Active sensing and compensation for display panel hysteresis
An apparatus receives current image frame data and data relating to at least one previous image frame for an electronic display. One or more parameters related to hysteresis of transistors in the electronic display are sensed. A correlation device, such as a look-up table, receives the sensed parameter or parameters and the data relating to one or more image frames, and uses this information, at least in part, to output an appropriate compensation signal for the current image frame data. The compensated current image frame data may then be supplied to the electronic display to reduce or eliminate the effects of hysteresis on the displayed image.
1. A method of operating an electronic display, the method comprising:
sensing a parameter related to hysteresis of transistors in the electronic display;
obtaining information related to at least one previous image frame displayed on the electronic display; and
compensating, based at least on the parameter and the information, a new image frame to reduce effects of hysteresis of the transistors on the new image frame to be displayed on the electronic display.
2. The method as set forth in claim 1 , wherein sensing the parameter comprises sensing a supply current delivered from the respective transistors to their respective organic light emitting diodes.
3. The method as set forth in claim 1 , wherein sensing the parameter comprises sensing a temperature of the electronic display.
4. The method as set forth in claim 3 , wherein obtaining information comprises storing a look up table that correlates data from the at least one previous image frame to a change in threshold voltage for each of the respective transistors for a plurality of temperatures.
5. The method as set forth in claim 4 , wherein the data comprises previous frame pixel voltage and wherein the change in threshold voltage comprises a corrected change in threshold voltage.
6. The method as set forth in claim 1 , wherein sensing the parameter comprises sensing a threshold voltage of the respective transistors.
7. The method as set forth in claim 1 , wherein obtaining information comprises storing information related to at least one previous image frame displayed on the electronic display.
8. The method as set forth in claim 7 , wherein storing information comprises storing a look up table that correlates data from the at least one previous image frame to a change in threshold voltage for each of the respective transistors.
9. The method as set forth in claim 8 , wherein the data comprises previous frame pixel voltages and wherein the change in threshold voltage comprises a corrected change in threshold voltage.
10. The method as set forth in claim 1 , wherein obtaining information comprises storing information related to a plurality of previous image frames displayed on the electronic display.
11. The method as set forth in claim 10 , wherein storing information comprises storing a look up table that correlates data from the plurality of previous image frames to a change in threshold voltage for each of the respective transistors.
12. The method as set forth in claim 11 , wherein the data comprises respective pixel voltages of the plurality of previous image frames and wherein the change in threshold voltage comprises a corrected change in threshold voltage.
13. The method as set forth in claim 11 , wherein the data comprises a moving average of respective pixel voltages of the plurality of previous image frames and wherein the change in threshold voltage comprises a corrected threshold voltage.
14. An apparatus for operating an electronic display, the apparatus comprising:
means for sensing a parameter related to hysteresis of transistors in the electronic display;
means for obtaining information related to at least one previous image frame displayed on the electronic display; and
means for compensating, based at least on the parameter and the information, a new image frame to reduce effects of hysteresis of the transistors on the new image frame to be displayed on the electronic display.
15. The apparatus as set forth in claim 14 , wherein means for sensing the parameter comprises means for sensing a supply current delivered from the respective transistors to their respective organic light emitting diodes.
16. The apparatus as set forth in claim 14 , wherein means for sensing the parameter comprises means for sensing a temperature of the electronic display.
17. The apparatus as set forth in claim 16 , wherein means for obtaining information comprises means for storing a look up table that correlates data from the at least one previous image frame to a change in threshold voltage for each of the respective transistors for a plurality of temperatures.
18. The apparatus as set forth in claim 17 , wherein the data comprises previous frame pixel voltage and wherein the change in threshold voltage comprises a corrected change in threshold voltage.
19. The apparatus as set forth in claim 14 , wherein means for sensing the parameter comprises means for sensing a threshold voltage of the respective transistors.
20. The apparatus as set forth in claim 14 , wherein means for obtaining information comprises means for storing information related to at least one previous image frame displayed on the electronic display.
21. The apparatus as set forth in claim 20 , wherein means for storing information comprises means for storing a look up table that correlates data from the at least one previous image frame to a change in threshold voltage for each of the respective transistors.
22. The apparatus as set forth in claim 21 , wherein the data comprises previous frame pixel voltages and wherein the change in threshold voltage comprises a corrected change in threshold voltage.
23. The apparatus as set forth in claim 14 , wherein means for obtaining information comprises means for storing information related to a plurality of previous image frames displayed on the electronic display.
24. The apparatus as set forth in claim 23 , wherein means for storing information comprises means for storing a look up table that correlates data from the plurality of previous image frames to a change in threshold voltage for each of the respective transistors.
25. The apparatus as set forth in claim 24 , wherein the data comprises respective pixel voltages of the plurality of previous image frames and wherein the change in threshold voltage comprises a corrected change in threshold voltage.
26. The apparatus as set forth in claim 24 , wherein the data comprises a moving average of respective pixel voltages of the plurality of previous image frames and wherein the change in threshold voltage comprises a corrected threshold voltage.