Performance augmentation of bistable cholesteric liquid crystal light shutter- effect of dichroic dye on morphological and electro-optical characteristics

• Published in: Optical materials 2022-05, Vol.127, p.112243, Article 112243
• Main Authors: Gahrotra, Ridhima, Sharma, Vandna, Dogra, Ankit Rai, Malik, Praveen, Kumar, Pankaj
• Format: Article
• Language: English
• Subjects: Cholesteric liquid crystal; Dichroic dye; Electro-optical; Focal-conic and Planar states; Light shutter; Phase transition
• ISSN: 0925-3467; 1873-1252
• DOI: 10.1016/j.optmat.2022.112243

In this article, bistable cholesteric liquid crystal (CLC) light shutters have been fabricated and the effect of dichroic dye on their morphological and electro-optical properties was studied. Experimentally, two different sample cells were prepared for pure CLC and 0.5 wt% dichroic dye (azo orange 3) doped CLC. The morphological behaviour of bistable CLC light shutters observed in transmissive and scattering modes represents planar and focal-conic (FC) states on applied voltages under high and low frequencies, respectively. The voltage-transmission and absorbance characteristics were examined and found the operating voltage lowered with the doping of dichroic dye in CLC. Moreover, dye doped CLC light shutter showed the higher stabilization rate (SR) for planar state along with better contrast ratio (CR) compared with pure CLC light shutter. In addition, phase transition studies of pure and dye doped CLCs have been discussed. •Morphological behaviour of pure and dye doped bistable cholesteric liquid crystals (CLCs) in transmissive and scattering mode.•Bistability of CLC light shutters under zero applied voltage.•Significant reduction of operating voltage with improved contrast ratio (CR) of dye doped bistable CLC light shutter.•Bistability's factor stabilization rate (SR) dependence on electro-optical properties.•Phase transition studies of CLC light shutters.