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US5457289A Expired / Lapsed US ⏱️ 0.0 years remaining

Frontally shielded capacitive touch sensor system

Assignee: 3M Innovative Properties Co
•
Filing: 1994-03-16
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Granted: 1995-10-10
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Expires: 2014-03-16
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Abstract

Abstract A frontally shielded capacitive touch sensor system includes a capacitive touch sensor having a touch sensitive surface; a front shield mounted in front of the touch sensor and extending peripherally about the surface surrounding an exposed accessible area of the touch sensitive surface; a device for providing a first voltage on the touch sensor and detecting a change in capacitance representative of a touch to the touch sensor and for providing a second voltage on the front shield for controlling the capacitance between the touch sensor and the front shield and shielding the system from stray capacitance occurring at the front shield.

Inventors

  • 👤 Hung-Chih Huang
  • 👤 Robert A. Stein

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-10 02:36
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/01; G06F3/03; G06F3/041; G06F3/044; G06F3/0444

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 103 words
A frontally shielded capacitive touch sensor system, comprising: a capacitive touch sensor having a touch sensitive surface; a front shield mounted in front of said touch sensor and extending peripherally about said surface surrounding an exposed accessible area of said touch sensitive surface; means for providing a first voltage on said touch sensor and means for detecting a change in capacitance representative of a touch to said touch sensor and for providing a second voltage on said front shield for controlling the capacitance between said touch sensor and said front shield and shielding the system from stray capacitance occurring at said front shield.
Claim 2
Dependent Claim 103 words
A frontally shielded capacitive touch sensor system, comprising: a capacitive touch sensor having a touch sensitive surface; a front shield mounted in front of said touch sensor and extending peripherally about said surface surrounding an exposed accessible area of said touch sensitive surface; means for providing a first voltage on said touch sensor and means for detecting a change in capacitance representative of a touch to said touch sensor and for providing a second voltage on said front shield for controlling the capacitance between said touch sensor and said front shield and shielding the system from stray capacitance occurring at said front shield.
Claim 3
Dependent Claim 43 words
The frontally shielded capacitive touch sensor system of claim 1 in which said second voltage is substantially equal to said first voltage and substantially eliminates the capacitance between said front shield and said surface and said stray capacitance occurring at said front shield.
Claim 4
Dependent Claim 56 words
The frontally shielded capacitive touch sensor system of claim 1 in which said second voltage is greater than said first voltage and substantially eliminates the capacitance between said front shield and said surface, said stray capacitance occurring at said front shield, and substantially compensates for stray capacitance between said exposed accessible area and the ambient atmosphere.
Claim 5
Dependent Claim 21 words
The frontally shielded capacitive touch sensor system of claim 1 in which said second voltage is less than said first voltage.
Claim 6
Dependent Claim 18 words
The frontally shielded capacitive touch sensor system of claim 1 in which said second voltage is ground voltage.
Claim 7
Dependent Claim 41 words
The frontally shielded capacitive touch sensor system of claim 1 in which said means for providing a first voltage includes a voltage distribution network disposed about the periphery of said touch sensitive surface and said front shield covers said distribution network.
Claim 8
Dependent Claim 25 words
The frontally shielded capacitive touch sensor system of claim 1 in which said front shield includes a front conductive layer and a back non-conductive layer.
Claim 9
Dependent Claim 29 words
The frontally shielded capacitive touch sensor of claim 1 in which said means for providing said first and second voltages includes conductor means for interconnecting with said touch sensor.
Claim 10
Dependent Claim 20 words
The frontally shielded capacitive touch sensor of claim 1 in which said conductor means are integral with said front shield.
Claim 11
Dependent Claim 32 words
frontally shielded capacitive touch sensor of claim 9 in which said touch sensor includes a plurality of sensing contacts and said conductor means includes a plurality of terminals for engaging said contacts.

References Cited (Backward Citations)

US4831566A Cited
US5381160A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-10-09 1999-04-10 1999-10-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-10-09 2003-04-10 2003-10-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-10-09 2007-04-10 2007-10-10 $7700.00 Window Closed / Lapsed

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