Patent ID: 7773062

Claim:
A method of compensating uniformity of a plurality of electroluminescent (EL) displays, comprising the steps of: a) providing the plurality of EL displays, each having i) one or more light-emitting elements, each light-emitting element comprising a first electrode and a second electrode and at a light-emitting layer formed between the electrodes responsive to a current passing through the electrodes; ii) an external controller; and iii) an electronic circuit responsive to the external controller for causing a current to pass through the electrodes and the light-emitting layer to emit light; b) measuring the performance of the one or more light-emitting elements of each of the EL displays at three or more different code values, wherein the different code values are predetermined and are the same for each of the plurality of EL displays; c) forming at least two different groups of code values from the three or more code values and calculating a linear transformation converting an input signal to a compensated signal from the performance measurements of all the EL displays for each of the groups; d) calculating the difference between the measured performance and compensated signal over the range of code values for each of the groups; e) selecting the linear transformation having a preferred difference; and f) receiving an input signal and employing the selected linear transformation to calculate a compensated signal to drive each OLED display.