Thermal management in electronic displays

• US 20030209977A1
• Filed: 05/12/2003
• Published: 11/13/2003
• Est. Priority Date: 05/10/2002
• Status: Active Grant

• Current Assignee: Transpacific Infinity LLC
• Original Assignee: Transpacific IP Group Limited
• Inventors: Palanisamy, Ponnusamy
• Granted Patent: US 6,914,379 B2
• Time in Patent Office: Days
• US Class Current: 313/506
• CPC Class Codes: G02F 1/13336 Combining plural substrates to produce large-area displays, e.g. tiled displays
• CPC Class Codes: G02F 1/133382 Heating or cooling of liquid crystal cells other than for activation, e.g. circuits or arrangements for temperature control, stabilisation or uniform distribution over the cell
• CPC Class Codes: G02F 1/1339 Gaskets; Spacers; Sealing of cells
• CPC Class Codes: H01J 2211/66 Cooling arrangements cooling or supporting means not being part of the tube H05K
• CPC Class Codes: H01J 2217/492 Details
• CPC Class Codes: H01J 2329/002 Cooling means
• CPC Class Codes: H01J 29/006 Arrangements for eliminating unwanted temperature effects
• CPC Class Codes: H05K 1/0203 Cooling of mounted components H05K1/0272 takes precedence
• CPC Class Codes: H05K 2201/10128 Display
• CPC Class Codes: H05K 3/0058 Laminating printed circuit boards onto other substrates, e.g. metallic substrates H05K1/0281 takes precedence
• CPC Class Codes: H05K 3/3436 having an array of bottom contacts, e.g. pad grid array or ball grid array components
• CPC Class Codes: H05K 7/20963 Heat transfer by conduction from internal heat source to heat radiating structure H05K7/20972 takes precedence
• CPC Class Codes: H10K 2102/311 Flexible OLED
• CPC Class Codes: H10K 50/8423 Metallic sealing arrangements
• CPC Class Codes: H10K 50/8426 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 50/87 Arrangements for heating or cooling
• CPC Class Codes: H10K 59/179 Interconnections, e.g. wiring lines or terminals
• CPC Class Codes: H10K 59/18 Tiled displays
• CPC Class Codes: H10K 59/8794 Arrangements for heating and cooling

Abstract

A display having improved thermal management and a method for producing the display are disclosed. The display includes a pixel structure adjacent a front panel with thermo-mechanical elements extending between a back panel and the pixel structure to dissipate heat generated by the pixel structure.

Claims

1. A method for forming a display comprising the steps of:

positioning a front panel relative to a back panel, the front and back panels defining a space therebetween;

forming at least one pixel structure adjacent the front panel in the space between the front and back panels;

forming a plurality of electrical connections extending between the back panel and the at least one pixel structure; and

forming a plurality of thermo-mechanical elements extending between the back panel and the at least one pixel structure to dissipate heat generated in the at least one pixel structure toward the back panel, wherein at least one of the plurality of thermo-mechanical elements is positioned between adjacent pixel structures of the at least one pixel structure.

2. The method of claim 1, wherein the thermo-mechanical elements are electrically non-functional.

3. The method of claim 1, further comprising the step of:

selecting an encapsulant based on heat dissipation properties; and

filling the space between the front and the back panels with the selected encapsulant to dissipate heat from the at least one pixel structure to the back panel.

4. The method of claim 1, further comprising the step of:

selecting the back panel material based on heat dissipation properties to dissipate at least the heat received from the at least one pixel structure via the thermo-mechanical elements.

5. The method of claim 1, wherein the plurality of electrical connections are formed from materials used to form the plurality of thermo-mechanical elements.

6. A display comprising:

a front panel;

a back panel spaced from the front panel, the front and back panels defining a space therebetween;

at least one pixel structure adjacent the front panel in the space between the front and back panels;

a plurality of electrical connections extending between the back panel and the at least one pixel structure; and

a plurality of thermo-mechanical elements extending between the back panel and the at least one pixel structure to dissipate heat from the at least one pixel structure toward the back panel, wherein at least one of the plurality of thermo-mechanical elements is positioned between adjacent pixel structures of the at least one pixel structure.

7. The method of claim 6, wherein the plurality of thermo-mechanical elements are electrically non-functional.

8. The display of claim 6, wherein the plurality of thermo-mechanical elements comprise a material selected from a group consisting of InSn solder and silver-filled epoxy adhesive.

9. The display of claim 6, wherein the plurality of electrical connections are formed from materials used to form the plurality of thermo-mechanical elements.

10. The display of claim 6, wherein at least one of the plurality of thermo-mechanical elements is larger than one or more of the plurality of electrical connections.

11. The display of claim 6, wherein the back panel comprises a thermally conductive material for dissipating at least the heat received at the back panel via the plurality of thermo-mechanical elements.

12. The display of claim 6, wherein the back panel is formed from a material selected from a group consisting of alumina and aluminum nitride.

13. The display of claim 6, further comprising:

an underfill encapsulant filling the space between the front and back panels to further dissipate heat from the at least one pixel structure toward the back panel.

14. The display of claim 13, wherein the underfill encapsulant is an alumina filled epoxy.

15. The display of claim 13, wherein the underfill enapsulant includes a filler selected from a group consisting of diamond, BN, AIN, BeO, and SiC.

16. The display of claim 6, wherein the at least one pixel structure comprises a display material selected-from a group consisting of organic light emitting diodes (OLED), light emitting diodes, field emissive elements, plasma elements, cathodoluminescent elements, and bistable, reflective cholesteric (BRC) liquid crystal elements.

17. An electronic display comprising:

a front panel;

a back panel spaced from the front panel, the front and back panels defining a space therebetween;

at least one pixel structure having a top surface adjacent the front panel and a bottom surface, each of the at least one pixel structure having a first electrode on the top surface and a second electrode on the bottom surface;

a first electrical connection via extending between the back panel and the first electrode of one of the at least one pixel structure;

a second electrical connection via extending between the back panel and the second electrode of the one of the at least one pixel structure; and

at least one thermo-mechanical via extending between the back panel and the one of the at least one pixel structure to dissipate heat from the one of the at least one pixel structure to the back panel, wherein at least one of the plurality of thermo-mechanical elements is positioned between adjacent pixel structures of the at least one pixel structure.

18. The display of claim 17, wherein the at least one thermo-mechanical via is electrically isolated from the first and second electrodes.

19. The display of claim 17, wherein the at least one pixel structure comprises a display material selected from a group consisting of organic light emitting diodes (OLED), light emitting diodes, field emissive elements, plasma elements, cathodoluminescent elements, and bistable, reflective cholesteric (BRC) liquid crystal elements.

20. The display of claim 17, wherein the at least one thermo-mechanical via is formed from a material selected from a group consisting of InSn solder and silver-filled epoxy adhesive.

21. The display of claim 17, wherein the back panel comprises a thermally conductive material for dissipating at least the heat received at the back panel via the at least one thermo-mechanical via.

22. The display of claim 17, wherein the back panel is formed from a material selected from a group consisting of alumina and aluminum nitride.

23. The display of claim 17, further comprising:

an underfill encapsulant filling the space between the front and back panels to further dissipate heat from the at least one pixel structure toward the back panel.

24. The display of claim 23, wherein the underfill encapsulant is an alumina filled epoxy.

25. The display of claim 23, wherein the underfill encapsulant includes a filler selected from a group consisting of diamond, BN, AIN, BeO, and SiC.