Patent ID: 6177767
Filing Date: 2001-01-23
Classification: G09G

Abstract:
A luminescent device comprising:a plurality of luminescing units arranged in a display matrix and so constructed that each of said luminescing units is selectively made to luminesce at a selected brightness by an electric current flowing therethrough;first and second pluralities of line-form electrodes, wherein electrodes of said first plurality intersect electrodes of said second plurality thereby forming said display matrix with a luminescing unit at each intersection, said luminescing units comprising a light-emitting pixel connected at each intersection between intersecting electrodes;wherein said first plurality of line-form electrodes is connected to a driving power supply;wherein each of said second plurality of line-form electrodes is connected to a current control circuit for controlling the current flowing through each luminescing unit to control the brightness thereof in accordance with a brightness control signal;wherein each of the plurality of luminescing units is connected to a respective current control circuit that comprises:a reference resistance for monitoring the current flowing through each of the plurality of luminescing units as a voltage across the reference resistance;a current control device responsive to a control voltage connected between each reference resistance and its respective luminescing unit; andan operational amplifier for comparing the monitored voltage with a voltage representative of the brightness control signal for the respective luminescing unit provided by a memory and outputting the control voltage to said current control device.