Patents Represented by Law Firm D'Alessandro, Frazzinni & Ritchie
  • Patent number: 5374787
    Abstract: A proximity sensor system includes a sensor matrix array having a characteristic capacitance on horizontal and vertical conductors connected to sensor pads. The capacitance changes as a function of the proximity of an object or objects to the sensor matrix. The change in capacitance of each node in both the X and Y directions of the matrix due to the approach of an object is converted to a set of voltages in the X and Y directions. These voltages are processed by analog circuitry to develop electrical signals representative of the centroid of the profile of the object, i.e., its position in the X and Y dimensions. The profile of position may also be integrated to provide Z-axis (pressure) information.
    Type: Grant
    Filed: August 31, 1993
    Date of Patent: December 20, 1994
    Assignee: Synaptics, Inc.
    Inventors: Robert J. Miller, Stephen Bisset, Timothy P. Allen, Gunter Steinbach