Assembly of microencapsulated electronic displays

• US 6,312,304 B1
• Filed: 12/14/1999
• Issued: 11/06/2001
• Est. Priority Date: 12/15/1998
• Status: Expired due to Term

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: E Ink Holdings Incorporated
• Inventors: Drzaic, Paul S., Duthaler, Gregg M., Kazlas, Peter T.
• Primary Examiner(s): Ramsey, Kenneth J.
• Application Number:
  US09/461,463
• Time in Patent Office: 693 Days
• Field of Search: 445/24, 445/25, 313/504, 313/506
• US Class Current: 445/24
• CPC Class Codes: B41J 3/4076 printing on rewritable, bistable "electronic paper" by a focused electric or magnetic field
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/1345 Conductors connecting electrodes to cell terminals
• CPC Class Codes: G02F 1/1362 Active matrix addressed cells G02F1/134336, G02F1/134363 take precedence
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 1/16757 Microcapsules
• CPC Class Codes: G02F 2201/42 Arrangements for providing conduction through an insulating substrate

Abstract

An electro-optical device is manufactured by separately manufacturing an electronic component and an optical component and subsequently integrating the electronic and the optical components. Separate fabrication of the two components allows each component to be manufactured using processes which optimize its properties.

Claims

1. A method of manufacturing an electro-optical device comprising:

a) providing a modulating layer comprising a first substrate and an electro-optical material provided adjacent the first substrate, the modulating layer being capable of changing a visual state upon application of an electric field;

b) providing a pixel layer comprising a second substrate, a plurality of pixel electrodes provided on a front surface of the second substrate and a plurality of contact pads provided on a rear surface of the second substrate, each pixel electrode connected to a contact pad through a via extending through the second substrate;

c) providing a circuit layer comprising a third substrate and at least one circuit element; and

d) laminating the modulating layer, the pixel layer and the circuit layer to form the electro-optical device.

2. The method of claim 1 wherein step d) comprises d1) laminating the pixel layer and the modulating layer to form a subassembly and d2) laminating the circuit layer and the subassembly, thereby forming the electro-optical device.

3. The method of claim 1 wherein the electro-optical material comprises a plurality of capsules, each capsule comprising a plurality of particles dispersed in a fluid.

4. The method of claim 3 wherein the plurality of particles comprises electrophoretic particles.

5. The method of claim 1 wherein the electro-optical material comprises liquid crystals.

6. The method of claim 1 wherein the electro-optical material comprises a plurality of capsules, each capsule comprising a bichromal sphere dispersed in a fluid.

7. The method of claim 1 wherein the modulating layer comprises a flexible first substrate.

8. The method of claim 1 wherein the modulating layer comprises an organic first substrate.

9. The method of claim 1 wherein the modulating layer comprises a first substrate and a transparent common electrode provided on the first substrate.

10. The method of claim 1 wherein the pixel layer comprises a second insulative substrate.

11. The method of claim 1 further comprising forming the pixel layer by printing a conductive material on the front surface of the second substrate to form the pixel electrodes.

12. The method of claim 1 further comprising forming the pixel layer by evaporating a conductive material on the front surface of the second substrate to form the pixel electrodes.

13. The method of claim 1 wherein step d) comprises d1) integrating the pixel layer and the modulating layer to form a subassembly and d2) integrating the circuit layer and the subassembly, thereby forming the electro-optical device.

14. The method of claim 2 wherein step d1) comprises encapsulating the pixel layer and the modulating layer.

15. The method of claim 2 wherein step d1) comprises sealing together an edge of the pixel layer and an edge of the modulating layer.

16. The method of claim 13 wherein step d1) comprises laminating the pixel layer and the modulating layer by providing the front surface of the pixel layer adjacent the electro-optical material of the modulating layer.

17. The method of claim 2 wherein step d2) comprises bonding the circuit substrate layer and the subassembly.

18. The method of claim 2 wherein step d1) comprises inserting an adhesive layer between the pixel layer and modulating layer.

19. The method of claim 2 wherein step d2) comprises bonding the circuit layer to the rear surface of the pixel layer.

20. The method of claim 19 wherein step d2) comprises bonding the circuit layer and the subassembly through one of thermocompression, thermosonic bonding and mechanical bonding.

21. The method of claim 19 wherein step d2) comprises bonding the circuit layer and the subassembly by inserting an adhesive between the circuit layer and the subassembly.

22. The method of claim 21 wherein step d2) comprises inserting an adhesive layer comprising an anisotropically conductive material between the circuit layer and the subassembly.

23. The method of claim 2 further comprising printing an adhesive layer adjacent the rear surface of the pixel layer around the contact pads prior to performing step d2).

24. The method of claim 13 wherein step a) comprises providing a first modulating layer and a second modulating layer, step b) comprises providing a first pixel layer and a second pixel layer, step d1) comprises laminating the first pixel layer and the first modulating layer to form a first assembly and laminating the second pixel layer and the second modulating layer to form a second assembly, and step d2) comprises placing the circuit layer between the first assembly and the second assembly.

25. The method of claim 13 wherein the circuit layer comprises a plurality of contacts provided on a front surface of the third substrate and step d2) comprises laminating the modulating layer and the subassembly such that a contact of the circuit layer is provided adjacent the contact pad of the pixel layer.

26. An electro-optical device manufactured by the method of claim 13.

27. The method of claim 1 wherein step d) comprises d1) laminating the pixel layer and the circuit layer to form a subassembly and d2) laminating the modulating layer and the subassembly to form the electro-optical device.

28. An electro-optical device manufactured by the method of claim 27.

29. The method of claim 1 wherein the circuit layer comprises at least one of a data line driver, a select line driver, a power supply, a sensor, a logic element, a memory device, and a communication device.

30. The method of claim 1 further comprising testing the modulating layer and the circuit layer prior to performing step d).

31. The method of claim 1 wherein the circuit layer comprises a plurality of non-linear devices.

32. The method of claim 1 wherein the circuit layer comprises a plurality of organic-based field effect transistors.

33. The method of claim 1 further comprising printing an organic-based field effect transistor array on a front surface of the third substrate of the circuit layer.

34. A method of manufacturing an electro-optical device comprising:

providing a modulating layer comprising a first substrate and an electro-optical material provided adjacent the first substrate, the modulating layer being capable of changing a visual state upon application of an electric field;

providing a pixel layer comprising a second substrate, a plurality of pixel electrodes provided on a front surface of the second substrate and a plurality of contact pads provided on a rear surface of the second substrate, each pixel electrode connected to a contact pad through a via extending through the second substrate;

providing a plurality of via holes through the second substrate and filling the via holes with a conductive material;

providing a circuit layer comprising a third substrate and at least one circuit element; and

integrating the modulating layer, the pixel layer and the circuit layer to form the electro-optical device.