Patent ID: 7375400
Filing Date: 2008-05-20
Classification: G09G,H01J

Abstract:
1. An image display device, comprising: a substrate; at least one emitter connected to each of a plurality of cathode electrodes formed on said substrate; a gate electrode disposed adjacent to said emitter; an anode electrode having a fluorescent substance layer for generating luminescence upon impingement of electrons emitted from each of said emitters connected said cathode electrodes; a plurality of cathode current control elements formed on said substrate having a cathode current control power terminal connected to each of said plurality of cathode electrodes, and a cathode current control terminal for controlling current passing through said cathode current control power terminal; a plurality of capacitors each of which is connected to said plurality of cathode current control terminals respectively to keep a voltage corresponding to an amount of electron emission; a plurality of capacitor voltage control power elements including a capacitor voltage control power terminal connected to each of said plurality of capacitors, a first capacitor voltage control terminal mutually connected in a first group to set a voltage kept in each of said plurality of capacitors, a second capacitor voltage control terminal mutually connected in a second group to determine as to which of said plurality of capacitors to be kept in the amount of voltage corresponding to said amount of electron emission; and a gate electrode control circuit for applying a signal to said gate electrode, said signal being changeable in a time rate which is a rate of time when a constant voltage is applied repetitively, wherein said gate electrode control circuit varies said time rate according to ambient brightness.