Light-emitting device and display apparatus including the light-emitting device

Patent metadata

Field	Value
Publication number	US-10903454-B2
Application number	US-202016752067-A
Country	US
Kind code	B2
Filing date	Jan 24, 2020
Priority date	Jan 28, 2019
Publication date	Jan 26, 2021
Grant date	Jan 26, 2021

Abstract

A light-emitting device includes a metal reflection layer having a phase modulation surface, a color conversion layer provided on the phase modulation surface of the metal reflection layer, a first electrode provided on the color conversion layer, a hole injection and transport layer provided on the first electrode, a blue organic light-emitting layer provided on the hole injection and transport layer, an electron injection and transport layer provided on the blue organic light-emitting layer, and a second electrode provided on the electron injection and transport layer. The phase modulation surface of the metal reflection layer generates magnetic resonance with respect to incident light. The color conversion layer includes a photoluminescent material.

First claim

What is claimed is:

1. A light-emitting device comprising:
a first metal reflection layer comprising a first phase modulation surface, the first phase modulation surface being configured to generate magnetic resonance with respect to light that is incident upon the first phase modulation surface;
a color conversion layer provided on the first phase modulation surface and comprising a photoluminescent material;
a first electrode provided on the color conversion layer;
a hole injection and transport layer provided on the first electrode;
a blue organic light-emitting layer provided on the hole injection and transport layer;
an electron injection and transport layer provided on the blue organic light-emitting layer; and
a second electrode provided on the electron injection and transport layer.

2. The light-emitting device of claim 1 , wherein the first metal reflection layer and the second electrode form a microcavity having a resonant wavelength.

3. The light-emitting device of claim 1 , wherein the first phase modulation surface has a meta structure in which nano patterns are arranged periodically.

4. The light-emitting device of claim 1 , wherein the color conversion layer comprises a dielectric in which the photoluminescent material is dispersed.

5. The light-emitting device of claim 4 , wherein the photoluminescent material comprises at least one of quantum dots, an organic fluorescent dye, an organic fluorescent semiconductor, and an organic phosphorescent semiconductor.

6. The light-emitting device of claim 1 , wherein the photoluminescent material comprises a green photoluminescent material configured to convert blue light into green light or a red photoluminescent material configured to convert blue light into red light.

7. The light-emitting device of claim 1 , wherein the color conversion layer contacts an entirety of the first phase modulation surface of the first metal reflection layer.

8. The light-emitting device of claim 1 , further comprising:
a transparent planarization layer between the first metal reflection layer and the color conversion layer to cover the first phase modulation surface of the first metal reflection layer.

9. The light-emitting device of claim 1 , wherein the first electrode comprises a transparent electrode, and
wherein the second electrode comprises a transflective electrode that transmits a first part of light that is incident upon the second electrode and reflects a second part of the light that is incident upon the second electrode.

10. The light-emitting device of claim 1 , wherein the first electrode comprises a transparent electrode and the second electrode comprises a reflective electrode, and
wherein the first metal reflection layer is semi-transparent and is configured to transmit a first part of light that is incident upon the first metal reflection layer and to reflect a second part of the light that is incident upon the first metal reflection layer.

11. The light-emitting device of claim 1 , further comprising:
a second metal reflection layer provided on the second electrode and comprising a second phase modulation surface; and
a planarization layer provided between the second electrode and the second metal reflection layer to cover the second phase modulation surface of the second metal reflection layer.

12. The light-emitting device of claim 11 , wherein the first metal reflection layer and the second metal reflection layer form a microcavity having a resonant wavelength.

13. The light-emitting device of claim 11 , wherein the first electrode comprises a first transparent electrode and the second electrode comprises a second transparent electrode,
wherein one of the first metal reflection layer and the second metal reflection layer is reflective with respect to light that is incident upon the one of the first metal reflection layer and the second metal reflection layer, and
wherein the other of the first metal reflection layer and the second metal reflection layer is semi-transparent and configured to transmit a first part of light that is incident upon the other of the first metal reflection layer and the second metal reflection layer and to reflect a second part of the light that is incident upon the other of the first metal reflection layer and the second metal reflection layer.

14. A display apparatus comprising:
a plurality of pixels configured to emit light rays of different colors,
wherein at least one pixel from among the plurality of pixels comprises:
a first metal reflection layer comprising a first phase modulation surface, the first phase modulation surface being configured to generate magnetic resonance with respect to light that is incident upon the first phase modulation surface;
a color conversion layer provided on the first phase modulation surface and comprising a photoluminescent material;
a first electrode provided on the color conversion layer;
a hole injection and transport layer provided on the first electrode;
a blue organic light-emitting layer provided on the hole injection and transport layer;
an electron injection and transport layer provided on the blue organic light-emitting layer; and
a second electrode provided on the electron injection and transport layer.

15. The display apparatus of claim 14 , wherein the first phase modulation surface comprises a meta structure in which nano patterns are arranged periodically.

16. The display apparatus of claim 14 , wherein the color conversion layer contacts an entirety of the first phase modulation surface of the first metal reflection layer.

17. The display apparatus of claim 14 , wherein the at least one pixel further comprises a transparent planarization layer between the first metal reflection layer and the color conversion layer to cover the first phase modulation surface of the first metal reflection layer.

18. The display apparatus of claim 14 , wherein the at least one pixel further comprises:
a second metal reflection layer provided on the second electrode and comprising a second phase modulation surface; and
a planarization layer provided between the second electrode and the second metal reflection layer to cover the second phase modulation surface of the second metal reflection layer.

19. The display apparatus of claim 14 , wherein the plurality of pixels comprise a blue pixel, a green pixel, and a red pixel.

20. The display apparatus of claim 19 , wherein the green pixel comprises a green photoluminescent material configured to convert blue light into green light, and
wherein the red pixel comprises a red photoluminescent material configured to convert blue light into red light.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Joo Wonjae
• Kyoung Jisoo

Classifications

• H10K59/878

  comprising reflective means · CPC title

• H10K59/876

  comprising a resonant cavity structure, e.g. Bragg reflector pair · CPC title

• H10K50/852

  comprising a resonant cavity structure, e.g. Bragg reflector pair · CPC title

• H10K59/38 Primary

  comprising colour filters or colour changing media [CCM] · CPC title

• H10K50/125 Primary

  specially adapted for multicolour light emission, e.g. for emitting white light · CPC title