ELECTRONIC DISPLAYS USING OPTICALLY PUMPED LUMINESCENT SEMICONDUCTOR NANOCRYSTALS

• US 20110299011A1
• Filed: 08/17/2011
• Published: 12/08/2011
• Est. Priority Date: 06/03/1998
• Status: Active Grant

• 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
• Granted Patent: US 8,648,524 B2
• Time in Patent Office: Days
• US Class Current: 349/62
• 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

1-20. -20. (canceled)

21. A color display apparatus comprising:

an optical pumping source; and

a liquid crystal modulator; 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 liquid crystal modulator.

22. The apparatus of claim 21, wherein said quantum dots comprise material selected from the group of cadmium selenide (CdSe), cadmium sulfide (CdS), indium arsenide (InAs), and indium phosphide (InP).

23. The apparatus of claim 21, wherein said quantum dots comprise material selected from the group of zinc selenide (ZnSe) and zinc sulfide (ZnS).

24. The apparatus of claim 21, further comprising a long pass filter in operative association with the layer of quantum dots.

25. The apparatus of claim 21, wherein the optical pumping source comprises a source of ultraviolet or blue light.

26. The apparatus of claim 25, wherein the optical pumping source comprises one or more blue LED'"'"'s.

27. The apparatus of claim 21, further comprising an analyzer positioned between the optical pumping source and the liquid crystal modulator.

28. The optical pumping source of claim 21, further comprising a polarizer positioned between the optical pumping source and the liquid crystal modulator.

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

30. The apparatus of claim 21, wherein the layer of nanocrystals is formed of nanocrystals which emit at least one of blue, green and/or red light.

31. The apparatus of claim 21, wherein the layer of nanocrystals comprises a plurality of nanocrystals embedded in a polymer film.

32. The apparatus of claim 21, further comprising a filter placed over the layer of nanocrystals.

33. The apparatus of claim 21, wherein the layer of nanocrystals is formed on a transparent plate and the transparent plate is positioned between the layer of nanocrystals and the optical pumping source.

34. The apparatus of claim 21, wherein the layer of nanocrystals is formed on a transparent plate and the layer of nanocrystals is positioned between the transparent plate and the optical pumping source.

35. The apparatus of claim 33, wherein said plate comprises glass.

36. The apparatus of claim 34, wherein said plate comprises glass.

37. The apparatus of claim 21, wherein the layer of nanocrystals is positioned on the optical pumping source.

38. The apparatus of claim 21, wherein the optical pumping source comprises a waveguide

39. The apparatus of claim 38, wherein the waveguide is end pumped by a pump source that emits light along a lateral side of the pump source.