Organic Light Emitting Display Device and Method for Manufacturing the Same

Patent metadata

Field	Value
Publication number	US-2020083484-A1
Application number	US-201916526856-A
Country	US
Kind code	A1
Filing date	Jul 30, 2019
Priority date	Sep 6, 2018
Publication date	Mar 12, 2020
Grant date	—

Abstract

An organic light-emitting display device capable of improving luminance and light extraction efficiency thereof while preventing image blur, and a method for manufacturing the same is disclosed. In accordance with the device and the method, image blur is suppressed and luminance and light-emitting efficiency are improved by forming micro-lenses on an encapsulating layer for protecting organic light-emitting elements at precise positions corresponding to the elements in a self-aligned and self-assembled manner.

First claim

What is claimed is:

1 . An organic light-emitting display device comprising:
a substrate; a plurality of organic light-emitting elements disposed on the substrate; an encapsulating layer covering the plurality of organic light-emitting elements; a first buffer layer disposed on the encapsulating layer, wherein the first buffer layer is hydrophilic; a second buffer layer disposed on the first buffer layer, wherein the second buffer layer is hydrophobic and has a plurality of openings, wherein each opening in the plurality of openings overlaps with a respective organic light-emitting element in the plurality of organic light-emitting elements and exposes a corresponding portion of the first buffer layer; and a plurality of micro-lenses, wherein each micro-lens is disposed on the exposed portion of the hydrophilic first buffer layer of a corresponding opening in the plurality of openings.

2 . The organic light-emitting display device of claim 1 , wherein the encapsulating layer includes an alternately laminated inorganic material layers and organic material layers.

3 . The organic light-emitting display device of claim 2 , wherein the encapsulating layer includes:
a first inorganic material layer covering the organic light-emitting element; an organic material layer disposed on the first inorganic material layer; and a second inorganic material layer disposed on the organic material layer, wherein the first buffer layer is disposed on the second inorganic material layer.

4 . The organic light-emitting display device of claim 1 , wherein each of the micro-lenses is made of a hydrophilic polymer.

5 . The organic light-emitting display device of claim 1 , wherein the second buffer layer includes a light-blocking material.

6 . The organic light-emitting display device of claim 1 , further comprising:
a bank layer disposed below the second buffer layer having a plurality of bank openings, wherein each bank opening defines an opening region of a respective organic light-emitting element by exposing at least a part of the respective organic light-emitting element, wherein an area of a bank opening in the plurality of bank openings in the bank layer is smaller than an area of an opening in the plurality of openings in the second buffer layer.

7 . The organic light-emitting display device of claim 1 , wherein the second buffer layer further has an opening pattern that connects a first opening in the plurality of openings with a second opening adjacent the first opening.

8 . The organic light-emitting display device of claim 1 , wherein a top surface of the second buffer layer is inclined.

9 . A method for manufacturing an organic light-emitting display device, the method comprising:
forming a plurality of organic light-emitting elements on a substrate; forming an encapsulating layer covering the plurality of organic light-emitting elements; forming a first buffer layer on the encapsulating layer, wherein the first buffer layer is hydrophilic; forming a second buffer layer on the first buffer layer, wherein the second buffer layer is hydrophobic and has a plurality of openings, wherein each opening in the plurality of openings overlaps with a respective organic light-emitting element in the plurality of organic light-emitting elements and exposes a corresponding portion of the first buffer layer; and applying a hydrophilic polymer onto the second buffer layer such that a plurality of micro-lenses are respectively formed on the exposed portions of the hydrophilic first buffer layer.

10 . The method of claim 9 , wherein the second buffer layer is made of a hydrophobic polymer including a light-blocking material.

11 . The method of claim 9 , wherein forming the plurality of organic light-emitting elements on the substrate includes:
forming a first electrode on the substrate; forming a bank layer on the first electrode, wherein the bank layer has a plurality of bank openings, wherein each bank opening exposes at least a part of the first electrode; forming a light-emitting layer on the exposed part of the first electrode; and forming a second electrode on the light-emitting layer.

12 . The method of claim 11 , wherein an area of a bank opening in the plurality of bank openings in the bank layer is smaller than an area of an opening in the plurality of openings in the second buffer layer.

13 . The method of claim 9 , wherein forming the second buffer layer further includes patterning the second buffer layer to form an opening pattern that connects a first opening in the plurality of openings with a second opening adjacent the first opening.

14 . The method of claim 9 , wherein forming the second buffer layer further includes forming the second buffer layer such that a top surface of the second buffer layer is inclined.

15 . An organic light-emitting display device comprising:
a substrate; a plurality of organic light-emitting elements disposed on the substrate; an encapsulating layer covering the plurality of organic light-emitting elements; a first buffer layer disposed on the encapsulating layer; a second buffer layer disposed on the first buffer layer, the second buffer layer having an opening with a first part of the second buffer layer and a second part of the second buffer layer separated from the first part of the second buffer layer, wherein the opening overlaps with a respective organic light-emitting element in the plurality of organic light-emitting elements and exposes a portion of the first buffer layer through the first part of the second buffer layer and the second part of the second buffer layer; and a micro-lens disposed within the opening between the first part of the second buffer layer and the second part of the second buffer layer.

16 . The organic light-emitting display device of claim 15 , wherein a surface of the first buffer layer is hydrophilic and a surface of the second buffer layer is hydrophobic.

17 . The organic light-emitting display device of claim 15 , wherein the micro-lens is made of a hydrophilic polymer.

18 . The organic light-emitting display device of claim 15 , wherein the second buffer layer includes a light-blocking material.

19 . The organic light-emitting display device of claim 15 , further comprising:
a bank layer disposed below the second buffer layer having a bank opening, wherein the bank opening defines an opening region of a respective organic light-emitting element by exposing at least a part of the respective organic light-emitting element, wherein an area of the bank opening in the bank layer is smaller than an area of the opening in the second buffer layer.

20 . The organic light-emitting display device of claim 15 , wherein the second buffer layer further has another opening that overlaps with another respective organic light-emitting element in the plurality of organic light-emitting elements, and wherein the second buffer layer has an opening pattern that connects the opening to the another opening.

21 . The organic light-emitting display device of claim 15 , wherein a top surface of the second buffer layer is inclined.

22 . The organic light-emitting display device of claim 15 , wherein a thickness of the second buffer layer at a first distance from an outer edge of the organic light-emitting display device is greater than a thickness of the second buffer layer at a second distance smaller than the first distance from the outer edge of the organic light-em

Assignees

• Lg Display Co Ltd

Inventors

• Lee Byungjoo
• Lee Youngbok
• Lee Keongjin
• Heo Taeyoung
• Lee Wonsik

Classifications

• H01L51/5256

  Electricity · mapped topic

• H01L27/3272

  Electricity · mapped topic

• H01L51/5275 Primary

  Electricity · mapped topic

• H01L27/3246

  Electricity · mapped topic

• H10K59/8791

  Arrangements for improving contrast, e.g. preventing reflection of ambient light · CPC title