ELECTRON-BEAM GENERATING DEVICE HAVING PLURALITY OF COLD CATHODE ELEMENTS, METHOD OF DRIVING SAID DEVICE AND IMAGE FORMING APPARATUS APPLYING SAME

摘要

A method and apparatus for driving an electron source in which a high-quality image display is presented by correcting a non-uniform effective current distribution caused in cold cathode elements by leakage current. A digital video signal enters a shift register where a serial-to-parallel conversion is made for each line of an image based upon a shift clock signal. One line of the image data that has been subjected to the serial-to-parallel conversion is latched in a latch circuit and then applied to a voltage modulating circuit. The latter voltage-modulates the input data and sends the modulated signal to a voltage/current converting circuit. The latter converts the voltage quantity to a current quantity, which is applied to each of the cold cathode elements of a display panel through respective column terminals. A voltage V1 is applied to the selected row wire, and a voltage V2 (V2 ? V1) is applied to all other row wires, for controlling the leakage current.