Electrically adjustable thermo-optic switch in a liquid-crystal smart window enabled by a thermoresponsive handedness-reversible chiral dopant

Zheng-Wei Lu^1*, Wei Lee²

¹Institute of Photonic System, National Yang Ming Chiao Tung University, Tainan, Taiwan
²Institute of Imaging and Biomedical Photonics, National Yang Ming Chiao Tung University, Tainan, Taiwan

* Presenter:Zheng-Wei Lu, email:wtf01834@gmail.com

In response to the growing need for energy-efficient smart windows that adapt to light or temperature changes, our pioneering study focuses on characterizing optical transmission varying with temperature change. Conventional approaches often grapple with challenges like fixed switching temperatures or high operating voltages. Recently, we have effectively overcome these limitations by introducing a thermosensitive chiral dopant characterized by the unique ability to reverse handedness. Here our innovative approach capitalizes on the properties of a dual-frequency liquid crystal (DFLC), which exhibits either negative or positive dielectric anisotropy at different frequencies. This flexibility allows us to vary the switching temperature at different frequencies with low voltage regulation. Furthermore, we have leveraged the positive correlation between the crossover frequency and temperature of DFLC to develop both normal-mode and reverse-mode smart windows. These windows offer permit remarkable adjustability, enabling mode switching and customizable switching temperatures. Our research not only tackles the constraints of conventional smart window technology but also lays the foundation for improving energy efficiency and user comfort.

Keywords: Thermoresponsive Chiral Dopant, Dual-Frequency Liquid Crystals, Crossover Frequency