Influence of different small styryl molecules on electro-optical characteristics of reverse-mode polymer stabilised cholesteric liquid crystal devices

ABSTRACT

Polymer stabilised liquid crystal (PSLC) is widely used in various applications such as smart windows due to its fast response speed and wide viewing angle. However, there are still limitations in terms of high driving voltage and poor contrast ratio. Therefore, there is a need to explore methods to enhance the electro-optical performance of PSLC devices. In this paper, the influence of a few types of styryl molecules on the electro-optical characteristics of PSLC was investigated. The experimental results demonstrated that the addition of an appropriate amount of small styryl molecules significantly reduced the driving voltage and improved the contrast ratio. For an 8-micron-thick sample, the threshold voltage and saturation voltage were approximately 5.3 V and 6.5 V, respectively, resulting in a contrast ratio of approximately 14.4. For a 20-micron-thick sample, the threshold voltage, saturation voltage, and contrast ratio were approximately 10.2 V, 14.5 V, and 109, respectively. Combined with the effects of different small styryl molecules on the morphology of polymer networks, the physical mechanism of different small styryl molecules to improve electro-optical properties was studied. The findings will contribute to the advancement of RPSCLC devices and their practical applications.

GRAPHICAL ABSTRACT

KEYWORDS:

• Reverse-mode polymer-stabilised cholesteric liquid crystals
• styryl molecules
• electro-optical properties
• polymer networks

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by the National Key Research and Development Program of China [Grant Number 2018YFB0703701].