User interface

• US 20030197688A1
• Filed: 04/22/2002
• Published: 10/23/2003
• Est. Priority Date: 04/22/2002
• Status: Abandoned Application

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Frank, Paul D., Aufderheide, Brian E.
• Application Number:
  US10/127,099
• Publication Number:
  US 20030197688A1
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 2203/04113 Peripheral electrode pattern in resistive digitisers, i.e. electrodes at the periphery of the resistive sheet are shaped in patterns enhancing linearity of induced field
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

A resistive touch panel including a base layer is disclosed. The touch panel includes a resistive layer covering the active area of the touch panel. The touch panel also includes a plurality of electrodes disposed to induce a voltage gradient across the resistive layer. The touch panel also includes a linearization pattern comprising a plurality of resistors disposed over at least a portion of the resistive layer for maintaining the uniformity of the voltage gradient across the resistive layer. The touch panel also includes an insulator covering a least a portion of the linearization pattern. The insulator reduces changes in the voltage gradient over time. A method of making a resistive touch screen is also disclosed.

Claims

1. A resistive touch panel having an active area and including a base layer comprising:

a resistive layer covering the active area of the touch panel;

a plurality of electrodes disposed to induce a voltage gradient across the resistive layer;

a linearization pattern comprising a plurality of resistors disposed over at least a portion of the resistive layer for maintaining the uniformity of the voltage gradient across the resistive layer; and

an insulator covering a least a portion of the linearization pattern;

wherein the insulator reduces changes in the voltage gradient over time.

2. The resistive touch panel of claim 1 wherein the resistance of the plurality of resistors increases less than about 30% at 60°

C. and 95% RH after two weeks.

3. The resistive touch panel of claim 2 wherein the resistance of the plurality of resistors increases less than about 15% at 60°

C. and 95% RH after two weeks.

4. The resistive touch panel of claim 3 wherein the resistance of the plurality of resistors increases less than about 5% at 60°

C. and 95% RH after two weeks.

6. The resistive touch panel of claim 1 wherein the resistance of the plurality of resistors does not substantially increase after curing the insulator.

7. The resistive touch panel of claim 6 wherein the resistance of the plurality of resistors increases by less than 5% about one day after curing the insulator.

5. The resistive touch panel of claim 5 wherein the insulator does not substantially increase the resistance of the plurality of resistors at ambient temperature and ambient humidity.

8. The resistive touch panel of claim 5 wherein the insulator increases the resistance of the voltage gradient by less than about 5% at ambient temperature and ambient humidity after two weeks.

9. The resistive touch panel of claim 8 wherein the insulator increases the resistance of the plurality of resistors by less than about 5% at ambient temperature and ambient humidity after thirty days.

10. The resistive touch panel of claim 9 wherein the insulator inhibits upward drift of the resistance of the plurality of resistors.

11. The resistive touch panel of claim 10 wherein the insulator comprises an ink.

12. The resistive touch panel of claim 11 wherein the insulator is transparent.

13. The resistive touch panel of claim 12 wherein the insulator comprises an acrylate monomer configured to polymerize when exposed to UV radiation.

14. The resistive touch panel of claim 10 wherein the resistors are disposed over the periphery of the resistive layer.

15. The resistive touch panel of claim 14 further comprising a flexible layer coupled to the base layer by a fastener.

16. The resistive touch panel of claim 15 wherein the resistive layer comprises indium tin oxide.

17. The resistive touch panel of claim 16 wherein the linearization pattern comprises a plurality of discontinuous segments of conductive ink positioned proximate the perimeter of the base layer and separated by the plurality of resistors.

18. The resistive touch panel of claim 17 wherein the conductive ink of the linearization pattern has a greater conductivity than the conductivity of the plurality of resistors.

19. The resistive touch panel of claim 18 wherein the plurality of resistors comprises a conductive coating that is continuous over the base layer and further comprises at least one of tin oxide and indium tin oxide.

20. An electronic display including a touch panel comprising:

a linearization pattern comprising a plurality of resistors disposed to straighten a voltage gradient induced by electrodes coupled to a resistive layer;

an insulator covering at least a portion of the linearization pattern;

wherein the insulator reduces changes in the voltage gradient over time.

21. The electronic display of claim 20 wherein the resistance of the plurality of resistors increases by less than about 30% at 60°

C. and 95% RH after two weeks.

22. The electronic display of claim 21 wherein the resistance of the plurality of resistors increases the resistance of the plurality of resistors by less than about 15% at 60°

C. and 95% RH after two weeks.

23. The electronic display of claim 20 wherein the insulator is a UV curable.

24. The electronic display of claim 20 wherein the insulator does not substantially increase the resistance of the plurality of resistors at ambient temperature and humidity after curing the insulator.

25. The electronic display of claim 23 wherein the insulator comprises an acrylate based material.

26. The electronic display of claim 25 wherein the insulator includes a photoinitiator.

27. The electronic display of claim 26 wherein the insulator includes silicone and talc.

28. The electronic display of claim 26 wherein the insulator is screen printable.

29. The electronic display of claim 28 wherein the insulator is substantially free of solvent.

30. The electronic display of claim 28 wherein the insulator is substantially free of epoxy.

31. A method of making a resistive touch screen having a base layer, a plurality of electrodes of the base layer separated by a resistor, and an insulator coupled to the resistor, the method comprising:

applying the insulator to the resistor;

wherein the insulator does not substantially increase the resistance of the resistor at ambient temperature and humidity.

32. The method of claim 31 wherein the resistance of the plurality of resistors increases by less than about 30% at 60°

C. and 95% RH after two weeks.

33. The method of claim 32 wherein applying the insulator comprises screen printing the insulator.

34. The method of claim 33 further comprising curing the insulator with UV radiation.

35. A resistive touch screen comprising:

a base layer coupled to a flexible layer by a fastener;

a linearization region comprising a plurality of resistors between a first conductor and a second conductor for reducing a bow of a voltage gradient between the first conductor and the second conductor;

an insulator means for maintaining the resistance of the plurality of resistors.

36. The touch screen of claim 35 wherein the resistance of the plurality of resistor is increased by the insulator means by less than about 30% at 60°

C. and 95% RH after two weeks.

37. The touch screen of claim 36 wherein the insulator means comprises an acrylate based material that is UV curable.