PHOTOLUMINESCENCE COLOR DISPLAY

• US 20120287381A1
• Filed: 02/23/2012
• Published: 11/15/2012
• Est. Priority Date: 07/06/2006
• Status: Active Grant

• Current Assignee: Intematix Corporation
• Original Assignee: Intematix Corporation
• Inventors: Li, Yi-Qun, Dong, Yi, Shan, Wei
• Granted Patent: US 8,947,619 B2
• Time in Patent Office: Days
• US Class Current: 349/106
• CPC Class Codes: G02F 1/133509 Filters, e.g. light shielding masks
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133567 on the back side
• CPC Class Codes: G02F 1/133614 using photoluminescence, e.g. phosphors illuminated by UV or blue light
• CPC Class Codes: G02F 1/133617 Illumination with ultraviolet light; Luminescent elements or materials associated to the cell
• CPC Class Codes: G02F 2203/02 reflective
• CPC Class Codes: G02F 2203/055 wavelength filtering
• CPC Class Codes: G02F 2203/34 Colour display without the use of colour mosaic filters

Abstract

A photoluminescence color display comprises a display panel that displays red, green and blue pixel areas, an excitation source operable to generate excitation radiation for operating the display, and a photoluminescence color-element plate. The color-element plate comprises at least one photoluminescence material, such as a phosphor material or quantum dots, that is operable to emit light corresponding to red, green and blue pixel areas of the display in response to said excitation radiation. Additionally, the photo-luminescence color display comprises a wavelength selective filter that is provided between the color-element plate and the excitation source. The filter has a transmission characteristic that allows the passage of excitation radiation from the excitation source to excite the at least one photoluminescence material whilst preventing the passage of photoluminescence light back to the excitation source thereby prevent cross contamination of light among the different pixel areas of the display.

Claims

1. A photoluminescence color display comprising:

a display panel comprising a plurality of red, green and blue pixel areas;

an excitation source operable to generate excitation radiation for operating the display;

a photoluminescence color-elements plate comprising at least one of;

a first photoluminescence material corresponding to red pixel areas of the display that is operable to emit red light in response to said excitation radiation;

a second photoluminescence material corresponding to green pixel areas of the display that is operable to emit green light in response to said excitation radiation; and

a third photoluminescence material corresponding to blue pixel areas of the display that is operable to emit blue light in response to said excitation radiation; and

a wavelength selective filter disposed between the color-element plate and the excitation source, the wavelength selective filter having a characteristic that allows the passage of excitation radiation and substantially prevents the passage of light generated by the photoluminescence materials.

2. The color display of claim 1, wherein the wavelength selective filter is substantially reflective to light generated by the photoluminescence materials.

3. The color display of claim 1, wherein the wavelength selective filter is configured to have a critical wavelength that is longer than the wavelength of the excitation radiation but shorter than the wavelength of light generated by said photoluminescence materials.

4. The color display of claim 1, wherein the wavelength selective filter comprises a dichroic filter.

5. The color display of claim 1, and further comprising a color filter plate located on a side the display panel that is distal to the excitation source, wherein the color filter plate comprises at least one of:

first filter areas corresponding to red pixel areas of the display that are operable to allow the passage of red light;

second filter areas corresponding to green pixel areas of the display that are operable to allow the passage of green light; and

third filter areas corresponding to blue pixel areas of the display that are operable to allow the passage of blue light.

6. The color display of claim 1, wherein the photoluminescence material is selected from the group consisting of:

an inorganic phosphor material, an organic phosphor material, a quantum dots material; and

combinations thereof.

7. The color display of claim 1, and further comprising:

a liquid crystal disposed between front and back plates of the display panel; and

a matrix of electrodes defining red, green and blue pixel areas of the display and operable to selectively induce an electric field across the liquid crystal in the pixel areas for controlling transmission of light through the pixels areas.

8. The color display of claim 7, wherein the photoluminescence materials are provided on either a lower face or an upper face of the back plate.

9. The color display of claim 1, wherein the excitation radiation is selected from the group consisting of:

UV light having a wavelength in a range 360 nm to 400 nm generated by at least one LED;

blue light having a wavelength in a range of 400 nm to 480 nm generated by at least one LED and a plasma discharge of a gas.

10. The color display of claim 1, and further comprising a light diffusing layer disposed between the radiation source and the photoluminescence color-elements plate.

11. A photoluminescence color display comprising:

a display panel comprising a plurality of red, green and blue pixel areas;

an excitation source operable to generate excitation radiation for operating the display;

a photoluminescence color-elements plate comprising at least one of;

red quantum dots material corresponding to red pixel areas that is operable to emit red light in response to said excitation radiation;

green quantum dots material corresponding to green pixel areas that is operable to generate green light in response to said excitation radiation; and

blue quantum dots material corresponding to blue pixel that is operable to emit blue light in response to said excitation radiation.

12. The liquid crystal display of claim 11, wherein said quantum dots materials comprise cadmium free quantum dots.

13. The liquid crystal display of claim 11, wherein said quantum dots materials comprise materials selected from the group consisting of:

cadmium selenide (CdSe);

cadmium zinc selenide (Cd_xZn_1-xSe);

cadmium zinc selenide sulfide (CdZnSeS);

cadmium selenide sulfide (CdSe_xS_1-x);

cadmium telluride (CdTe);

cadmium telluride sulfide (CdTe_xS_1-x), cadmium sulfide (CdS), cadmium zinc sulfide (Cd_xZn_1-xS);

indium phosphide (InP);

indium gallium phosphide (In_xGa_1-xP);

indium arsenide (InAs);

copper indium sulfide (CuInS₂);

copper indium selenide (CuInSe₂);

copper indium sulfide selenide (CuInS_xSe_2-x);

copper indium gallium sulfide (CuIn_xGa_1-xS₂);

copper indium gallium selenide (CuIn_xGa_1-xSe₂);

copper gallium sulfide (CuGaS₂);

copper indium aluminum selenide (CuIn_xAl_1-xSe₂);

copper gallium aluminum selenide (CuGa_xAl_1-xSe₂);

copper indium sulfide zinc sulfide (CuInS_2xZnS_1-x); and

copper indium selenide zinc selenide (CuInSe_2xZnSe_1-x).

14. The liquid crystal display of claim 11, wherein said quantum dots materials comprise core/shell nano-crystals containing different materials in an onion-like structure.

15. The liquid crystal display of claim 11, wherein said quantum dots materials are deposited as a thin layer of quantum dots directly on a substrate using a contact printing process.

16. A photoluminescence color display comprising:

a display panel comprising a plurality of red, green and blue pixel areas;

an excitation source operable to generate excitation radiation for operating the display;

a photoluminescence color-elements plate comprising at least one of;

red organic dye and red quantum dot materials corresponding to red pixel areas of the display that are operable to generate red light in response to said excitation radiation;

green organic dye and green quantum dot materials corresponding to the green pixel areas of the display that are operable to generate green light in response to said excitation radiation; and

blue organic dye and blue quantum dot materials corresponding to blue pixel areas of the display that are operable to generate blue light in response to said excitation radiation

17. The liquid crystal display of claim 16, wherein the excitation source is operable to generate blue excitation light.

18. A photoluminescence liquid crystal display comprising:

a display panel comprising light transmissive front and back plates;

at least one blue LED operable to emit blue excitation light having a wavelength in a range of 400 nm to 480 nm for operating the display;

a liquid crystal disposed between the front and back plates;

a matrix of electrodes defining red, green and blue pixel areas of the display and operable to selectively induce an electric field across the liquid crystal in the pixel areas for controlling transmission of light through the pixels areas;

a first quantum dots material corresponding to red pixel areas and operable to emit red light in response to said excitation radiation; and

a second quantum dots material corresponding to green pixel areas and operable to emit green light in response to said excitation radiation,

wherein areas on of the display corresponding to the blue pixel areas allow transmission of the blue excitation light.

19. A photoluminescence color display comprising:

a display panel comprising a plurality of red, green and blue pixel areas;

an excitation source operable to generate excitation radiation for operating the display;

a photoluminescence color-elements plate comprising at least one of;

a first photoluminescence material corresponding to red pixel areas of the display that is operable to emit red light in response to said excitation radiation;

a second photoluminescence material corresponding to green pixel areas of the display that is operable to emit green light in response to said excitation radiation; and

a third photoluminescence material corresponding to blue pixel areas of the display that is operable to emit blue light in response to said excitation radiation; and

a color filter plate located on a side the display panel that is distal to the excitation source, wherein the color filter plate comprises at least one of;

first filter areas corresponding to red pixel areas of the display that are operable to allow the passage of red light;

second filter areas corresponding to green pixel areas of the display that are operable to allow the passage of green light; and

third filter areas corresponding to blue pixel areas of the display that are operable to allow the passage of blue light.

20. The display of claim 19, and further comprising a wavelength selective filter disposed between the color-element plate and the excitation source, the wavelength selective filter having a characteristic that allows the passage of excitation radiation and substantially prevents the passage of light generated by the photoluminescence materials.