A switch/display unit comprises a dot matrix display, having two sets of elongate electrodes, one set being inclined to the other, these sets being applied to opposite sides of a display medium. A transparent dielectric panel is superimposed in front of the display, so that the first set of electrodes,...http://www.google.fr/patents/US4758830?utm_source=gb-gplus-shareBrevet US4758830 - Switch/display units
