Electronic displays using optically pumped luminescent semiconductor nanocrystals

• US 8,648,524 B2
• Filed: 08/17/2011
• Issued: 02/11/2014
• Est. Priority Date: 06/03/1998
• Status: Expired due to Fees

• Current Assignee: Regents of the University of California (University of California)
• Original Assignee: Regents of the University of California (University of California)
• Inventors: Weiss, Shimon, Schlamp, Michael C., Alivisatos, A. Paul
• Primary Examiner(s): Mai, Anh
• Assistant Examiner(s): QUARTERMAN, KEVIN J
• Application Number:
  US13/211,664
• Publication Number:
  US 20110299011A1
• Time in Patent Office: 909 Days
• Field of Search: 313485-486, 313467-468, 313/496, 313/503, 252/586, 252/588
• US Class Current: 313/503
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: G02B 5/207 comprising semiconducting materials
• CPC Class Codes: G02F 1/1333 Constructional arrangements; Manufacturing methodsG02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/133362 Optically addressed liquid crystal cells G02F1/135 takes precedence
• CPC Class Codes: G02F 1/133509 Filters, e.g. light shielding masks
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/133617 Illumination with ultraviolet light; Luminescent elements or materials associated to the cell
• CPC Class Codes: G02F 2202/36 Micro- or nanomaterials
• CPC Class Codes: H10K 2102/331 Nanoparticles used in non-emissive layers, e.g. in packaging layer
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 59/35 comprising red-green-blue [RGB] subpixels

Abstract

A multicolor electronic display is based on an array of luminescent semiconductor nanocrystals. Nanocrystals which emit light of different colors are grouped into pixels. The nanocrystals are optically pumped to produce a multicolor display. Different sized nanocrystals are used to produce the different colors. A variety of pixel addressing systems can be used.

Claims

1. A color display apparatus comprising:

an optical pumping source comprising one or more blue LED'"'"'s;

a transparent plate; and

a layer of quantum dots, said quantum dots emitting light in response to exposure to light from said optical pumping source;

wherein said layer of quantum dots is positioned between said optical pumping source and said transparent plate.

2. The apparatus of claim 1, wherein said quantum dots comprise material selected from the group of cadmium selenide (CdSe), cadmium sulfide (CdS), indium arsenide (InAs), and indium phosphide (InP).

3. The apparatus of claim 1, wherein said quantum dots comprise material selected from the group of zinc selenide (ZnSe) and zinc sulfide (ZnS).

4. The apparatus of claim 1, further comprising a long pass filter in operative association with the layer of quantum dots.

5. The optical pumping source of claim 1, further comprising a polarizer positioned between the optical pumping source and the liquid crystal modulator transparent plate.

6. The apparatus of claim 1, wherein the layer of quantum dots is formed of nanocrystals which emit green and red light.

7. The apparatus of claim 1, wherein the layer of quantum dots is formed of nanocrystals which emit at least one of blue, green and/or red light.

8. The apparatus of claim 1, wherein the layer of quantum dots comprises a plurality of nanocrystals embedded in a polymer film.

9. The apparatus of claim 1, further comprising a filter placed over the layer of quantum dots.

10. The apparatus of claim 1, wherein said transparent plate comprises glass.

11. The apparatus of claim 1, wherein the layer of quantum dots is positioned on the optical pumping source.

12. The apparatus of claim 1, wherein the optical pumping source comprises a waveguide.

13. The apparatus of claim 12, wherein the waveguide is end pumped by a pump source that emits light along a lateral side of the pump source.

14. A color display apparatus comprising:

an optical pumping source;

a transparent plate; and

a layer of quantum dots, said quantum dots emitting light in response to exposure to light from said optical pumping source;

wherein said layer of quantum dots is positioned between said optical pumping source and said transparent plate, and

wherein said color display is configured to display dynamic color images.

15. The apparatus of claim 14, wherein said quantum dots comprise material selected from the group of cadmium selenide (CdSe), cadmium sulfide (CdS), indium arsenide (InAs), and indium phosphide (InP).

16. The apparatus of claim 14, wherein said quantum dots comprise material selected from the group of zinc selenide (ZnSe) and zinc sulfide (ZnS).

17. The apparatus of claim 14, further comprising a long pass filter in operative association with the layer of quantum dots.

18. The apparatus of claim 14, wherein the optical pumping source comprises a source of ultraviolet or blue light.

19. The apparatus of claim 14, wherein the optical pumping source comprises one or more blue LED'"'"'s.

20. The optical pumping source of claim 14, further comprising a polarizer positioned between the optical pumping source and the transparent plate.

21. The apparatus of claim 14, wherein the layer of quantum dots is formed of nanocrystals which emit green and red light.

22. The apparatus of claim 14, wherein the layer of quantum dots is formed of nanocrystals which emit at least one of blue, green and/or red light.

23. The apparatus of claim 14, wherein the layer of quantum dots comprises a plurality of nanocrystals embedded in a polymer film.

24. The apparatus of claim 14, further comprising a filter placed over the layer of quantum dots.

25. The apparatus of claim 14, wherein said transparent plate comprises glass.

26. The apparatus of claim 14, wherein the layer of quantum dots is positioned on the optical pumping source.

27. The apparatus of claim 14, wherein the optical pumping source comprises a waveguide.

28. The apparatus of claim 27, wherein the waveguide is end pumped by a pump source that emits light along a lateral side of the pump source.