Blue-phase liquid crystal display with insulating protrusion

ABSTRACT

In order to lower the saturation voltage and enhance the transmittance of in-plane switching blue-phase liquid crystal display (IPS-BPLCD), IPS-BPLCD with insulating protrusion is proposed. The single-protrusion (only set on the top of pixel electrode) and double-protrusion (set on the top of pixel and common electrodes) structures are investigated in this work. The potential distribution changes when the protrusion is used. There is a thicker transverse electric field in BPLC range, because the stronger electric field at the edges of the electrodes is decentralised into BPLC range. As a result, the saturation voltage is reduced from 36.3 V to 28.9 V when the double-protrusion structure is used, and transmittance is increased by ~20%. The contrast ratio is larger than 1000:1 in 60° viewing cone using a half-wave biaxial film. Both single-protrusion and double-protrusion structures have the uniform gamma curves at large oblique viewing angles. Moreover, the off-axis image distortion index is 0.1590 at 60º polar angle when zigzag electrodes are used.

Graphical Abstract

KEYWORDS:

• Blue phase liquid crystal display
• in-plane switching
• gamma shift
• saturation voltage

Acknowledgements

The authors would like to thank Haiwei Chen (Group of Prof. Shin-Tson Wu, University of Central Florida, USA) for his help.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Natural Science Foundation of China [Grant Numbers 61475042, 11304074 and 11274088], the Natural Science Foundation of Hebei Province [Grant Numbers A2015202320 and GCC2014048].