Organic light emitting diode display device and method for manufacturing the same

• US 10,453,902 B2
• Filed: 12/13/2013
• Issued: 10/22/2019
• Est. Priority Date: 12/31/2012
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Lee, Kang Ju, Im, Hun Bae
• Primary Examiner(s): Li, Meiya
• Application Number:
  US14/105,980
• Publication Number:
  US 20140183480A1
• Time in Patent Office: 2,139 Days
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/852 comprising a resonant cavity structure, e.g. Bragg reflector pair
• CPC Class Codes: H10K 50/865 comprising light absorbing layers, e.g. light-blocking layers
• CPC Class Codes: H10K 59/351 comprising more than three subpixels, e.g. red-green-blue-white [RGBW]
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]
• CPC Class Codes: H10K 59/876 comprising a resonant cavity structure, e.g. Bragg reflector pair
• CPC Class Codes: H10K 59/8792 comprising light absorbing layers, e.g. black layers

Abstract

An OLED display device which prevents a color change according to a viewing angle. The OLED display device may include a substrate defined by a first pixel, a second pixel, a third pixel and a fourth pixel; an anode electrode on the substrate; a first organic light-emitting layer for emitting a first color light; a second organic light-emitting layer for emitting a second color light; a cathode electrode formed of a semi-transparent metal material on the first or second organic light-emitting layer, wherein the first organic light-emitting layer is formed in the first pixel and the second pixel; the second organic light-emitting layer is formed in the second pixel, the third pixel and the fourth pixel; and the second pixel emits mixed light of the first color light and the second color light.

Claims

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

a substrate defined by a first pixel, a second pixel, a third pixel and a fourth pixel;

a reflection layer deposited on the substrate, the reflection layer being a single layer including at least one of silver or aluminum;

an anode electrode on the reflection layer;

a light-absorbing layer formed between the reflection layer and the anode electrode in the second pixel;

a cathode electrode of a semi-transparent metal material on the anode electrode, and

an organic light-emitting layer between the anode electrode and the cathode electrode, the organic light-emitting layer comprising a first organic light-emitting layer that emits a first color light and a second organic light-emitting layer that emits a second color light different from the first color light,

wherein the organic light-emitting layer in the first pixel consists of only the first organic light-emitting layer and emits the first color light,

wherein the organic light-emitting layer in the second pixel consists of both the first organic light-emitting layer and the second organic light-emitting layer, and emits mixed light of the first color light and the second color light,

wherein the organic light-emitting layer in the third pixel and the fourth pixel consist of only the second organic light-emitting layer, and emits the second color light, and

wherein a material of the light-absorbing layer is different than that of the reflection layer.

2. The OLED display device of claim 1, wherein the mixed light of the first color light and the second color light has a white color.

3. The OLED display device of claim 2, wherein the first organic light-emitting layer emits a blue color light, the second organic light-emitting layer emits a yellow color light, and the mixed light corresponds to a white color light.

4. The OLED display device of claim 1, wherein the reflection layer and the cathode electrode are apart from each other.

5. The OLED display device of claim 1, further comprising a semi-transparent layer, on the light-absorbing layer of the second pixel.

6. The OLED display device of claim 1, further comprising a color refiner refining a light emitted in the organic light-emitting layer so that the refined light is displayed.

7. The OLED display device of claim 6, wherein the color refiner comprises a blue color refiner in the first pixel, a green color refiner in the third pixel, and a red color refiner in the fourth pixel.

8. The OLED display device of claim 7, wherein the green color refiner converts the second color light into a green color light, and the red color refiner converts the second color light into a red color light.

9. The OLED display device of claim 6, wherein the color refiner is formed on the cathode electrode.

10. The OLED display device of claim 6, wherein the reflection layer is positioned between the color refiner and the substrate.

11. The OLED display device of claim 1, further comprising a semi-transparent layer formed between the anode electrode and the light-absorbing layer in the second pixel.

12. The OLED display device of claim 1, wherein the light-absorbing layer has a reflectance less than 10% for wavelengths corresponding to the visible range.

13. The OLED display device of claim 1, wherein the reflection layer is directly on and in contact with the substrate.

14. A method for manufacturing an OLED display device, comprising:

providing and defining a substrate by a first pixel, a second pixel, a third pixel and a fourth pixel;

forming a reflection layer on the substrate, the reflection layer being a single layer including at least one of silver or aluminum;

forming an anode electrode on the reflection layer;

forming a light-absorbing layer between the reflection layer and the anode electrode, a material of the light-absorbing layer being different than that of the reflection layer;

forming a cathode electrode of a semi-transparent metal material on the anode electrode, and

forming an organic light-emitting layer between the anode electrode and the cathode electrode, the organic light-emitting layer comprising a first organic light-emitting layer that emits a first color light and a second organic light-emitting layer that emits a second color light different from the first color light,

wherein the organic light-emitting layer in the first pixel consists of only the first organic light-emitting layer and emits the first color light,

wherein the organic light-emitting layer in the second pixel consists of both the first organic light-emitting layer and the second organic light-emitting layer, and emits mixed light of the first color light and the second color light,

wherein the organic light-emitting layer in the third pixel and the fourth pixel consist of only the second organic light-emitting layer, and emits the second color light.

15. The method of claim 14, wherein the first organic light-emitting layer and the second organic light-emitting layer are formed by a use of shadow mask.

16. The method of claim 15, wherein an open area included in the shadow mask is larger than an area of at least two of the first pixel, the second pixel, the third pixel and the fourth pixel.

17. The method of claim 14, further comprising forming a semi-transparent layer on the light-absorbing layer.