Viewing angle compensation of vertical alignment liquid crystal display using a triphenylene-based discotic reactive mesogen

Abstract

We synthesised a triphenylene-based discotic reactive mesogen 2,3,6,7,10,11-hexakis(but-3-enyloxy)triphenylene (HABET) and investigated its performance as the compensation film for a vertical alignment-liquid crystal display (VA-LCD). The HABET molecule has a negative birefringence with an extraordinary refractive index (n_e) that is smaller than the ordinary refractive index (n_o). The optic axis of the HABET is parallel to the n_e direction and was vertically aligned to function as a negative C-plate. We measured the refractive indices and birefringence of the HABET layer in the visible wavelength range. Using the experimental data, we simulated the viewing angle property of the VA-LCD with the HABET negative C-plate and a positive A-plate. The viewing angle property of the VA-LCD with the HABET compensation film was wider than those without the compensation film and those using triacetylcellulose films.

Keywords:

• vertical-alignment liquid crystal display
• compensation film
• negative C-plate
• discotic reactive mesogen

Acknowledgement

The authors thank JNC for the LCs and polyimides.

Additional information

Funding

This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning [NRF-2013R1A1A1058681] and the KIST institutional programme. This research was also supported by the Ministry of Trade, Industry & Energy (MOTIE) [10050334] and the Korea Display Research Corporation (KDRC). This research was partially supported by the Basic Research Laboratory program [2015042417].