Close illumination system

Patent metadata

Field	Value
Publication number	US-10243162-B2
Application number	US-201615160309-A
Country	US
Kind code	B2
Filing date	May 20, 2016
Priority date	Jun 17, 2015
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

Devices suitable for close illumination of an object are provided. Such a device includes a highly transparent electrode and a highly reflective, weakly transmissive electrode, with other OLED layers disposed between them. During operation in close proximity to an object, the object is illuminated by the device, while still allowing a user to see through the device.

First claim

We claim:

1. An organic light-emitting device comprising:
a flexible substrate;
a highly-transparent electrode layer disposed over the substrate, the highly-transparent electrode layer having a peak transmittance of at least 90% in the 400-700 nm range;
an emissive layer comprising an organic emissive material disposed over the highly-transparent electrode; and
a highly-reflective, weakly-transmissive electrode layer disposed over the emissive layer, the highly-reflective, weakly-transmissive electrode having a minimum transmittance of not more than 20% and a peak reflectance of at least 5% in the 400-700 nm range.

2. The device of claim 1 , wherein, during operation of the device, a first luminance measured from the side of the device closest to the substrate is at least 8 times a second luminance measured from the side of the device farthest from the substrate.

3. The device of claim 1 , wherein the highly-reflective electrode layer comprises a continuous layer.

4. The device of claim 1 , wherein the highly-reflective electrode layer comprises a grid of reflective electrode material.

5. The device of claim 4 , wherein the grid of reflective electrode material occupies a total area of not more than 25% the total area of the emissive layer.

6. The device of claim 4 , wherein the transmittance of the highly-reflective electrode layer is not more than about 2% within the 400-700 nm wavelength range.

7. The device of claim 4 , wherein the organic emissive layer is patterned according to the grid of the highly-reflective electrode layer.

8. The device of claim 4 , wherein the grid comprises a grid arrangement selected from the group consisting of: square, rectangular, triangular, hexagonal, circle, oval, and a combination thereof.

9. The device of claim 4 , wherein the grid comprises grid lines of less than 500 μm in width.

10. The device of claim 4 , wherein the width of the grid lines is selected from a group consisting of: less than 200 μm, less than 150 μm, less than 100 μm, and less than 50 μm.

11. The device of claim 1 , wherein the organic light emitting device is a single-pixel device.

12. The device of claim 1 , wherein at least one of an electrode of the highly-transparent electrode layer has a non-uniform transmittance within the 400-700 nm range and an electrode of the highly-reflective, weakly-transmissive electrode layer has a reflectance within the 400-700 nm range.

13. A device comprising:
the organic light emitting device of claim 1 ;
a battery configured to provide a voltage across the organic emissive layer;
a switch configured to control a circuit through which the battery provides the voltage;
a driver configured to drive the organic light emitting device; and
a mechanical package housing the battery, the switch, and the driver;
wherein the largest dimension of the mechanical package is not more than ½ the largest dimension of an active area of the emissive layer, and the mechanical package is not disposed in a stack with the emissive layer.

14. The device of claim 13 wherein the device is a bookmark.

15. The device of claim 14 , wherein no dimension of the mechanical packaging is greater than about 50 mm.

16. The device of claim 13 , wherein the device is not thicker than 2 mm.

17. The device of claim 13 , further comprising a magnification layer.

18. The device of claim 13 , wherein the battery is a rechargeable battery.

19. The device of claim 18 , further comprising an external charging port in electrical communication with the rechargeable battery.

20. A method of fabricating an organic light-emitting device, the method comprising:
obtaining a flexible substrate;
fabricating a highly-transparent electrode layer disposed over the substrate, the highly-transparent electrode layer having a peak transmittance of at least 90% in the 400-700 nm range;
fabricating an emissive layer comprising an organic emissive material disposed over the highly-transparent electrode; and
fabricating a highly-reflective, weakly-transmissive electrode layer disposed over the emissive layer, the highly-reflective, weakly-transmissive electrode having a minimum transmittance of not more than 20% and a peak reflectance of at least 50% in the 400-700 nm range.

Assignees

• Universal Display Corp

Inventors

• Ma Ruiqing
• Paynter Jason
• Silvernail Jeffrey
• Brown Julia J
• Premutico Mauro

Classifications

• G02B25/02

  with means for illuminating object viewed · CPC title

• H01L51/5206

  Electricity · mapped topic

• H01L2251/5338

  Electricity · mapped topic

• H01L51/5221

  Electricity · mapped topic

• F21W2131/3005

  for books, i.e. reading lights attachable to books · CPC title