High resolution low power consumption OLED display with extended lifetime

• US 9,424,772 B2
• Filed: 07/17/2014
• Issued: 08/23/2016
• Est. Priority Date: 01/18/2013
• Status: Active Grant

• Current Assignee: Universal Display Corporation
• Original Assignee: Universal Display Corporation
• Inventors: Hack, Michael, Weaver, Michael Stuart, Xu, Xin, So, Woo-Young, Brown, Julia J.
• Primary Examiner(s): Edwards, Carolyn R
• Application Number:
  US14/333,756
• Publication Number:
  US 20140327709A1
• Time in Patent Office: 768 Days
• US Class Current: 1/1
• 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 3/3208 organic, e.g. using organic light-emitting diodes [OLED]
• CPC Class Codes: H10K 59/351 comprising more than three subpixels, e.g. red-green-blue-white [RGBW]

Abstract

Arrangements of pixel components that allow driving three or less of four or more sub-pixels to emit an original color signal are disclosed. A first projection of the original color signal may be projected onto the two sub-pixel'"'"'s color space. The first projection may then be projected onto a second projection corresponding to the color space of a third pixel. The third pixel may be driven based on the second projection only two of the remaining at least three sub-pixels may be driven based on the third pixel being driven.

Claims

1. A method of driving a display pixel comprising at least four sub-pixels, the method comprising:

determining a first projection of an original color signal onto a color space defined by a first and second sub-pixel of the at least four sub-pixels;

determining a second projection of the first projection onto a second color space defined by a third sub-pixel;

driving the third sub-pixel based on the magnitude of the second projection;

driving the second sub-pixel based on the difference between the first projection and the second projection; and

driving the fourth sub-pixel based on a component of the original color signal;

wherein the first sub-pixel is not activated while driving the third sub-pixel based on the magnitude of the second projection and driving the second sub-pixel based on the difference between the first projection and the second projection.

2. The method of claim 1, wherein the third sub-pixel emits a color equivalent to a combination of colors emitted by the first and second sub-pixels.

3. The method of claim 1, wherein the first sub-pixel is a green sub-pixel.

4. The method of claim 1, wherein the first sub-pixel is a red sub-pixel.

5. The method of claim 1, wherein the third sub-pixel is one selected from the group consisting of:

a yellow sub-pixel, a magenta sub-pixel, and a cyan sub-pixel.

6. The method of claim 1, wherein the original color signal is defined by (R, G, B) color coordinates and wherein the third sub-pixel emits light having color coordinates at (r′

, g′

,

     0).

7. The method of claim 6, wherein the third sub-pixel is driven at ((G×

r′

)/g′

, G,

     0), the second sub-pixel is driven at (R−

(G×

r′

)/g′

, 0,

     0), the first sub-pixel is driven at (0, 0,

     0), and the fourth sub-pixel is driven at (0, 0, B).

8. The method of claim 7, wherein g′

/r′

is greater than or equal to G/R.

9. The method of claim 6, wherein the third sub-pixel is driven at (R, (R×

g′

)/r′

,

     0) the second sub-pixel is driven at (0, 0,

     0), the first sub-pixel is driven at (0, G−

(R×

g′

)/r′

,

     0), and the fourth sub-pixel is driven at (0, 0, B).

10. The method of claim 7, wherein g′

/r′

is less than G/R.

11. The method of claim 1, wherein the at least four sub-pixels comprise an emissive region.

12. The method of claim 11, wherein the emissive region contains two or fewer colors.

13. The method of claim 1, wherein the sub-pixels are arranged in a pixel arrangement comprising no more than two color altering layers.

14. The method of claim 1, further comprising:

determining a third projection of a second original color signal onto a color space defined by the first and second sub-pixel of the at least four sub-pixels;

determining a fourth projection, of the third projection, onto the second color space defined by a third sub-pixel;

driving the third sub-pixel based on the magnitude of the fourth projection;

driving the first sub-pixel based on the difference between the first projection and the second projection; and

driving the fourth sub-pixel based on a component of the original color signal;

wherein the second sub-pixel is not activated while driving the third sub-pixel based on the magnitude of the second projection and driving the first sub-pixel based on the difference between the first projection and the second projection.

15. A device comprising a display pixel, wherein the device is configured to operate the display pixel by:

determining a first projection of an original color signal onto a color space defined by a first and second sub-pixel of the at least four sub-pixels;

determining a second projection of the first projection onto a second color space defined by a third sub-pixel;

driving the third sub-pixel based on the magnitude of the second projection;

driving the second sub-pixel based on the difference between the first projection and the second projection; and

driving the fourth sub-pixel based on a component of the original color signal;

wherein the first sub-pixel is not activated while driving the third sub-pixel based on the magnitude of the second projection and driving the second sub-pixel based on the difference between the first projection and the second projection.

16. The device of claim 15, wherein the at least four sub-pixels comprise an emissive region.

17. The device of claim 16, wherein the emissive region contains two or fewer colors.

18. The device of claim 15, wherein the sub-pixels are arranged in a pixel arrangement comprising no more than two color altering layers.

19. A method of driving a display pixel comprising at least four sub-pixels, the method comprising:

determining a first projection of a third sub-pixel color space onto a color space defined by a first and second sub-pixel of the at least four sub-pixels;

determining a second projection of an original color signal onto a color space defined by a first and second sub-pixel of the at least four sub-pixels;

determining a third projection of the second projection onto the first projection;

driving the third sub-pixel based on the magnitude of the third projection;

driving the second sub-pixel based on the difference between the second projection and the third projection; and

driving the fourth sub-pixel based on a component of the original color signal and the difference between the third sub-pixel color space and the first projection;

wherein the first sub-pixel is not activated while driving the third sub-pixel based on the magnitude of the third projection and driving the second sub-pixel based on the difference between the second projection and the third projection.

20. A method of driving a display pixel comprising at least four sub-pixels, the method comprising:

determining a first projection of an original color signal onto a color space defined by a third sub-pixel;

driving the third sub-pixel based on the magnitude of the first projection;

driving a second sub-pixel based on the difference between the original color signal and the first projection; and

wherein the first sub-pixel and the fourth sub-pixel are not activated while the third sub-pixel is driven based on the magnitude of the third projection and second sub-pixel is driven based on the difference between the original color signal and the first projection.