Color OLED display with improved power efficiency

• US 6,919,681 B2
• Filed: 04/30/2003
• Issued: 07/19/2005
• Est. Priority Date: 04/30/2003
• Status: Active Grant

• Current Assignee: Global OLED Technology LLC (LG Display Co., Ltd.)
• Original Assignee: Eastman Kodak Company
• Inventors: Cok, Ronald S., Arnold, Andrew D., Winters, Dustin
• Primary Examiner(s): WILLIAMS, JOSEPH L
• Application Number:
  US10/426,299
• Publication Number:
  US 20040217694A1
• Time in Patent Office: 811 Days
• Field of Search: 313500-512, 315/169.3, 315/169.1, 345/60
• US Class Current: 313/500
• 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 2300/0809 Several active elements per pixel in active matrix panels
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 3/3216 using a passive matrix
• CPC Class Codes: G09G 3/3225 using an active matrix
• CPC Class Codes: H10K 59/351 comprising more than three subpixels, e.g. red-green-blue-white [RGBW]
• CPC Class Codes: H10K 59/352 the areas of the RGB subpixels being different
• CPC Class Codes: H10K 59/353 characterised by the geometrical arrangement of the RGB subpixels

Abstract

A color OLED display includes an array of light emitting OLED pixels, each pixel having three or more gamut elements for emitting different colors of light specifying a gamut and at least one additional element for emitting a color of light within the gamut and wherein the power efficiency of the additional element is higher than the power efficiency of at least one of the three or more gamut elements; wherein all of the gamut elements for each color in the display are arranged in a first direction in a line such that no differently colored gamut element is in the line; wherein the colored gamut elements are arranged in a second direction orthogonal to the first direction in a line such that the colors of the gamut elements alternate in that line; and wherein the additional elements are arranged in lines in both the first and second directions.

Claims

1. A color OLED display, comprising:

a) an array of light emitting OLED pixels, each pixel having three or more gamut elements for emitting different colors of light specifying a gamut and at least one additional element for emitting a color of light within the gamut and wherein the power efficiency of the additional element is higher than the power efficiency of at least one of the three or more gamut elements;

b) wherein all of the gamut elements for each color in the display are arranged in a first direction in a line such that no differently colored gamut element is in the line;

c) wherein the colored gamut elements are arranged in a second direction orthogonal to the first direction in a line such that the colors of the gamut elements alternate in that line; and

d) wherein the additional elements are arranged in lines in both the first and second directions.

2. The display claimed in claim 1, wherein the three or more gamut elements emit red, green, and blue colors of light.

3. The display claimed in claim 1, wherein the additional element emits white light.

4. The display claimed in claim 1, wherein the gamut elements are of different sizes.

5. The display claimed in claim 1, wherein the additional element is of a different size from one or more of the gamut elements.

6. The display claimed in claim 1, wherein the display is a top emitting device.

7. The display claimed in claim 1, wherein the display is a bottom emitting device.

8. The display claimed in claim 1, wherein the display is an active matrix device.

9. The display claimed in claim 1, wherein the display is a passive matrix device.

10. The display claimed in claim 1, wherein the light emitted by each of the gamut elements has a narrower bandwidth than a bandwidth of light emitted by the additional elements.

11. The display claimed in claim 1, wherein the gamut elements emit red, green, and blue colors of light, the additional element emits white light, and the elements are arranged in an alternating sequence of red, green, blue, and white emitting elements in the second direction.

12. The display claimed in claim 1, wherein the gamut elements emit red, green, and blue colors of light, the additional element emits white light, and the element are arranged in an alternating sequence of red, green, white, and blue emitting elements in the second direction.

13. The display claimed in claim 1, wherein the gamut elements emit red, green, and blue colors of light, the additional element emits white light, and the elements are arranged in an alternating sequence of red, white, green, and blue emitting elements in the second direction.

14. The display claimed in claim 1, wherein the gamut elements emit red, green, and blue colors of light, the additional element emits white light, and the gamut elements are arranged in a sequence that alternates in the second direction while the additional elements alternate with the gamut elements in the second direction, and reflections and rotations thereof.

15. The display claimed in claim 14, wherein the additional element extends the same distance in the first direction as the gamut elements taken together.

16. The display claimed in claim 1, wherein the gamut elements emit red, green, and blue colors of light, the additional element emits white light, and the additional element is arranged between two of the gamut elements in a pixel, and reflections and rotations thereof.

17. The display claimed in claim 16, wherein the additional element and the green light emitting gamut element are arranged between the red and blue light emitting gamut elements and the green light emitting element is located above or below the white element and reflections and rotations thereof.

18. The display claimed in claim 1, wherein the gamut elements emit red, green, and blue colors of light, the additional element emits white light, and the additional element has a long dimension that is equal to the width or height of a pixel, and reflections and rotations thereof.

19. The display claimed in claim 8, wherein the pixels includes three gamut elements and one additional element, and further comprising active matrix drive circuitry associated with each light emitting element including a select transistor, a storage capacitor, and a power transistor.

20. The display claimed in claim 19, where each pixel is driven by four data lines, each data line being connected to a different light emitting element in the pixel.

21. The display claimed in claim 19, further comprising three power lines per pixel.

22. The display claimed in claim 19, further comprising two power lines per pixel in a row, two light emitting elements of each pixel being connected to each power line.

23. The display claimed in claim 22, wherein two of the four light emitting elements in a pixel are connected to a first power line and the other two light emitting elements are connected to a second power line.

24. The display claimed in claim 19, further comprising three power lines for every two adjacent pixels in a row.