RESISTIVE TOUCH SCREEN AND METHOD FOR MANUFACTURING SAME

• US 20100156842A1
• Filed: 08/07/2009
• Published: 06/24/2010
• Est. Priority Date: 08/19/2008
• Status: Active Grant

• Current Assignee: TPK Touch Solutions (Xiamen) Inc. (TPK Holding Co., Ltd.)
• Original Assignee: Optera, Inc. (Magna International Incorporated)
• Inventors: Cherif, Mondher
• Granted Patent: US 8,610,691 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

A touch screen and method for manufacturing a touch screen includes a transparent substrate having a first surface and a second surface opposite the first surface. The transparent substrate has a first transparent conductive layer disposed on the first surface. A cover sheet is spaced from the substrate by a plurality of spacer elements and has a second transparent conductive layer coated at a surface of the cover sheet and opposed to the first transparent conductive layer. An electromagnetic interference shield is disposed at the second surface of the transparent substrate. The electromagnetic interference shield includes a third transparent conductive layer.

Claims

1. A resistive touch screen comprising:

a transparent substrate having a first surface and a second surface opposite said first surface, said substrate having a first transparent conductive layer disposed on said first surface;

a cover sheet spaced from said substrate by a plurality of spacer elements and having a second transparent conductive layer coated at a surface of said cover sheet and opposed to said first transparent conductive layer; and

an electromagnetic interference shield disposed at and substantially covering said second surface of said transparent substrate, said electromagnetic interference shield comprising a third transparent conductive layer.

2. The resistive touch screen of claim 1, wherein said electromagnetic interference shield is disposed at said second surface of said transparent substrate before said transparent substrate is cut to its final form.

3. The resistive touch screen of claim 1, wherein said first transparent conductive layer and said electromagnetic interference shield comprise the same material.

4. The resistive touch screen of claim 3, wherein said first transparent conductive layer and said electromagnetic interference shield are deposited on the respective surface of said transparent substrate in the same coating process.

5. The resistive touch screen of claim 1, wherein said first transparent conductive layer and said electromagnetic interference shield comprise indium tin oxide.

6. The resistive touch screen of claim 1, wherein said electromagnetic interference shield comprises indium tin oxide.

7. The resistive touch screen of claim 1, wherein said electromagnetic interference shield is adapted at a peripheral edge thereof for electrical ground connection.

8. The resistive touch screen of claim 1, wherein said electromagnetic interference shield has an optical transmission of at least 70 percent of light therethrough.

9. A resistive touch screen comprising:

a transparent substrate having a first surface and a second surface opposite said first surface, said substrate having a first transparent conductive layer disposed on said first surface;

a cover sheet spaced from said substrate by a plurality of spacer elements and having a second transparent conductive layer coated at a surface of said cover sheet and opposed to said first transparent conductive layer;

an electromagnetic interference shield disposed at and substantially covering said second surface of said transparent substrate, said electromagnetic interference shield comprising a third transparent conductive layer;

wherein said electromagnetic interference shield has an optical transmission of at least 70 percent of light therethrough; and

wherein said electromagnetic interference shield is adapted at a peripheral edge thereof for electrical ground connection.

10. The resistive touch screen of claim 9, wherein said electromagnetic interference shield is disposed at said second surface of said transparent substrate before said transparent substrate is cut to its final form.

11. The resistive touch screen of claim 9, wherein said first transparent conductive layer and said electromagnetic interference shield comprise the same material.

12. The resistive touch screen of claim 11, wherein said first transparent conductive layer and said electromagnetic interference shield are deposited on the respective surface of said transparent substrate in the same coating process.

13. The resistive touch screen of claim 9, wherein said first transparent conductive layer and said electromagnetic interference shield comprise indium tin oxide.

14. The resistive touch screen of claim 9, wherein said electromagnetic interference shield comprises indium tin oxide.

15. A method of manufacturing a resistive touch screen comprising:

providing a transparent substrate having a first surface and a second surface opposite said first surface, said transparent substrate having a first transparent conductive layer disposed on said first surface;

providing a cover sheet having a second transparent conductive layer coated at a surface of said cover sheet;

spacing said cover sheet from said transparent substrate by a plurality of spacer elements and with said second transparent conductive layer opposing said first transparent conductive layer of said transparent substrate; and

providing an electromagnetic interference shield at said second surface of said transparent substrate, said electromagnetic interference shield comprising a third transparent conductive layer.

16. The method of claim 15, wherein providing an electromagnetic interference shield at said second surface of said transparent substrate comprises providing an electromagnetic interference shield at said second surface of said transparent substrate before cutting said transparent substrate to its final form.

17. The method of claim 15, wherein providing an electromagnetic interference shield at said second surface of said transparent substrate comprises providing an electromagnetic interference shield at said second surface of said transparent substrate after oxidizing said first transparent conductive layer and before reducing said first transparent conductive layer.

18. The method of claim 15, wherein said first transparent conductive layer and said electromagnetic interference shield comprise the same material.

19. The method of claim 15, wherein providing a transparent substrate comprises providing a transparent substrate and coating said first surface of said transparent substrate with a first transparent conductive layer, and wherein providing an electromagnetic interference shield at said second surface of said transparent substrate comprises coating an electromagnetic interference shield at said second surface of said transparent substrate.

20. The method of claim 19, wherein coating said first surface of said transparent substrate with a first transparent conductive layer and coating an electromagnetic interference shield at said second surface of said transparent substrate are accomplished in the same coating process.