Display device with discharge lamp

Claim 1

A discharge lamp type display device, comprising, in combination: (a) at least one discharge lamp, including, in combination: (1) a discharge tube constructed from a dielectric material; and (2) a pair of electrodes disposed within the discharge tube, the tube being elongated and having a pair of spaced ends, an exterior surface being formed between the ends of the tube, one of the said electrodes being a projecting electrode extending longitudinally into the tube from and terminating adjacent to a respective one of the ends of the tube, and the other of the electrodes being a film of electrically conductive, light transmissive material deposited on the exterior surface of the tube and covering all of the exterior surface of the tube only from adjacent the projecting electrode to the other of the end of the tube; and (b) power supply means connected to at least one of the pair of electrodes for applying a driving signal across the electrodes, and including adjusting means for selectively varying the voltage and frequency of the driving signal and variably controlling a region of the tube which is illustrated to sweep from the one end of the discharge tube to the other of the ends thereof.