A Laser-Projection-Programmed Liquid Crystal Platform for Chemical-to-Visual Information Transduction.

Translating molecular-scale chemical interactions into intuitive and information-rich visual representations remains a central challenge in chemical sensing. Liquid crystals (LCs) provide a stimulus-responsive optical medium for chemical-to-optical transduction; however, existing approaches primarily rely on predefined optical responses rather than programmable representations of multiple chemical concentrations. Here, we introduce a laser-projection-programmed LC platform that extends established LC visual sensing toward programmable, multilevel concentration-to-symbol encoding. By integrating near ultraviolet laser-written photoalignment with visible laser readout in a write-read decoupled projection architecture, the LC anchoring configuration and polarization response can be programmed directly through projected optical patterns. Chemically induced changes in LC phase retardation are thereby converted into spatially programmed, naked-eye-readable optical symbols. Using acetone vapor as a model analyte, multiple concentration regimes are programmably encoded into distinct visual symbols, enabling intuitive interpretation of chemical exposure through symbolic visual outputs.