Pixel circuit structure and method for driving the same

• US 10,056,030 B2
• Filed: 08/31/2015
• Issued: 08/21/2018
• Est. Priority Date: 04/21/2015
• Status: Active Grant

• Current Assignee: AU Optronics Corporation
• Original Assignee: AU Optronics Corporation
• Inventors: Wu, Tsung-Tien, Lin, Tsung-Yi, Chang, Cheng-Chieh, Liu, Pin-Miao, Liu, Kang-Hung
• Primary Examiner(s): Mehmood, Jennifer
• Assistant Examiner(s): NOKHAM, JAMES S
• Application Number:
  US14/840,190
• Publication Number:
  US 20160314731A1
• Time in Patent Office: 1,086 Days
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 2300/0804 Sub-multiplexed active matrix panel, i.e. wherein one active driving circuit is used at pixel level for multiple image producing elements
• CPC Class Codes: G09G 2300/0814 used for selection purposes, e.g. logical AND for partial update
• CPC Class Codes: G09G 3/3225 using an active matrix

Abstract

A pixel structure includes a plurality of sub-pixels. Each of the sub-pixels includes a first light-emitting diode (LED) and a second LED. The first LED is configured to emit a first color light. The second LED is configured to emit a second color light. Each of the first LED and the second LED includes an anode and a cathode. The anode of the first LED and the anode of the second LED are coupled to a same signal line. The cathode of the first LED and the cathode of the second LED are coupled to different signal lines.

Claims

1. A pixel structure comprising:

a plurality of sub-pixels, each of the sub-pixels comprising;

a first light-emitting diode (LED) configured to emit a first color light; and

a second LED configured to emit a second color light;

wherein each of the first LED and the second LED comprises an anode and a cathode, the anode of the first LED and the anode of the second LED are coupled to a same signal line, the cathode of the first LED and the cathode of the second LED are coupled to different signal lines,

wherein the first color light is the same as the second color light, and a frequency spectrum peak value of the first color light is different from a frequency spectrum peak value of the second color light.

2. The pixel structure of claim 1, wherein the first LED emits the first color light during a first period, and the second LED emits the second color light during a second period.

3. The pixel structure of claim 2, wherein the anode of the first LED and the anode of the second LED are both coupled to a first signal line, and the cathode of the first LED and the cathode of the second LED are respectively coupled to a second signal line and a third signal line.

4. The pixel structure of claim 3, wherein the second signal line is coupled to a first common electrode, and the third signal line is coupled to a second common electrode, wherein the first common electrode provides a high-level first common voltage to the second signal line during the first period, and provides a low-level first common voltage to the second signal line during the second period, wherein the second common electrode provides a high-level second common voltage to the third signal line during the second period, and provides a low-level second common voltage to the third signal line during the first period.

5. The pixel structure of claim 4, further comprising:

a driving circuit coupled to the first signal line, wherein the driving circuit is configured to control the first LED in cooperation with the first common electrode, and control the second LED in cooperation with the second common electrode.

6. The pixel structure of claim 5, wherein the driving circuit is configured to provide a driving signal to the first signal line, wherein the driving signal comprises various voltage levels, or the driving signal comprises various periods.

7. The pixel structure of claim 2, wherein when the first LED emits light, the second LED does not emit light, when the second LED emits light, the first LED does not emit light.

8. The pixel structure of claim 1, wherein the frequency spectrum peak value of the first color light corresponds to a first wavelength, and the frequency spectrum peak value of the second color light corresponds to a second wavelength, wherein a wavelength difference between the first wavelength and the second wavelength is substantially less than or equal to 50 nanometers.

9. The pixel structure of claim 1, wherein each of the sub-pixels further comprises:

a third LED configured to emit a third color light;

wherein the first color light, the second color light, and the third color light are the same, and a frequency spectrum peak value of the first color light, a frequency spectrum peak value of the second color light, and a frequency spectrum peak value of the third color light are different.

10. The pixel structure of claim 1, wherein each of the sub-pixels further comprises:

a third LED configured to emit a third color light;

wherein the third LED comprises an anode and a cathode, the anode of the first LED, the anode of the second LED, and the anode of the third LED are coupled to the same signal line, and the cathode of the first LED, the cathode of the second LED, and the cathode of the third LED are coupled to different signal lines.

11. The pixel structure of claim 10, wherein the anode of the first LED, the anode of the second LED and the anode of the third LED are all coupled to a first signal line, and the cathode of the first LED, the cathode of the second LED, and the cathode of the third LED are respectively coupled to a second signal line, a third signal line, and a fourth signal line.

12. The pixel structure of claim 11, wherein the second signal line receives a high-level first common voltage during a first period, the third signal line receives a high-level second common voltage during a second period, and the fourth signal line receives a high-level third common voltage during a third period.

13. The pixel structure of claim 12, further comprising:

a driving circuit coupled to the first signal line and configured to provide a driving signal to the first signal line, wherein the driving signal comprises various voltage levels, or the driving signal comprises various periods, wherein the driving circuit is configured to control the first LED according to the driving signal and the first common voltage, and control the second LED according to the driving signal and the second common voltage, and control the third LED according to the driving signal and the third common voltage.

14. The pixel structure of claim 10, wherein the plurality of sub-pixels comprise a first sub-pixel, a second sub-pixel, and a third sub-pixel, wherein the first sub-pixel, the second sub-pixel, and the third sub-pixel respectively emit one of the first color light, the second color light, and the third color light to allow the pixel structure to simultaneously emit the first color light, the second color light, and the third color light.

15. The pixel structure of claim 14, wherein the first LED in the first sub-pixel emits the first color light, the second LED in the second sub-pixel emits the second color light, and the third LED in the third sub-pixel emits the third color light during a first period, wherein the second LED in the first sub-pixel emits the second color light, the third LED in the second sub-pixel emits the third color light, and the first LED in the third sub-pixel emits the first color light during a second period.

16. The pixel structure of claim 15, wherein the third LED in the first sub-pixel emits the third color light, the first LED in the second sub-pixel emits the first color light, and the second LED in the third sub-pixel emits the second color light during a third period.

17. The pixel structure of claim 10, wherein the plurality of sub-pixels comprise a first sub-pixel, a second sub-pixel, and a third sub-pixel, wherein the first sub-pixel, the second sub-pixel, and the third sub-pixel simultaneously emit the first color light during a first period, and the first sub-pixel, the second sub-pixel, and the third sub-pixel simultaneously emit the second color light during a second period.

18. The pixel structure of claim 17, wherein the first sub-pixel, the second sub-pixel, and the third sub-pixel simultaneously emit the third color light during a third period.

19. The pixel structure of claim 17, wherein the first sub-pixel, the second sub-pixel, and the third sub-pixel simultaneously emit the first color light, the second color light, and the third color light during a third period, or the first sub-pixel, the second sub-pixel, and the third sub-pixel simultaneously emit any two of the first color light, the second color light, and the third color light during the third period.

20. The pixel structure of claim 1, further comprising:

an integrated circuit coupled to the first LED and the second LED and configured to control the first LED and the second LED.

21. The pixel structure of claim 20, further comprising:

a third LED configured to emit a third color light, wherein the integrated circuit is further configured to control the third LED.

22. A method for driving a pixel structure, wherein the pixel structure comprises a plurality of sub-pixels, each of the sub-pixels comprising a first light-emitting diode (LED) and a second LED, wherein each of the first LED and the second LED comprises an anode and a cathode, the anode of the first LED and the anode of the second LED are coupled to a same signal line, and the cathode of the first LED and the cathode of the second LED are coupled to different signal lines, wherein the method for driving the pixel structure comprising:

controlling the first LED to emit a first color light; and

controlling the second LED to emit a second color light,

wherein the first color light is the same as the second color light, and a frequency spectrum peak value of the first color light is different from a frequency spectrum peak value of the second color light.

23. The method for driving the pixel structure of claim 22, wherein controlling the first LED to emit the first color light comprises:

controlling the first LED to emit the first color light during a first period;

wherein controlling the second LED to emit the second color light comprises;

controlling the second LED to emit the second color light during a second period.

24. The method for driving the pixel structure of claim 23, wherein the anode of the first LED and the anode of the second LED are both coupled to a first signal line, and the cathode of the first LED and the cathode of the second LED are respectively coupled to a second signal line and a third signal line, wherein the second signal line is coupled to a first common electrode, and the third signal line is coupled to a second common electrode, wherein the method for driving the pixel structure further comprises:

providing a high-level first common voltage to the second signal line during the first period and providing a low-level first common voltage to the second signal line during the second period by the first common electrode; and

providing a high-level second common voltage to the third signal line during the second period and providing a low-level second common voltage to the third signal line during the first period by the second common electrode.

25. The method for driving the pixel structure of claim 24, wherein the pixel structure further comprises a driving circuit, the driving circuit is coupled to the first signal line, wherein controlling the first LED to emit the first color light comprises:

controlling the first LED to emit the first color light by the driving circuit in cooperation with the first common electrode;

wherein controlling the second LED to emit the second color light comprises;

controlling the second LED to emit the second color light by the driving circuit in cooperation with the second common electrode.

26. The method for driving the pixel structure of claim 25, further comprising:

providing a driving signal to the first signal line by the driving circuit, wherein the driving signal comprises various voltage levels, or the driving signal comprises various periods.

27. The method for driving the pixel structure of claim 22, wherein the frequency spectrum peak value of the first color light corresponds to a first wavelength, the frequency spectrum peak value of the second color light corresponds to a second wavelength, wherein a wavelength difference between the first wavelength and the second wavelength is substantially less than or equal to 50 nanometers.

28. The method for driving the pixel structure of claim 22, wherein each of the sub-pixels further comprises a third LED, wherein the method for driving the pixel structure further comprises:

controlling the third LED to emit a third color light, wherein the first color light, the second color light, and the third color light are the same, and a frequency spectrum peak value of the first color light, a frequency spectrum peak value of the second color light, and a frequency spectrum peak value of the third color light are different.

29. The method for driving the pixel structure of claim 28, wherein the plurality of sub-pixels comprise a first sub-pixel, a second sub-pixel, and a third sub-pixel, wherein the method for driving the pixel structure further comprises:

emitting one of the first color light, the second color light, and the third color light by each of the first sub-pixel, the second sub-pixel, and the third sub-pixel to allow the pixel structure to simultaneously emit the first color light, the second color light, and the third color light.

30. The method for driving the pixel structure of claim 29, further comprising:

emitting the first color light by the first LED in the first sub-pixel, emitting the second color light by the second LED in the second sub-pixel, and emitting the third color by the third LED in the third sub-pixel during a first period; and

emitting the second color light by the second LED in the first sub-pixel, emitting the third color light by the third LED in the second sub-pixel, and emitting the first color light by the first LED in the third sub-pixel during a second period.

31. The method for driving the pixel structure of claim 30,

further comprising:

emitting the third color light by the third LED in the first sub-pixel, emitting the first color light by the first LED in the second sub-pixel, and emitting the second color by the second LED in the third sub-pixel during a third period.

32. The method for driving the pixel structure of claim 28, wherein the plurality of sub-pixels comprise a first sub-pixel, a second sub-pixel, and a third sub-pixel, wherein the method for driving the pixel structure further comprises:

simultaneously emitting the first color light by the first sub-pixel, the second sub-pixel, and the third sub-pixel during a first period; and

simultaneously emitting the second color light by the first sub-pixel, the second sub-pixel, and the third sub-pixel during a second period.

33. The method for driving the pixel structure of claim 32,

further comprising:

simultaneously emitting the third color light by the first sub-pixel, the second sub-pixel, and the third sub-pixel during a third period.

34. The method for driving the pixel structure of claim 32,

further comprising:

simultaneously emitting the first color light, the second color light, and the third color light by the first sub-pixel, the second sub-pixel, and the third sub-pixel during a third period, or simultaneously emitting any two of the first color light, the second color light, and the third color light by the first sub-pixel, the second sub-pixel, and the third sub-pixel during the third period.

35. The method for driving the pixel structure of claim 22,

wherein each of

the sub-pixels further comprises a third LED, wherein the third LED comprises an anode and a cathode, wherein the anode of the first LED, the anode of the second LED, and the anode of the third LED are coupled to a first signal line, and the cathode of the first LED, the cathode of the second LED, and the cathode of the third LED are respectively coupled to a second signal line, a third signal line, and a fourth signal line, wherein the method for driving the pixel structure further comprises:

receiving a high-level first common voltage by the second signal line during a first period;

receiving a high-level second common voltage by the third signal line during a second period; and

receiving a high-level third common voltage by the fourth signal line during a third period.

36. The method for driving the pixel structure of claim 35, wherein the pixel structure further comprises a driving circuit, and the driving circuit is coupled to the first signal line, wherein the method for driving the pixel structure further comprises:

providing a driving signal to the first signal line by the driving circuit, wherein the driving signal comprises various voltage levels, or the driving signal comprises various periods;

wherein the method for driving the pixel structure further comprises;

controlling the first LED according to the driving signal and the first common voltage, and controlling the second LED according to the driving signal and the second common voltage, and controlling the third LED according to the driving signal and the third common voltage by the driving circuit.

37. The method for driving the pixel structure of claim 22, wherein the pixel structure further comprises an integrated circuit, and the integrated circuit is coupled to the first LED and the second LED, wherein controlling the first LED to emit the first color light comprises:

controlling the first LED to emit the first color light by the integrated circuit;

wherein controlling the second LED to emit the second color light comprises;

controlling the second LED to emit the second color light by the integrated circuit.