Transparent luminescent displays enabled by electric-field-induced quenching of photoluminescent pixels

Patent metadata

Field	Value
Publication number	US-10680194-B2
Application number	US-201614993399-A
Country	US
Kind code	B2
Filing date	Jan 12, 2016
Priority date	Jan 12, 2015
Publication date	Jun 9, 2020
Grant date	Jun 9, 2020

Abstract

A light emitting device can include a light source, a first electrode, a second electrode, a first barrier layer, a second barrier layer, and an emitter layer between the first barrier layer and the second barrier layer. A method of controllably generating light can comprise two states: An ON state, wherein an emitter layer of a device (which includes a photoluminescent pixel) is illuminated with a light source in the absence of an electric field, and the emitter layer generates light through photoluminescence; and an OFF state, wherein an emitter layer of a device (which includes a photoluminescent pixel) is illuminated with a light source in the presence of a static or time-varying electric field, and the electric field or induced current results in quenching of the emitter photoluminescence.

First claim

What is claimed is:

1. A light emitting device comprising:
a light source;
a first electrode;
a second electrode;
a first barrier layer;
a second barrier layer; wherein the first barrier layer and the second barrier layer are between the first electrode and the second electrode, and
an emitter layer between the first barrier layer and the second barrier layer,
wherein the emitter layer includes a photoluminescent pixel capable of being excited by the light source;
wherein at least one of the first barrier layer and the second barrier layer is transparent, and at least one of the first electrode and the second electrode is transparent and wherein indexes of refraction of the first electrode, the second electrode, the first barrier layer, the second barrier layer, and the emitter layer at a wavelength of the light source are similar to enable a majority of an excitation light to impinge upon and be absorbed by the emitter layer rather than staying confined to a substrate, and the emitter layer includes a quantum confined nanostructured material.

2. The light emitting device of claim 1 , wherein indexes of refraction of the first electrode, the second electrode, the first barrier layer, the second barrier layer, and the emitter layer at a wavelength of the light source are within 30% of each other.

3. The light emitting device of claim 1 , wherein the emitter layer includes a plurality of photoluminescent pixels.

4. The light emitting device of claim 1 , wherein the emitter layer includes photoluminescent pixels of different colors.

5. The light emitting device of claim 1 , wherein the emitter includes a red photoluminescent pixel, a green photoluminescent pixel, and a blue photoluminescent pixel.

6. The light emitting device of claim 1 further comprising a substrate, wherein the substrate is transparent.

7. The light emitting device of claim 1 , wherein both the first electrode and the second electrode are transparent.

8. The light emitting device of claim 1 , wherein both the first barrier layer and the second barrier layer are transparent.

9. The light emitting device of claim 1 , wherein the first electrode or the second electrode is opaque.

10. The light emitting device of claim 1 , wherein the first barrier layer or the second barrier layer is opaque.

11. The light emitting device of claim 1 , wherein the emitter layer has a thickness of less than 100 nm.

Assignees

• Massachusetts Inst Technology

Inventors

• Brown Patrick R
• Supran Geoffrey J
• Grossman Jeffrey C
• Bawendi Moungi G
• Bulovic Vladimir

Classifications

• H01L51/502 Primary

  Electricity · mapped topic

• H01L51/52

  Electricity · mapped topic

• H10K59/80

  Constructional details · CPC title

• H10K50/80

  Constructional details · CPC title

• H10K50/115 Primary

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