Luminance compensation for emissive displays

• US 20030071821A1
• Filed: 10/11/2001
• Published: 04/17/2003
• Est. Priority Date: 10/11/2001
• Status: Abandoned Application

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Booth, Lawrence A. Jr., Sundahl, Robert C.
• Application Number:
  US09/976,199
• Publication Number:
  US 20030071821A1
• Time in Patent Office: Days
• US Class Current: 345/589
• CPC Class Codes: G09G 2320/0295 by monitoring each display pixel
• CPC Class Codes: G09G 2320/045 Compensation of drifts in the characteristics of light emitting or modulating elements
• CPC Class Codes: G09G 2360/147 the originated light output being determined for each pixel
• CPC Class Codes: G09G 3/14 Semiconductor devices, e.g. diodes
• CPC Class Codes: G09G 3/3208 organic, e.g. using organic light-emitting diodes [OLED]
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: H05B 45/60 Circuit arrangements for operating LEDs comprising organic material, e.g. for operating organic light-emitting diodes [OLED] or polymer light-emitting diodes [PLED]
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

Briefly, this is a disclosure of embodiments of a technique, an apparatus, and a system for luminance compensation for emissive displays.

Claims

1. A method for at least partially compensating luminance of an emissive display comprising:

estimating the amount of degradation of one or more organic light emitting diodes (OLEDs) included in said emissive display; and

adjusting the luminance of said one or more OLEDs based, at least in part, upon said estimate.

2. The method of claim 1, wherein adjusting comprises adjusting the luminance so that said luminance remains substantially constant substantially independent of the amount of degradation of said one or more OLEDs.

3. The method of claim 2, wherein estimating includes estimating a characteristic substantially correlated with said degradation.

4. The method of claim 3, wherein said estimating includes measuring the voltage across said one or more OLEDs at a substantially constant current flow through said one or more OLEDs.

5. The method of claim 2, wherein measuring said voltage across said one or more organic light emitting diodes (OLEDs) includes measuring the reverse bias resistance of said one or more OLEDs.

6. The method of claim 1, wherein adjusting includes adjusting the amount of electrical energy applied to said one or more organic light emitting diodes (OLEDs).

7. The method of claim 6, wherein adjusting includes increasing the voltage applied across said one or more OLEDs.

8. The method of claim 7, wherein increasing includes utilization of a lookup table.

9. The method of claim 8, wherein said lookup table includes values such that the luminance of said one or more organic light emitting diodes (OLEDs) achieved by the adjustment essentially decreases over time.

10. The method of claim 1, wherein said method further comprises adjusting the luminance of said one or more organic light emitting diodes (OLEDs) based, at least in part, upon estimating the amount of degradation of one or more other organic light emitting diodes (OLEDs).

13. The apparatus of claim 1, wherein the estimation of the amount of degradation, made by said measurement circuit, includes an estimation of a characteristic substantially correlated with said degradation.

14. The apparatus of claim 13, wherein said measurement circuit is capable of measuring the reverse bias resistance of said one or more organic light emitting diodes (OLEDs) operating at a substantially constant current.

11. An apparatus comprising:

one or more organic light emitting diodes (OLEDs);

a measurement circuit; and

a control system;

wherein said OLEDs, said measurement circuit and said control system are coupled so that, during operation, said measurement circuit, estimates the amount of degradation of said one or more OLEDS and said control system adjusts the luminance of said OLEDs, based at least in part upon said estimated degradation.

12. The apparatus of claim 11, wherein said control system is capable of adjusting the luminance so that said luminance remains substantially constant substantially independent of the amount of degradation of said one or more OLEDs.

15. The apparatus of claim 12, wherein said control system is capable of adjusting said luminance of said one or more organic light emitting diodes (OLEDs) by adjusting the substantially instantaneous current through said OLEDs.

16. The apparatus of claim 11, wherein said control system comprises a series of data that correlates a desired luminance with the estimated degradation of said one or more OLEDs.

17. The apparatus of claim 16, wherein said control system utilizes said series of data to adjust the luminance of said one or more OLEDs.

18. The apparatus of claim 17, wherein said control system comprises a series of data that correlates a desired luminance with the estimated degradation of said one or more OLEDs such that said desired luminance decreases as said estimated degradation of said one or more OLEDs increases.

19. The apparatus of claim 12, wherein said control system includes a storage medium having a plurality of machine accessible instructions, wherein, when said instructions are executed by said control system, the instructions provide for

utilizing a signal from said measuring circuit;

estimating a desired luminance for said OLEDs; and

adjusting the current applied to said OLEDs based at least in part upon said signal.

20. A system comprising:

a receiver which receives, from a source physically remote from said system, video signals in a digital format;

an array of one or more organic light emitting diodes (OLEDs);

a measurement circuit; and

a control system;

wherein said receiver disperses said digital signals to said array of OLEDs, and

wherein said array of OLEDs, said measurement circuit and said control system are coupled so that, during operation, said measurement circuit, estimates the amount of degradation of said one or more OLEDS and said control system adjusts the luminance of said OLEDs, based at least in part upon said estimated degradation.

21. The system of claim 20, wherein said control system is capable of adjusting the luminance so that said luminance remains substantially constant substantially independent of the amount of degradation of said array of OLEDs.

22. The system of claim 20, wherein the estimation of the amount of degradation, made by said measurement circuit, includes an estimation of a characteristic substantially correlated with said degradation.

23. The system of claim 22, wherein said measurement circuit is capable of measuring the reverse bias resistance of said at least one OLED operating at a substantially predetermined current.

24. The system of claim 22, wherein said control system is capable of adjusting said luminance of said array of organic light emitting diodes (OLEDs) by adjusting the substantially instantaneous current through said array of OLEDs.

25. The system of claim 24, wherein control system includes a storage medium having a plurality of machine accessible instructions, wherein, when said instructions are executed by said control system, the instructions provide for

utilizing a signal from said measuring circuit;

estimating a desired luminance for said OLEDs; and

adjusting the current applied to said OLEDs based at least in part upon said signal.

26. The system of claim 24, wherein said control system comprises a series of data that correlates a desired luminance with the estimated degradation of said array of OLEDs and said control system utilizes said series of data to adjust the luminance of said array of OLEDs.

27. The system of claim 26, wherein said control system comprises a series of data that correlates a desired luminance with the estimated degradation of said one or more OLEDs such that said desired luminance decreases as said degradation of said one or more OLEDs increases.

28. The system of claim 21, wherein said control system comprises a plurality of control sub-systems, said respective sub-systems to adjust the output luminance of a particular respective sub-set of said array of one or more organic light emitting diodes (OLEDs).

29. The system of claim 28, wherein the organic light emitting diodes (OLEDs) of said array is coupled to a measurement circuit and control system which is capable of measuring the degradation of said respective OLEDs and is capable of respectively adjusting the luminance of said respective OLEDs.