Matrix‐Driving Stretchable Structural Colors in Multi‐Pixels Operation Using Chiral Liquid Crystal Elastomers

Abstract

Stretchable structural color technologies are garnering significant attention in photonics for various applications owing to its stretchable flexibility and ability to control the photonic wavelength of light. However, stretchable photonic media, such as chiral liquid crystal elastomers (CLCEs), are subjected to uncontrollable nonuniform strain distribution and position‐dependent color change during the stretching‐assisted color tuning process. Therefore, controlling the colors of the mechanochromic structures is limited to just single‐unit operation level and practically desirable matrix driving mechanochromic devices for multi‐pixel applications have not been realized yet. The study reports position‐independent and multi‐pixel‐driven uniform stretchable structural color switching realized through row and column matrix switching operations by electrically stretchable CLCEs. The uniform strain‐induced color control mechanism and operations of a multi‐arrayed matrix‐driven stretchable color structure are theoretically and experimentally investigated. This breakthrough of a uniform and multi‐pixel color switching of a seven‐segment matrix driving stretchable CLCEs will be a technological leap into full‐scale use of mechanochromic structural colors in practical applications.

Sticky Multicolor Mechanochromic Labels

“…As a desired feature for any label, we demonstrate a method for imprinting color patterns that are either always visible or reversibly revealed or concealed upon mechanical deformation. CLCE patterning is complex and often involves multiple steps combined with temperature, , incorporation of nanoparticles, , chemical modification, , external electronic devices, , and consecutive photocuring and rinsing steps . Toward a much simpler approach, our patterns are imprinted during the ultraviolet (UV) cross-linking in a single step at room temperature.…”

Omnidirectional color wavelength tuning of stretchable chiral liquid crystal elastomers

“…These studies have led to the development of advanced applications for stretchable CLCEs, such as photonic camouflage 36 , chameleon-like e-skin 37 , 38 , biomedical sensors 39 , 40 , and elastomeric fiber technologies 41 , 42 . Moreover, the control of CLCEs in matrix driving of multi-pixel array operations has been reported recently 43 . However, most of the previous reports on wavelength tuning using stretchable CLCEs have been limited to a single directional wavelength shift toward shorter wavelengths rather than multidirectional tuning, which would allow for both broadband and completely unrestricted wavelength control.…”