Color display apparatus having electroluminescence elements

• US 6,392,340 B2
• Filed: 02/26/1999
• Issued: 05/21/2002
• Est. Priority Date: 02/27/1998
• Status: Expired due to Term

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Shibata, Kenichi, Yoneda, Kiyoshi
• Primary Examiner(s): Font, Frank G.
• Assistant Examiner(s): LAUCHMAN, LAYLA G
• Application Number:
  US09/259,130
• Publication Number:
  US 20010026127A1
• Time in Patent Office: 1,180 Days
• Field of Search: 313/506, 313/498, 313/499, 313/500, 313/501, 313/503, 313/112
• US Class Current: 313/506
• CPC Class Codes: H01J 1/74 with adjacent dots or lines of different luminescent material
• CPC Class Codes: H10K 2102/3026 Top emission
• CPC Class Codes: H10K 2102/321 Inverted OLED, i.e. having cathode between substrate and anode
• CPC Class Codes: H10K 50/805 Electrodes
• CPC Class Codes: H10K 50/813 characterised by their shape
• CPC Class Codes: H10K 50/865 comprising light absorbing layers, e.g. light-blocking layers
• CPC Class Codes: H10K 59/123 Connection of the pixel electrodes to the thin film transistors [TFT]
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]
• CPC Class Codes: H10K 59/805 Electrodes
• CPC Class Codes: H10K 59/80515 characterised by their shape
• CPC Class Codes: H10K 59/8792 comprising light absorbing layers, e.g. black layers

Abstract

A color display apparatus comprises a substrate; thin film transistors formed on the substrate, each of the thin film transistors having a source electrode and a drain electrode; electroluminescence elements respectively formed over the thin film transistors and driven by the thin film transistors, each of the electroluminescence elements having a cathode connected to a source electrode or drain electrode of a thin film transistor, a luminous element layer, and an anode electrode sequentially disposed thereover. A color filter or fluorescent color conversion layer acting as a color element is formed on the side of the anode electrode of an electroluminescence element. The same luminous layer material is used for each display pixel to display a color image.

Claims

1. A color display apparatus comprising:

a substrate;

thin film transistors formed on said substrate, each of said thin film transistors having a source electrode and a drain electrode;

electroluminescence elements respectively formed over said thin film transistors, each of said electroluminescence elements having a cathode connected to said source electrode or said drain electrode, a luminous layer, and an anode sequentially formed thereover; and

color elements respectively disposed directly on said anodes of said electroluminescence elements.

2. The color display apparatus defined in claim 1, wherein each of said color elements comprises a color filter layer formed on a transparent substrate.

3. The color display apparatus defined in claim 1, wherein each of said color elements comprises a color filter layer through which a light of a predetermined wavelength among an emitted light from said luminous layer can pass.

4. The color display apparatus defined in claim 3, wherein each of said color elements comprises a color filter layer formed on a transparent substrate, said color filter passing the light of a predetermined wavelength among the emitted light from said luminous layer.

5. The color display apparatus defined in claim 3, wherein said luminous layer of each of said electroluminescence elements is formed of a white luminous material;

and wherein said color filter layer includes a layer for red light through which red light within white light emitted from said luminous layer passes, a layer for green light through which green light within the white light passes and a layer for blue light through which blue light within the white light passes.

6. The color display apparatus defined in claim 1, wherein each of said color elements comprises a color conversion layer of fluorescent materials -formed on a transparent substrate.

7. The color display apparatus defined in claim 1, wherein each of said color elements comprises a color conversion layer of fluorescent materials for converting a light from said luminous layer into a light of a predetermined wavelength.

8. The color display apparatus defined in claim 7, wherein each of said color elements comprises said color conversion layer of fluorescent materials formed on a transparent substrate, for converting said light from said luminous layer into said light of a predetermined wavelength.

9. The color display apparatus defined in claim 8, wherein said color conversion layer of fluorescent materials comprises a layer for red light which converts said light emitted from said luminous layer into red light, a layer for green light which converts said light into green light, and a layer for blue light which converts said light into blue light.

11. The color display apparatus defined in claim 1, wherein each of said electroluminescence elements further comprises an organic electroluminenscence element using an organic material for said luminous layer.

10. A color display apparatus, comprising:

a substrate;

thin film transistors formed on said substrate, each of said thin film transistors having a source electrode and a drain electrode;

electroluminescence elements respectively formed over said thin film transistors, each of said electroluminescence elements having a cathode connected to said source electrode or said drain electrode, a luminous layer, and an anode sequentially formed thereover; and

color elements respectively arranged on the sides of said anodes of said electroluminescence elements,

wherein each of said anodes of said electroluminescence elements is shaped in a comb, mesh, or grid planar pattern.

24. The color display apparatus defined in claim 10, wherein each of said color elements comprises a color filter layer formed on a transparent substrate.

25. The color display apparatus defined in claim 10, wherein each of said color elements comprises a color filter layer through which a light of a predetermined wavelength among an emitted light from said luminous layer can pass.

26. The color display apparatus defined in claim 25, wherein each of said color elements comprises a color filter layer formed on a transparent substrate, said color filter passing said light of a predetermined wavelength among said emitted light from said luminous layer.

27. The color display apparatus defined in claim 25, wherein said luminous layer of each of said electroluminescence elements is formed of a white luminous material;

and wherein said color filter layer includes a layer for red light through which red light within white light emitted from said luminous layer passes, a layer for green light through which green light within the white light passes and a layer for blue light through which blue light within the white light passes.

28. The color display apparatus defined in claim 10, wherein each of said color elements comprises a color conversion layer of fluorescent materials formed on a transparent substrate.

29. The color display apparatus defined in claim 10, wherein each of said color elements comprises a color conversion layer of fluorescent materials for converting a light from said luminous layer into a light of a predetermined wavelength.

30. The color display apparatus defined in claim 29, wherein each of said color elements comprises a color conversion layer of fluorescent materials formed on a transparent substrate, for converting said light from said luminous layer into said light of a predetermined wavelength.

31. The color display apparatus defined in claim 30, wherein said color conversion layer of fluorescent materials comprises a layer for red light which converts said light emitted from said luminous layer into red light, a layer for green light which converts said light into green light, and a layer for blue light which converts said light into blue light.

12. A color display apparatus comprising:

a substrate;

thin film transistors formed on said substrate, each of said thin film transistors having a source and a drain; and

electroluminescence elements respectively formed over said thin film transistors, each of said electroluminescence elements having a cathode connected to said source or said drain, a luminous layer, and an anode sequentially formed in that order,

wherein said luminous layer is formed of a same material for each of said electroluminescence elements, and

color filters are respectively provided over said anodes of said electroluminescence elements.

13. The color display apparatus defined in claim 12,

wherein said color filters are respectively formed over said anodes such that each of said color filters is assigned to each of said electroluminescence elements for permitting transmission of a light having a predetermined wavelength.

14. The color display apparatus defined in claim 12,

wherein said luminous layer is composed of a white color emissive material, and each of said color filters is a color of red, green, or blue and each of said color filters is assigned to each of said electroluminescence elements.

15. A color display apparatus having a plurality of display pixels on a substrate, said display pixels comprising:

thin film transistors formed on said substrate, each of said thin film transistors having a source and a drain;

electroluminescence elements respectively formed over said thin film transistors, each of said electroluminescence elements having a cathode connected to said source or said drain, a luminous layer, and an anode sequentially formed in that order;

insulating layers for separating at least said luminous layer of each of said display pixels; and

color elements provided respectively over said anodes of said electroluminescence elements.

16. The color display apparatus defined in claim 15, wherein each of said color elements comprises a color filter layer formed on a transparent substrate.

17. The color display apparatus defined in claim 15, wherein each of said color elements comprises a color filter layer through which a light of a predetermined wavelength among an emitted light from said luminous layer can pass.

18. The color display apparatus defined in claim 17, wherein each of said color elements comprises a color filter layer formed on a transparent substrate, said color filter passing said light of a predetermined wavelength among said emitted light from said luminous layer.

19. The color display apparatus defined in claim 17, wherein said luminous layer of each of said electroluminescence elements is formed of a white luminous material;

and wherein said color filter layer includes a layer for red light through which red light within white light emitted from said luminous layer passes, a layer for green light through which green light within the white light passes and a layer for blue light through which blue light within the white light passes.

20. The color display apparatus defined in claim 15, wherein each of said color elements comprises a color conversion layer of fluorescent materials formed on a transparent substrate.

21. The color display apparatus defined in claim 15, wherein each of said color elements comprises a color conversion layer of fluorescent materials for converting a light from said luminous layer into a light of a predetermined wavelength.

22. The color display apparatus defined in claim 21, wherein each of said color elements comprises a color conversion layer of fluorescent materials formed on a transparent substrate, for converting said light from said luminous layer into said light of a predetermined wavelength.

23. The color display apparatus defined in claim 22, wherein said color conversion layer of fluorescent materials comprises a layer for red light which converts said light emitted from said luminous layer into red light, a layer for green light which converts said light into green light, and a layer for blue light which converts said light into blue light.