Dynamic tuning of reflection band width in cholesteric liquid crystals

Abstract

We report electro-optic effects in a planarly aligned cholesteric liquid crystal (ChLC) using an interdigitated array electrode with a pitch of 10 m between adjacent electrodes. In a cell with a thickness of 10 m, the electrode products distribution of electric field intensities in the thickness direction of the cell because of the narrow pitch between electrodes. When the electric field was applied to a ChLC with planar alignment, the reflection band width of the ChLC was broadened. The maximum band width showed approximately 300 nm, which was three times wider than the original band width at zero field. The broadening of the band width is attributed to distribution of the helical pitch induced by the field-intensity distribution in the thickness direction of the cell.