Organic light emitting diode display

• US 9,070,896 B2
• Filed: 04/03/2013
• Issued: 06/30/2015
• Est. Priority Date: 06/01/2012
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Kim, Ki-Wook, Noh, Dae-Hyun
• Primary Examiner(s): YUSHINA, GALINA G
• Application Number:
  US13/856,308
• Publication Number:
  US 20130320314A1
• Time in Patent Office: 818 Days
• Field of Search: 257/40, 257/59, 257/72, 257/E51.001, 257/E21.018, 257/E21.022, 345/212, 345/204, 349/39, 349/38, 349/108
• US Class Current: 1/1
• CPC Class Codes: H10K 50/80 Constructional details
• CPC Class Codes: H10K 50/852 comprising a resonant cavity structure, e.g. Bragg reflector pair
• CPC Class Codes: H10K 59/121 characterised by the geometry or disposition of pixel elements
• CPC Class Codes: H10K 59/1216 the pixel elements being capacitors
• CPC Class Codes: H10K 59/123 Connection of the pixel electrodes to the thin film transistors [TFT]
• CPC Class Codes: H10K 59/876 comprising a resonant cavity structure, e.g. Bragg reflector pair

Abstract

An OLED display includes: a substrate; a first signal line provided on the substrate; a second signal line crossing the first signal line; a thin film transistor connected to the first signal line and the second signal line; a pixel electrode connected to a drain electrode of the thin film transistor; an emission layer formed on the pixel electrode; a common electrode formed on the emission layer and formed of a reflective material; and a capacitor overlapping the pixel electrode.

Claims

1. An organic light emitting diode (OLED) display device, comprising:

a substrate;

a first signal line provided on the substrate;

a second signal line crossing the first signal line;

a thin film transistor connected to the first signal line and the second signal line;

first and second pixel electrodes connected to a drain electrode of the thin film transistor;

a first emission layer formed on the first pixel electrode, a second emission layer formed on the second pixel electrode;

a common electrode formed on the first emission layer and second emission layer and comprising a reflective material; and

the second pixel electrode and a majority of a surface of the second emission layer overlapping a capacitor.

2. The OLED display device of claim 1, wherein the capacitor comprises a first capacitor electrode and a second capacitor electrode that overlap each other with reference to a dielectric material;

and

wherein at least one of the first capacitor electrode and the second capacitor electrode is formed of a transparent conductive material.

3. The OLED display device of claim 2, wherein the pixel electrodes are formed of a transparent conductive material.

4. The OLED display device of claim 2, wherein the first capacitor electrode is connected to a semiconductor of the thin film transistor, and the second capacitor electrode is connected to a capacitor line.

14. The OLED display device of claim 1, the capacitor is electrically connected to the thin film transistor and the second pixel electrode is provided on the capacitor.

5. An organic light emitting diode (OLED) display device comprising a plurality of pixels, wherein each pixel includes:

a capacitor connected to a thin film transistor; and

an emission unit controlled by the thin film transistor;

wherein the emission unit comprises a plurality of sub-emission units and each of the plurality of sub-emission units is electrically connected to the thin film transistor,

a majority of a surface of one of the plurality of sub-emission units bounded by a pixel defining layer overlapping the capacitor.

6. The OLED display device of claim 5, wherein at least one of the plurality of sub-emission units is provided on the capacitor.

7. The OLED display device of claim 6, wherein each of the plurality of sub-emission units comprises:

a pixel electrode;

an emission layer formed on the pixel electrode; and

a common electrode formed on the emission layer.

8. The OLED display device of claim 7, wherein the capacitor comprises a first capacitor electrode and a second capacitor electrode that overlap each other with reference to a dielectric material, and wherein the pixel electrode provided on the capacitor is disposed to overlap a portion within a boundary line of an adjacent surface of the capacitor.

9. The OLED display device of claim 8, wherein at least one of the first capacitor electrode and the second capacitor electrode is formed of a transparent conductive material.

10. The OLED display device of claim 9, wherein the first capacitor electrode is formed of a same material as a semiconductor of a thin film transistor.

11. The OLED display device of claim 7, wherein the pixel electrode is formed of a transparent material and the common electrode is formed of a reflective material.

12. The OLED display device of claim 5, further comprising a semi-transparent layer overlapping at least one pixel electrode.

13. An organic light emitting diode (OLED) display device, comprising:

a substrate;

a first signal line provided on the substrate;

a second signal line crossing the first signal line;

a thin film transistor connected to the first signal line and the second signal line;

a first pixel electrode electrically connected to the thin film transistor;

a second pixel electrode electrically connected to the first pixel electrode;

an emission layer formed on the first pixel electrode and the second pixel electrode;

a common electrode formed on the emission layer; and

a capacitor electrically connected to the thin film transistor;

the second pixel electrode is provided on the capacitor;

a majority of a surface of the emission layer bounded by a pixel defining layer overlapping a capacitor.

15. The OLED display device of claim 13, wherein the second pixel electrode is disposed within a boundary line of an adjacent surface of one of the first capacitor electrode and the second capacitor electrode.

16. The OLED display device of claim 15, wherein the first capacitor electrode is connected to a semiconductor of the thin film transistor, and the second capacitor electrode is connected to a capacitor line.

17. The OLED display device of claim 16, wherein the second capacitor electrode is formed of a transparent conductive material.

18. The OLED display device of claim 13, wherein the first pixel electrode and the second pixel electrode are formed of a transparent conductive material.

19. The OLED display device of claim 18, wherein the first pixel electrode and the second pixel electrode are connected to each other through a contact hole.

20. The OLED display device of claim 19, wherein the first pixel electrode is provided of a same layer as a gate electrode of the thin film transistor is provided.

21. The OLED display device of claim 18, wherein the first pixel electrode and the second pixel electrode are provided of a same layer.

22. The OLED display device of claim 21, further comprising a semi-transparent layer provided between the first pixel electrode and the substrate.

23. The OLED display device of claim 13, wherein the common electrode is formed of a reflective material.