Organic light emitting diode with brightness enhancer

• US 7,250,719 B2
• Filed: 08/16/2005
• Issued: 07/31/2007
• Est. Priority Date: 12/30/2004
• Status: Active Grant

• Current Assignee: Industrial Technology Research Institute
• Original Assignee: Industrial Technology Research Institute
• Inventors: Shieh, Tien-Shou, Tseng, Mei-Rurng, Kuo, Hui-Lung, Yu, Liang-Bin, Yu, Pin-Sien
• Primary Examiner(s): Patel; Vip
• Application Number:
  US11/205,408
• Publication Number:
  US 20060145600A1
• Time in Patent Office: 714 Days
• Field of Search: 313/498, 313/504, 313/506
• US Class Current: 313/504
• CPC Class Codes: H10K 50/86 Arrangements for improving contrast, e.g. preventing reflection of ambient light
• CPC Class Codes: H10K 59/8791 Arrangements for improving contrast, e.g. preventing reflection of ambient light

Abstract

An organic light emitting diode (OLED) with a brightness enhancer. The OLED comprises a substrate having a first surface and a second surface oppositely. An anode electrode is disposed on the first surface of the substrate. An organic light emitting layer is disposed on the anode electrode. A cathode electrode is disposed on the organic light emitting layer. A brightness enhancer is disposed on the second surface of the substrate.

Claims

1. An organic light emitting diode (OLED) with a brightness enhancer, comprising:

a substrate having a first surface and a second surface opposite thereto;

an anode electrode disposed on the first surface of the substrate;

an organic light emitting layer disposed on the anode electrode;

a cathode electrode disposed on the organic light emitting layer; and

a brightness enhancer disposed on the second surface of the substrate.

2. The OLED as claimed in claim 1, further comprising a polarizing film on the brightness enhancer.

3. The OLED as claimed in claim 1, wherein the substrate is transparent glass or plastic.

4. The OLED as claimed in claim 1, wherein the brightness enhancer is a reflective polarization transformation element.

5. The OLED as claimed in claim 4, wherein the brightness enhancer comprises at least a cholesterol liquid crystal thin film layer.

6. The OLED as claimed in claim 1, wherein the brightness enhancer is multilayered.

7. The OLED as claimed in claim 1, wherein the brightness enhancer comprises a film separating different polarized lights into transmitted and reflective light.

8. The OLED as claimed in claim 1, wherein the anode electrode is indium tin oxide (ITO) or indium zinc oxide (IZO).

9. The OLED as claimed in claim 1, wherein the organic light emitting layer is OLED or polymer light emitting diode (PLED).

10. The OLED as claimed in claim 1, wherein the organic light emitting layer further comprises at least one electron injection layer, an electron transfer layer, a hole injection layer and a hole transfer layer.

11. The OLED as claimed in claim 1, wherein the cathode electrode is Al, Mg, Ag, Ca or alloys thereof.

12. An organic light emitting diode (OLED) with a brightness enhancer, comprising:

a substrate;

an anode electrode disposed on the substrate;

an organic light emitting layer disposed on the anode electrode;

a cathode electrode disposed on the organic light emitting layer; and

a brightness enhancer disposed on the cathode electrode.

13. The OLED as claimed in claim 12, further comprising a transparent encapsulant on one the OLED top or bottom surface.

14. The OLED as claimed in claim 12, further comprising a polarizing film on the outermost OLED.

15. The OLED as claimed in claim 12, wherein the substrate is transparent or opaque glass or plastic substrate.

16. The OLED as claimed in claim 12, wherein the brightness enhancer is a reflective polarization transform element.

17. The OLED as claimed in claim 16, wherein the brightness enhancer comprises at least a cholesterol liquid crystal thin film layer.

18. The OLED as claimed in claim 12, wherein the brightness enhancer is multilayered.

19. The OLED as claimed in claim 12, wherein the brightness enhancer is a film separating different polarized light into transmitted and reflective light.

20. The OLED as claimed in claim 12, wherein the anode electrode is Pt, or Au metal electrode;

or indium tin oxide (ITO) or indium zinc oxide (IZO) electrode with Au, Ag, or Al reflective layer.

21. The OLED as claimed in claim 12, wherein the organic light emitting layer is OLED or polymer light emitting diode (PLED).

22. The OLED as claimed in claim 12, wherein the organic light emitting layer further comprises at least one electron injection layer, an electron transfer layer, a hole injection layer and a hole transfer layer.

23. The OLED as claimed in claim 12, wherein the cathode electrode is Al, Mg, Mg, Ca or alloys thereof;

or indium tin oxide (ITO) or indium zinc oxide (IZO) electrode with Al, Mg, Ag, or Ca thin film.