Laser patterning of encapsulated organic light emitting diodes

• US 8,173,453 B2
• Filed: 01/07/2008
• Issued: 05/08/2012
• Est. Priority Date: 12/19/2002
• Status: Expired due to Fees

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: McCormick, Fred B., Fitzer, Robert C., Tran, Hung T.
• Primary Examiner(s): Nguyen, Kimberly
• Assistant Examiner(s): NGUYEN, DUY T V
• Application Number:
  US11/970,268
• Publication Number:
  US 20080160789A1
• Time in Patent Office: 1,583 Days
• Field of Search: 438/25, 438/26, 438/99, 438/795, 257/E21.001
• US Class Current: 438/26
• CPC Class Codes: H10K 2101/80 Composition varying spatially, e.g. having a spatial gradient
• CPC Class Codes: H10K 50/125 specially adapted for multicolour light emission, e.g. for emitting white light
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 50/85 Arrangements for extracting light from the devices
• CPC Class Codes: H10K 59/17 Passive-matrix OLED displays
• CPC Class Codes: H10K 59/179 Interconnections, e.g. wiring lines or terminals
• CPC Class Codes: H10K 59/221 Static displays, e.g. displaying permanent logos
• CPC Class Codes: H10K 59/8722 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 59/875 Arrangements for extracting light from the devices
• CPC Class Codes: H10K 71/211 by selective transformation of an existing layer

Abstract

Patterning an organic light emitting diode (OLED) after it has been encapsulated by permanently changing the light emissivity of the diodes. The OLED includes an intervening layer between a source of laser treatment and a light emitting layer. Depending on the composition of the light emitting layer, the laser treatment will enhance or diminish brightness.

Claims

1. A method for laser patterning encapsulated organic light emitting diodes comprising:

providing an encapsulated organic light emitting diode having a light emitting layer and an intervening layer, and

treating one or more areas of the light emitting layer with a laser beam, which laser beam energy is transmitted through an electrode layer,

wherein the intervening layer comprises a layer between a source of the laser beam and the light emitting layer, and wherein the intervening layer is within the encapsulated organic light emitting diode,

wherein the energy level of the laser beam is below the ablation threshold of the light emitting layer and the intervening layer,

wherein the laser beam is transmitted through the intervening layer to treat the one or more areas, and

wherein the light emission of the one or more areas of the light emitting layer treated with the laser beam are permanently changed.

2. The method of claim 1 wherein the electrode is an anode.

3. The method of claim 2 wherein the anode is transparent.

4. The method of claim 1 wherein the light emitting layer comprises a light emitting polymer.

5. The method of claim 4 wherein the light output of the treated areas of the polymeric layer have an increased light emission.

6. The method of claim 1 wherein the light emitting layer comprises a small molecule material.

7. The method of claim 6 wherein the light output of the treated area of the small molecule layer has a decreased light emission.

8. The method of claim 1 wherein the light emitting layer comprises a molecularly-doped polymer.

9. The method of claim 8 wherein the light output of the treated area of the molecularly-doped polymer layer has a decreased light emission.

10. The method of claim 1 wherein the encapsulated organic light emitting diode has discrete pixels and wherein individual pixels are treated.

11. The method of claim 10 wherein individual pixels are treated to adjust the uniformity of emissivity across the display.

12. The method of claim 11 wherein the emission color of individual pixels is changed by the treatment.

13. The method of claim 12 wherein the treated pixels contain dyes that change color upon irradiation.

14. The method of claim 1 wherein the encapsulated organic light emitting diode is treated to adjust brightness.

15. The method of claim 1 wherein the light emitting layer comprises sublayers and two or more sublayers are treated such that the sublayers have the same or different patterned images.

16. The method of claim 1 wherein the electrode is a cathode.

17. The method of claim 1 wherein the intervening layer comprises a substrate.

18. The method of claim 17 wherein the treatment of the one or more areas does not cause ablation of the substrate.

19. The method of claim 1 wherein the intervening layer comprises an absorptive material.