Patent ID: 8077123
Filing Date: 2011-12-13
Classification: G09G

Abstract:
1. A method of determining compensation needed for reduced light efficiency in aged sub-pixels of an active matrix organic light-emitting diode (OLED) display, the method comprising: applying a predetermined voltage across one or more of reference sub-pixels that are not aged and determining a first current through said one or more of the reference sub-pixels; determining a current difference between the first current and a reference current, the reference current corresponding to current of said one or more of the reference sub-pixels with the predetermined voltage applied to said one or more of the reference sub-pixels at an initial timing, and the current difference being indicative of the change in current of said one or more of the reference sub-pixels due to change in ambient temperature in which the active matrix OLED display is placed; applying the predetermined voltage across an aged sub-pixel and determining a second current through said aged sub-pixel; subtracting the current difference from the second current to obtain a third current, the third correct corresponding to the second current with correction for the change in ambient temperature; determining an age of the aged sub-pixel based on the third current relative to the reference current; selecting one of a plurality of age curve look-up tables to use for correction of digital numbers indicative of desired brightness in said aged sub-pixel based upon the determined age of said aged sub-pixel, each of the plurality of age curve look-up tables corresponding to a different age of the aged sub-pixel and mapping the digital numbers to said corrections to be made to the digital numbers for the corresponding age of the aged sub-pixel and one or more of the aged sub-pixels of the OLED display being assigned to use said one of the age curve look-up tables for correction of the digital numbers.