Patent ID: 7742026

Claim:
A method of determining driving signals for a four-color organic electroluminescence device, wherein said driving signals include a white signal, a red signal, a green signal, and a blue signal to drive the pixel presenting a predetermined color, a three-color organic electroluminescence device being used as a reference, a pixel of the three-color organic electroluminescence device being driven by a red reference signal, a green reference signal, and a blue reference signal to present said predetermined color, the method comprising: defining a value of the white signal to be the lowest value among the red reference signal, the green reference signal, and the blue reference signal; defining a value of the red signal equal to the difference between the value of the red reference signal and the white signal, defining a value of the green signal equal to the difference between the value of the green reference signal and the white signal, and defining a value of the blue signal equal to the difference between the value of the blue reference signal and the white signal; and adjusting the values of the red signal, the green signal, or the blue signal to compensate color shifting resulted from a four-color organic electroluminescence device of the pixel, wherein the adjustment includes a white balance process comprising: detecting a difference between a first color displayed while only turning on the white sub-pixel of a four-color organic electroluminescence device and a pure white; compensating the first color to the pure white by using one or combination of the red sub-pixel, the green sub-pixel and the blue sub-pixel; and recording the values of the red sub-pixel, the green sub-pixel and the blue sub-pixel to be a compensating red signal, a compensating green signal, and a compensating blue signal.