Method of encapsulating a display element with frit wall and laser beam

• US 7,537,504 B2
• Filed: 11/15/2006
• Issued: 05/26/2009
• Est. Priority Date: 12/06/2005
• Status: Expired due to Fees

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Logunov, Stephan Lvovich, Becken, Keith James
• Primary Examiner(s): Patel; Nimeshkumar D.
• Assistant Examiner(s): Hines; Anne M
• Application Number:
  US11/599,738
• Publication Number:
  US 20070128967A1
• Time in Patent Office: 923 Days
• Field of Search: 445 24- 25
• US Class Current: 445/25
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 59/8722 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 71/00 Manufacture or treatment specially adapted for the organic devices covered by this subclass

Abstract

A method of minimizing stress in an OLED device laser sealing process using an elongated laser beam. A laser beam having an intensity distribution which decreases as a function of distance from the longitudinal axis of the beam is passed through a mask to create an elongated beam having a length-wise intensity distribution which decreases as a function of distance from the axis of the beam and a substantially constant width-wise intensity distribution. The elongated beam is traversed over a line of frit disposed between two substrates. The tails of the length-wise intensity distribution provide for a slow cool down of the frit as the beam traverses the line of frit.

Claims

1. A method of encapsulating a display element comprising:

providing a first substrate and a second substrate separated by at least one frit wall, and at least one display element disposed between the first and second substrates;

impinging a laser beam on the at least one frit wall through the first substrate;

traversing the beam along a length of the wall to heat the frit wall and seal the first substrate to the second substrate; and

wherein an intensity distribution of the impinging beam in a direction of travel of the beam is decreasing as a function of distance from a longitudinal axis of the beam, and an intensity distribution of the impinging beam in a direction orthogonal to the direction of travel varies by no more than about 10% from a peak intensity of the beam.

2. The method according to claim 1 wherein the frit wall comprises a closed frame.

3. The method according to claim 1 wherein the beam has a spot diameter greater than a width w_f of the frit wall.

4. The method according to claim 1 wherein the beam passes through a mask comprising a transparent slit prior to impinging on the frit.

5. The method according to claim 4 wherein the mask is disposed over the first substrate.

6. The method according to claim 4 wherein the mask comprises a reflective surface.

7. The method according to claim 1 wherein the beam is traversed at a speed greater than about 10 mm/s.

8. The method according to claim 1 wherein the beam is traversed at a speed greater than about 30 mm/s.

9. The method according to claim 1 wherein the traversing comprises reflecting the beam from at least one moving reflector.

10. The method according to claim 1 wherein the reflector is moved by a galvonometer.

11. The method according to claim 1 wherein the frit wall has a height between 10 and 30 μ

m.

12. The method according to claim 1 wherein the mask comprises an absorbing surface.

13. The method according to claim 3 wherein the spot diameter is greater than about 2 times the width w_f of the frit wall.