A display system includes a light writable display associated with an identification code and arranged to receive an image wise pattern of light to form an image on the display; a display writer for producing the image wise pattern of light for writing the image on the display; a scanner connected to...http://www.google.es/patents/US7131584?utm_source=gb-gplus-sharePatente US7131584 - Apparatus and means for updating a memory display
