture with a negative dielectric anistropy in the past might be based on the higher rotational viscosity (slower switching), lower reliability and lower polarity (higher driving voltages necessary). As a result of continuous development of new liquid crystal materials having a negative dielectric anistropy the drawbacks are becoming less significant [6]. With further developments of new materials UBplus should be able to overcome the last challenges and offer more freedom to the design of future large size, high resolution liquid crystal displays.…”

57.5: Optimized Compensation Film for Automotive Display with Wide Viewing Angle

“…Liquid Crystal Display (LCD) devices have been widely used at automotive display, for instance instrument cluster, center information display [1]. Twisted nematic (TN) [2] mode and Super Fine TFT (SFT) [3][4][5] mode are two popular liquid crystal display modes at Automotive Display. But viewing angle contrast is always serious concern at Automotive Display.…”