Patent ID: 7956826

Claim:
An electroluminescent (EL) display device comprising an array of display pixels, each display pixel comprising an EL display element and a current source circuit for driving a current through the EL display element in dependence on a data voltage, the display device being operable in at least a first and a second phase within each frame period, the first phase having a first duration and during which a first one of a first plurality of drive currents can be driven through the EL display element, and the second phase having a second duration, different to the first duration, and during which a second one of a second plurality of drive currents can be driven through the EL display element, wherein the first and second ones of the respective pluralities of drive currents are independently selectable and at least one of the first and second pluralities of drive currents include more than two drive current levels, and wherein the first plurality of drive currents comprises a number n of drive current levels, including a zero drive level, and wherein a duration of the second phase is approximately n times a duration of the first phase, wherein during said first phase each of the pixel display elements is sequentially driven for said first duration with a corresponding one of said first plurality of drive currents and during said second phase each of the pixel display elements is sequentially driven for said second duration with a corresponding one of said second plurality of drive currents associated with said second phase.