64‐4: Invited Paper: High Contrast Ratio ADS LCD Using Negative Liquid Crystal Material

Abstract

Mini‐LED technology is becoming a mainly driving force in the development of LCD industry. Only using excellent spatial viewing angle characteristics, high picture quality and high contrast ratio LCD panel, Mini‐LED can maximize its effectiveness in improving image quality and has the strength to challenge the dominance of OLED in the high‐end market. As we known, ADS technology belongs to plane field switching display mode, taking into account the excellent wide‐angle characteristics and excellent image quality, has been widely used in mobile phone, tablet, notebook, monitor and TV, the only shortcoming is the low contrast ratio (CR), just at 1000‐1200:1. This paper aims to introduce the development of ultra‐high contrast ADS LCD panel and its implementation method. By using low scattering coefficient negative liquid crystal, fine rubbing alignment process, and fine calibrated POL attachment process, an ultra‐high contrast ratio of CR 3000‐3500:1 is achieved for the first time on ADS panel. The slow response time of negative liquid crystal is improved by balancing the operating voltage (Vop) and adjusting the Cell gap, while the decrease in transmittance caused by lower Cell gap can be overcome by the spectral aperture pixel (SAP) design. All the techniques described in this paper are applicable to various types of plane field switching panels. The paper also concludes with a discussion and outlook on how to further improve the contrast ratio of ADS‐like panel.