Quantum dot light emitting device and optical apparatus including the same

Patent metadata

Field	Value
Publication number	US-2018102093-A1
Application number	US-201715450128-A
Country	US
Kind code	A1
Filing date	Mar 6, 2017
Priority date	Oct 11, 2016
Publication date	Apr 12, 2018
Grant date	—

Abstract

A quantum dot light emitting device includes a grating device which includes a grating region that has a particular grating interval, and a quantum dot layer located above the grating region. The device provides high-purity color light based on a selection of a wavelength band by the grating region in correspondence with a wavelength band of light emitted from the quantum dot layer.

First claim

What is claimed is:

1 . A quantum dot light emitting device comprising:
a grating device comprising a first grating region that has a first grating interval, and a second grating region that has a second grating interval which is different from the first grating interval; and an emission layer located above the grating device and comprising a first quantum dot layer configured to emit light of a wavelength band which is selected by the first grating region.

2 . The quantum dot light emitting device of claim 1 , further comprising a first electrode and a second electrode which are arranged such that the first quantum dot layer is located between the first electrode and the second electrode.

3 . The quantum dot light emitting device of claim 2 , wherein the first electrode, the first quantum dot layer, and the second electrode are successively stacked in a direction that is perpendicular to a direction of the first grating interval.

4 . The quantum dot light emitting device of claim 2 , further comprising:
a hole transport layer located between the first quantum dot layer and the first electrode; and an electron transport layer located between the first quantum dot layer and the second electrode.

5 . The quantum dot light emitting device of claim 1 , wherein the first grating region comprises a plurality of strip-shaped protruding patterns.

6 . The quantum dot light emitting device of claim 1 , wherein the first grating region comprises a plurality of pillar-shaped protruding patterns or groove patterns.

7 . The quantum dot light emitting device of claim 5 , wherein spaces between the protruding patterns are filled with a material that has a refractive index which is different from a refractive index of the grating device.

8 . The quantum dot light emitting device of claim 1 , further comprising a pump light source configured to provide exciting light to the emission layer.

9 . The quantum dot light emitting device of claim 1 , wherein the grating device further comprises at least a third grating region that has a third grating interval which is different from each of the first grating interval and the second grating interval.

10 . The quantum dot light emitting device of claim 9 , wherein the emission layer further comprises:
a second quantum dot layer which is arranged to face the second grating region and is configured to emit light of a wavelength band selected by the second grating region; and a third quantum dot layer which is arranged to face the third grating region and is configured to emit light of a wavelength band selected by the third grating region.

11 . The quantum dot light emitting device of claim 9 , wherein the first quantum dot layer is arranged to face all of the first grating region, the second grating region, and the third grating region.

12 . The quantum dot light emitting device of claim 11 , wherein the first quantum dot layer is configured to emit light of a plurality of wavelength bands including a first wavelength band selected by the first grating region, a second wavelength band selected by the second grating region, and a third wavelength band selected by the third grating region.

13 . The quantum dot light emitting device of claim 11 , wherein the first quantum dot layer comprises a plurality of quantum dots that has at least three different quantum dot sizes.

14 . The quantum dot light emitting device of claim 1 , wherein the grating device is made of a dielectric material.

15 . The quantum dot light emitting device of claim 1 , wherein the grating device is made of a conductive material.

16 . The quantum dot light emitting device of claim 15 , further comprising an electrode which is disposed above the first quantum dot layer,
wherein when a voltage is applied between the electrode and the grating device, the applied voltage causes an emission of light from the emission layer.

17 . A display apparatus comprising:
a grating device comprising a first grating region that has a first grating interval, a second grating region that has a second grating interval which is different from the first grating interval, and a third grating region that has a third grating interval which is different from each of the first grating interval and the second grating interval; an emission layer located above the grating device and comprising a first quantum dot layer that is arranged to face the first grating region, a second quantum dot layer that is arranged to face the second grating region, and a third quantum dot layer that is arranged to face the third grating region; a first electrode that is arranged to face the emission layer; and a plurality of second electrodes, each respective second electrode being arranged to face a corresponding one from among the first quantum dot layer, the second quantum dot layer, and the third quantum dot layer.

18 . The display apparatus of claim 17 , further comprising a driving circuit layer comprising a plurality of transistors, each respective transistor being configured to provide a respective electrical signal to a corresponding one from among the plurality of second electrodes in order to control an emission of light from the first quantum dot layer, the second quantum dot layer, and the third quantum dot layer.

19 . An optical sensor comprising:
the quantum dot light emitting device of claim 1 which is configured to irradiate light toward an object; and a sensor component configured to receive light reflected from the object.

20 . The optical sensor of claim 19 , wherein the emission layer further comprises a second quantum dot layer that is arranged to face the second grating region and is configured to emit light of a wavelength band selected by the second grating region.

21 . The optical sensor of claim 19 , wherein the first quantum dot layer is arranged to face both of the first grating region and the second grating region.

22 . The optical sensor of claim 21 , wherein the first quantum dot layer is configured to emit light of a plurality of wavelength bands which includes a first wavelength band selected by the first grating region, and a second wavelength band selected by the second grating region.

23 . A quantum dot light emitting device comprising:
a grating device comprising a first grating region that has a first grating interval, and at least a second grating region that has a second grating interval which is different from the first grating interval; and a first electrode disposed above the grating device; a quantum dot layer disposed above the first electrode and configured to emit light of a plurality of wavelengths; and a second electrode disposed above the quantum dot layer, wherein the plurality of wavelengths includes a first wavelength that corresponds to the first grating region and a second wavelength that corresponds to the second grating region.

24 . The quantum dot light emitting device of claim 23 , wherein the quantum dot layer is stacked on top of the first electrode and the second electrode is stacked on top of the quantum dot layer.

25 . The quantum dot light emitting device of claim 23 , further comprising a hole transport layer disposed between the first electrode and the quantum dot layer and an electron transport layer disposed between the quantum dot layer, such that the first electrode, the hole transport layer, the quantum dot layer, the electron transport

Assignees

• Samsung Electronics Co Ltd

Inventors

• Kim Hyochul
• Park Yeonsang
• Cho Kyungsang
• KOH Weonkyu
• Roh Younggeun

Classifications

• G02B27/425

  in illumination systems (mask illumination systems in photolithographic systems G03F7/70158) · CPC title

• G02B27/4244

  in wavelength selecting devices (spectrometry G01J) · CPC title

• G09G2300/0426

  Layout of electrodes and connections · CPC title

• G01J1/08

  Arrangements of light sources specially adapted for photometry {standard sources, also using luminescent or radioactive material} · CPC title

• G09G2320/0626

  for control of overall brightness · CPC title