Nanostructure based display devices

1. A display device comprising:

a backlight unit comprising a light source; and

a liquid crystal display (LCD) module comprising:

a phosphor film configured to receive a primary light, from the light source, having a first peak wavelength and to convert a portion of the primary light to emit a secondary light having a second peak wavelength that is different from the first peak wavelength; and

a filter element comprising nanostructured materials that exhibit light absorption properties and do not exhibit luminescent properties, wherein the filter element is optically coupled to the phosphor film and is configured to allow the secondary light to pass through the filter element and to block an unconverted portion of the primary light from passing through the filter element.

2. The display device of claim 1 , wherein the nanostructured materials are configured to absorb the unconverted portion of the primary light.

3. The display device of claim 1 , wherein the nanostructured materials are configured to scatter the unconverted portion of the primary light.

4. The display device of claim 1 , wherein:

the phosphor film comprises a matrix; and

the filter element is embedded in the matrix.

5. The display device of claim 1 , wherein the filter element comprises a non-phosphor based material.

6. The display device of claim 1 , wherein the filter element comprises a dye, ink, paint, or polymeric material.

7. The display device of claim 1 , wherein the filter element comprises a scattering material.

8. The display device of claim 1 , wherein the filter element comprises scattering particles having titanium oxide, zinc oxide, zinc sulfide, silicone, or a combination thereof.

9. The display device of claim 1 , wherein the phosphor film comprises luminescent nanostructures.

10. The display device of claim 1 , wherein the phosphor film comprises an array of segmented phosphor films.

11. The display device of claim 1 , wherein:

the phosphor film comprises an array of phosphor films;

at least one of the phosphor films of the array comprises a first population of luminescent nanostructures configured to emit red light; and

at least one of the phosphor films of the array comprises a second population of luminescent nanostructures configured to emit green light.

12. The display device of claim 1 , wherein the phosphor film comprises:

a first region having a first population of luminescent nanostructures configured to emit red light; and

a second region having a second population of luminescent nanostructures configured to emit green light.

13. The display device of claim 1 , wherein:

the phosphor film comprises an array of phosphor films;

at least one of the phosphor films of the array comprises a first population of luminescent nanostructures configured to emit red light; and

at least one of the phosphor films of the array comprises a second population of luminescent nanostructures configured to emit green light; and

at least one of the phosphor films of the array comprises a third population of luminescent nanostructures configured to emit blue light.

14. The display device of claim 1 , wherein the phosphor film comprises:

a first region having a first population of luminescent nanostructures configured to emit red light;

a second region having a second population of luminescent nanostructures configured to emit green light; and

a third region having a third population of luminescent nanostructures configured to emit blue light.

15. The display device of claim 1 , wherein the LCD module further comprises:

a first polarizing filter configured to polarize the primary light;

a liquid crystal solution layer configured to adjust an angle of polarization of the polarized primary light; and

a second polarizing filter, disposed between the phosphor film and the liquid crystal solution layer, configured to control transmission of the polarized primary light from the liquid crystal solution layer to the phosphor film.

16. The display device of claim 1 , wherein the filter element is further configured to tune a spectral emission width of the secondary light to adjust color gamut coverage of a standard RGB color space.

17. The display device of claim 1 , wherein the filter element is further configured to tune a spectral emission width of the secondary light to achieve over 90% color gamut coverage of a standard RGB color space.

18. The display device of claim 17 , wherein the standard RGB color space is Rec. 2020 color space.

19. The display device of claim 1 , wherein the filter element is further configured to tune the spectral emission width of the secondary light to achieve over 90% color gamut coverage of Rec. 2020 color space with less than 10% decrease in brightness level of the display device.

20. The display device of claim 1 , further comprising an optical cavity, wherein the light source is positioned within the optical cavity.

21. The display device of claim 1 , further comprising a light guide plate, wherein the light source is externally coupled to the light guide plate.

22. A display device comprising:

an organic light emitting diode (OLED);

a phosphor film configured to receive a primary light, from the OLED, having a first peak wavelength and to convert a portion of the primary light to emit a secondary light having a second peak wavelength that is different from the first peak wavelength; and

a filter element comprising nanostructured materials that exhibit light absorption properties and do not exhibit luminescent properties, wherein the filter element is optically coupled to the phosphor film and is optically coupled to the phosphor film and is configured to allow the secondary light to pass through the filter element and to block an unconverted portion of the primary light from passing through the filter element.

23. The display device of claim 22 , wherein the OLED, the phosphor film, and the filter element are parts of a pixel of the display device.

24. The display device of claim 22 , wherein the nanostructured materials are configured to absorb the unconverted portion of the primary light.

25. The display device of claim 22 , wherein the nanostructured materials are configured to scatter the unconverted portion of the primary light.

26. The display device of claim 22 , wherein:

the phosphor film comprises a matrix; and

the filter element is embedded in the matrix.

27. The display device of claim 22 , wherein the filter element comprises a non-phosphor based material.

28. The display device of claim 22 , wherein the filter element comprises a dye, ink, paint, or polymeric material.

29. The display device of claim 22 , wherein the filter element comprises a scattering material.

30. The display device of claim 22 , wherein the filter element comprises scattering particles having titanium oxide, zinc oxide, zinc sulfide, silicone, or a combination thereof.

31. The display device of claim 22 , wherein the phosphor film comprises luminescent nanostructures.

32. The display device of claim 22 , wherein the phosphor film is disposed on the OLED.

33. The display device of claim 22 , wherein the phosphor film comprises a population of luminescent nanostructures configured to emit red light.

34. The display device of claim 22 , wherein the phosphor film comprises a population of luminescent nanostructures configured to emit green light.

35. The display device of claim 22 , wherein the phosphor film comprises a population of luminescent nanostructures configured to emit blue light.

36. The display device of claim 22 , comprising first and second phosphor films, wherein:

the first phosphor film comprises a first population of luminescent nanostructures configured to emit red light; and

the second phosphor film comprises a second population of luminescent nanostructures configured to emit green light.

37. The display device of claim 36 , comprising first and second filter elements, wherein:

the first filter element is disposed on the first phosphor film and is part of a red sub-pixel; and

the second filter element is disposed on the second phosphor film and is part of a green sub-pixel.

38. The display device of claim 22 , comprising first, second, and third phosphor films, wherein:

the first phosphor film comprises a first population of luminescent nanostructures configured to emit red light;

the second phosphor film comprises a second population of luminescent nanostructures configured to emit green light; and

the third phosphor film comprises a third population of luminescent nanostructures configured to emit blue light.

39. The display device of claim 38 , comprising first, second, and third filter elements, wherein:

the first filter element is disposed on the first phosphor film and is part of a red sub-pixel;

the second filter element is disposed on the second phosphor film and is part of a green sub-pixel; and

the third filter element is disposed on the third phosphor film and is part of a blue sub-pixel.

40. A display device comprising an array of pixels, a pixel of the array of the pixels comprising:

a sub-pixel having:

a quantum dot (QD) film configured to receive a primary light having a first peak wavelength and to convert a portion of the primary light to emit a secondary light having a second peak wavelength that is different from the first peak wavelength, wherein the QD film comprises QDs disposed in a polymeric matrix; and

a filter element configured to allow the secondary light to pass through the filter element and to block an unconverted portion of the primary light from passing through the filter element, wherein the filter element comprises nanostructured non-phosphor materials that exhibit light absorption properties and do not exhibit luminescent properties are disposed in the polymeric matrix.

41. The display device of claim 40 , wherein the pixel comprises:

a first sub-pixel comprising a first QD film having a first population of QDs configured to emit red light;

a second sub-pixel comprising a second QD film having a second population of QDs configured to emit green light; and

a third sub-pixel comprising a third QD film having a third population of QDs configured to emit blue light.

42. The display device of claim 40 , wherein the pixel comprises:

a first sub-pixel comprising a first QD film configured to emit red light and a first filter element;

a second sub-pixel comprising a second QD film configured to emit green light and a second filter element; and

a third sub-pixel comprising first and second films that are optically transmissive to the primary light and are configured to pass the primary light through the first and second films without down conversion.

43. The display device of claim 40 , wherein the pixel further comprises a light emitting diode.