Patent ID: 6897786

Claim:
A traffic sign for use adjacent a vehicle travel lane, the traffic sign being illuminatable during darkness by the lights of vehicles traveling towards the traffic sign and comprising a passively illuminated pixellated display matrix, the display matrix being programmable to display desired information and having: a) a retroreflective layer of light-reflective elements capable of reflecting light received from a traveling vehicle back towards the vehicle driver enabling the traffic sign to be viewed by the lights of the traveling vehicles; and b) an electropolymeric gating layer to gate incident light, the gating layer having an array of contiguous electrostatically actuated polymeric shutter elements defining the display pixel, the shutter elements being movable between open and closed positions in response to a drive signal wherein the polymeric shutter elements comprise: i) a number of prestressed coiled rollouts formed of outwardly metallized flexible polymeric material and providing electrodes movable between the open and closed positions; ii) a transparent dielectric layer having a viewer-facing surface contacted by the metallization of each rollout; and iii) a transparent fixed electrode layer contacting the opposite surface of the dielectric layer; wherein one or more rollouts can be actuated to unroll across the dielectric layer and present a closed shutter appearance by application of a control voltage between the electrode layer and the rollout metallization; wherein an open shutter permits incident light to be reflected from the retroreflective layer toward a viewer providing an open shutter appearance and a closed shutter presents a contrasting appearance to the viewer by daylight and by vehicle light during darkness and wherein the contrasting appearances can be composed to provide text or graphic information images.