Display systems with compensation for line propagation delay

• US 10,176,738 B2
• Filed: 03/06/2018
• Issued: 01/08/2019
• Est. Priority Date: 05/23/2012
• Status: Active Grant

• Current Assignee: IGNIS Innovation Incorporated
• Original Assignee: IGNIS Innovation Incorporated
• Inventors: Chaji, Gholamreza, Azizi, Yaser
• Primary Examiner(s): Edun, Muhammad N
• Application Number:
  US15/913,015
• Publication Number:
  US 20180197447A1
• Time in Patent Office: 308 Days
• CPC Class Codes: G09G 1/002 Intensity circuits G09G1/06 - G09G1/28 take precedence
• CPC Class Codes: G09G 1/12 the deflection signals being produced by essentially analogue means
• CPC Class Codes: G09G 2300/0819 used for counteracting undesired variations, e.g. feedback or autozeroing
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2310/0251 Precharge or discharge of pixel before applying new pixel voltage
• CPC Class Codes: G09G 2320/0223 Compensation for problems related to R-C delay and attenuation in electrodes of matrix panels, e.g. in gate electrodes or on-substrate video signal electrodes
• 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 2320/0693 Calibration of display systems
• CPC Class Codes: G09G 2330/10 Dealing with defective pixels
• CPC Class Codes: G09G 2330/12 Test circuits or failure detection circuits included in a display system, as permanent part thereof
• CPC Class Codes: G09G 3/006 Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309
• CPC Class Codes: G09G 3/18 using liquid crystals
• CPC Class Codes: G09G 3/32 semiconductive, e.g. using light-emitting diodes [LED]
• CPC Class Codes: G09G 3/3225 using an active matrix
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element

Abstract

A method for characterizing and eliminating the effect of propagation delay on data and monitor lines of AMOLED panels is introduced. A similar technique may be utilized to cancel the effect of incomplete settling of select lines that control the write and read switches of pixels on a row.

Claims

1. A method of operating a display system, the method comprising:

generating signals at a first location on a signal line of the display system;

receiving the signals at a second location on the signal line; and

determining a propagation delay effect on the signals as received at the second location with use of the received signals including determining a gain factor between the signals generated at the first location and the signals as received at the second location.

2. The method of claim 1, further comprising:

controlling the operation of the display system with use of the determined propagation delay effect.

3. The method of claim 1, wherein the signal line comprises a data line coupled to a data driver at the first location and coupled to a pixel circuit at the second location.

4. The method of claim 3, further comprising controlling a programming of the pixel circuit to compensate for the propagation delay effect.

5. The method of claim 1, wherein the signal line comprises a monitor line coupled to a pixel circuit at the first location and coupled to a monitor at the second location.

6. The method of claim 5, further comprising controlling a monitoring of the pixel circuit to compensate for the propagation delay effect.

7. The method of claim 1, wherein determining the propagation delay effect comprises determining a signal offset between the signals generated at the first location and the signals as received at the second location.

8. The method of claim 1, wherein said generating and receiving the signals and said determining the propagation delay effect are performed during an initial factory calibration of the display system.

9. A method of operating a display system, the method comprising:

generating signals at a first location on a signal line of the display system;

receiving the signals at a second location on the signal line, each of the received signals at the second location received with use of time periods of different durations; and

determining a propagation delay effect on the signals as received at the second location with use of the received signals.

10. The method of claim 9, wherein at least one of the time periods of different durations is a function of a physical distance between the first location and the second location.

11. The method of claim 9, wherein the time periods of different durations comprise at least a first time period of a duration sufficient to avoid settling effects and a second time period of a duration insufficient to avoid settling effects.

12. The method of claim 11, further comprising:

controlling the operation of the display system with use of the determined propagation delay effect.

13. A display system comprising:

a signal line; and

a controller coupled to the signal line and adapted to

control the display system to;

generate signals at a first location on the signal line; and

receive the signals at a second location on the signal line, and

determine a propagation delay effect on the signals as received at the second location with use of the received signals including determining a gain factor between the signals generated at the first location and the signals as measured at the second location.

14. The display system of claim 13, wherein the controller is further adapted to control the operation of the display system with use of the determined propagation delay effect.

15. The display system of claim 13,

further comprising:

a data driver; and

a pixel circuit,

wherein the signal line comprises a data line coupled to the data driver at the first location and coupled to the pixel circuit at the second location, and wherein the controller is coupled to the data driver and the pixel circuit and is adapted to control the data driver to generate the signals and to control the pixel circuit to receive the signals.

16. The display system of claim 15, wherein the controller is further adapted to control a programming of the pixel circuit to compensate for the propagation delay effect.

17. The display system of claim 13,

further comprising:

a monitor; and

a pixel circuit,

wherein the signal line comprises a monitor line coupled to the pixel circuit at the first location and coupled to the monitor at the second location, and wherein the controller is coupled to the monitor and the pixel circuit and is adapted to control the pixel circuit to generate the signals and to control the monitor to receive the signals.

18. The display system of claim 17, wherein the controller is further adapted to control a monitoring of the pixel circuit to compensate for the propagation delay effect.

19. The display system of claim 13, wherein the controller is adapted to determine the propagation delay effect by determining a signal offset between the signals generated at the first location and the signals as measured at the second location.

20. The display system of claim 13, wherein the controller is adapted to control the display system to generate and receive the signals and to determine the propagation delay effect during an initial factory calibration of the display system.

21. A display system comprising:

a signal line; and

a controller coupled to the signal line and adapted to

control the display system to;

generate signals at a first location on the signal line; and

receive the signals at a second location on the signal line, each of the received signals at the second location received with use of time periods of different durations, and

determine a propagation delay effect on the signals as received at the second location with use of the received signals.

22. The display system of claim 21, wherein at least one of the time periods of different durations is a function of a physical distance between the first location and the second location.

23. The display system of claim 21, wherein the time periods of different durations comprise at least a first time period of a duration sufficient to avoid settling effects and a second time period of a duration insufficient to avoid settling effects.

24. The display system of claim 23, wherein the controller is further adapted to control the operation of the display system with use of the determined propagation delay effect.