Multicolor fluorescent liquid crystal display using a UV light emitting diode

Multicolor fluorescent liquid crystal (LC) displays using a newly developed UV light emitting diode (UV-LED) as an excitation source are proposed. The fluorescent LC cells are prepared by mixing a cholesteric LC and a blue or green dichroic guest fluorescent dye. A green or red fluorescent film is s tacked on the LC cell. The LC cells work as both a UV shutter and a fluores cent emitter, therefore the fluorescence color can be electrically switched between two fluorescent layers. The multicolor fluorescence switch is also demonstrated in the triple-layered cell; two LC layers (blue and green) an d one fluorescent film (red).