Display device

Patent metadata

Field	Value
Publication number	US-9692001-B2
Application number	US-201514838495-A
Country	US
Kind code	B2
Filing date	Aug 28, 2015
Priority date	Sep 1, 2014
Publication date	Jun 27, 2017
Grant date	Jun 27, 2017

Abstract

The display device includes a first organic electroluminescence element which includes an anode and a cathode which form a pair, and a light emitting layer which is formed between the anode and the cathode on a substrate. The light emitting layer includes a plurality of sub-light emitting layers which perform light emitting of colors which are respectively different. Each of the plurality of sub-light emitting layers is doped with a quantum dot light emitting material corresponding to a color to be emitted. A current with current density corresponding to a position of a sub-light emitting layer of a desired color among the plurality of sub-light emitting layers is injected to the light emitting layer, and the sub-light emitting layer of the desired color performs light emitting.

First claim

What is claimed is:

1. A display device comprising:
a first organic electroluminescence element, including:
an anode and a cathode which form a pair;
a light emitting layer which is formed between the anode and the cathode on a substrate, the light emitting layer including a plurality of sub-light emitting layers which are stacked along a stacking direction from the anode to the cathode, the plurality of sub-light emitting layers configured to perform light emitting of colors which are respectively different according to a position along the stacking direction due to recombination of a hole and an electron depending on a current density of a current flowing in the light emitting layer, each of the plurality of sub-light emitting layers being doped with a quantum dot light emitting material corresponding to a color to be emitted; and
a bank which surrounds the anode for pixel separation; and

a voltage line, providing a voltage for controlling the current density of the current flowing in the light emitting layer,
wherein the current with current density corresponding to a position along the stacking direction of a sub-light emitting layer of a desired color among the plurality of sub-light emitting layers is injected to the light emitting layer, and the sub-light emitting layer of the desired color performs light emitting, and
wherein the plurality of sub-light emitting layers are formed covering the anode and the bank.

2. The display device according to claim 1 ,
wherein the plurality of sub-light emitting layers are stacked along the stacking direction in order of high light emitting efficiency with respect to predetermined current density from the anode to the cathode.

3. The display device according to claim 1 , further comprising:
a second organic electroluminescence element which is close to the first organic electroluminescence element, and performs white light emitting,
wherein one pixel is formed of the first organic electroluminescence element and the second organic electroluminescence element.

4. The display device according to claim 1 ,
wherein the plurality of sub-light emitting layers include three layers.

5. The display device according to claim 4 ,
wherein the three layers are for emitting red light, green light, and blue light, respectively.

6. The display device according to claim 5 ,
wherein the three layers overlap the bank.

Assignees

• Japan Display Inc

Inventors

• Toyoda Hironori
• Sato Toshihiro

Classifications

• H01L51/502

  Electricity · mapped topic

• H01L27/3206

  Electricity · mapped topic

• H01L51/504 Primary

  Electricity · mapped topic

• H10K59/30 Primary

  Devices specially adapted for multicolour light emission · CPC title

• H10K50/115

  comprising active inorganic nanostructures, e.g. luminescent quantum dots · CPC title