Patent ID: 7903324

Claim:
A photoaddressable display medium, comprising: a pair of electrodes, at least one of which has optical transparency; an optical switching element; and a display element including a display layer having a memory effect, wherein the optical switching element comprises: a multi-layered optical switching layer that contains a charge generation layer and a charge transport layer; or a mono-layered optical switching layer that has a charge generating function and a charge transporting function, wherein the charge transport layer or the mono-layered optical switching layer contains a charge transporting material represented by the following general formula (1): wherein R 1 and R 3 each independently represent CH 3 or C 2 H 5 , and R 2 and R 4 each independently represent H, CH 3 or C 2 H 5 ; and wherein the optical switching element and the display element are laminated between the pair of electrodes, and the display element is a color display element having a plurality of display layers relative to the optical switching element, and each of the plurality of display layers is a cholesteric liquid crystal display layer that selectively reflects visible light beams of a color that is different from the color of the visible light beams selectively reflected by any other one of the plurality of display layers.