(12) United States Patent ao) Patent No.: us 6,710,760 Bi
Johnson et al. (45) Date of Patent: Mar. 23,2004
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* cited by examiner
Primary Examiner—Amr Awad
(74) Attorney, Agent, or Firm—Raymond L. Owens
A reflective memory display is disclosed which includes: a flexible polymeric substrate; a patterned first conductor disposed over the substrate; and a layer including a polymeric dispersed cholesteric liquid crystal material coated over the first patterned conductor. The memory display further includes a patterned second conductor disposed over the polymeric dispersed cholesteric liquid crystal; and control means for repeatedly applying selective unipolar voltages across particular portions of the patterned first and second conductors to cause electric fields which are applied to portions of the polymeric dispersed cholesteric liquid crystal layer to change its reflectance thereby presenting a series of different reflectance images.
19 Claims, 10 Drawing Sheets