Dual-frequency-addressable photochromic cholesteric mixture with photo- and electro-switchable optical properties

0585808 - FZÚ 2025 RIV NL eng J - Journal Article
Bobrovsky, A. - Shibaev, V. - Bezborodov, V. - Mikhalyonok, S. - Arol, A. - Cigl, Martin - Hamplová, Věra - Bubnov, Alexej
Dual-frequency-addressable photochromic cholesteric mixture with photo- and electro-switchable optical properties.
Journal of Molecular Liquids. Roč. 400, Apr (2024), č. článku 124560. ISSN 0167-7322. E-ISSN 1873-3166
R&D Projects: GA ČR(CZ) GA22-16499S
Institutional support: RVO:68378271
Keywords : cholesteric * liquid crystal * photosensitive mixture * helix pitch * dual-frequency
OECD category: Materials engineering
Impact factor: 6, year: 2022

Cholesteric liquid crystalline mixture with photo-, electro-controllable optical properties was prepared and the features of its switching behavior were demonstrated. The working principle of the obtained switchable cell is based on using dual-frequency-addressable nematic mixture that enables effective control of selectively reflected planar and scattered focal conics texture by applied field frequency modulation. The nematic mixture was doped with the chiral substance in order to induce a cholesteric structure formation with selective light reflection in visible spectral range. Application of low-frequency electric field as well as UV irradiation induces short-wavelength shift of the selective light reflection. The possibility of photopatterning of the obtained electrooptic cells by UV irradiation through mask is demonstrated. It is shown, that application of electric field of different strength and frequency enables smart control of the photorecorded image contrast.
Permanent Link: https://hdl.handle.net/11104/0353490