TOUCH DETECTION TECHNIQUES FOR CAPACITIVE TOUCH SENSE SYSTEMS

• US 20170024078A1
• Filed: 10/03/2016
• Published: 01/26/2017
• Est. Priority Date: 03/31/2006
• Status: Abandoned Application

• Current Assignee: Monterey Research, LLC (Vector Capital Corporation)
• Original Assignee: Monterey Research, LLC (Vector Capital Corporation)
• Inventors: Bokma, Louis W., Page, Andrew C., Seguine, Dennis R.
• Application Number:
  US15/283,954
• Publication Number:
  US 20170024078A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01R 27/2605 Measuring capacitance capacitive sensors G01D5/24
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/04182 Filtering of noise external to the device and not generated by digitiser components
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: H03K 17/955 using a capacitive detector
• CPC Class Codes: H03K 17/9622 using a plurality of detectors, e.g. keyboard
• CPC Class Codes: H03K 2217/94026 Automatic threshold calibration; e.g. threshold automatically adapts to ambient conditions or follows variation of input
• CPC Class Codes: H03K 2217/96066 Thumbwheel, potentiometer, scrollbar or slider simulation by touch switch
• CPC Class Codes: H03K 2217/960705 Safety of capacitive touch and proximity switches, e.g. increasing reliability, fail-safe

Abstract

A technique for recognizing and rejecting false activation events related to a capacitance sense interface includes measuring a capacitance value of a capacitance sensor within the capacitance sense interface to generate a measured capacitance value. The measured capacitance value is analyzed to determine a baseline capacitance value for the capacitance sensor. The baseline capacitance value may be updated based at least in part upon a weighted moving average of the measured capacitance value. The measured capacitance value may also be analyzed to determine whether the capacitance sensor was activated during a startup phase and to adjust the baseline capacitance value in response to determining that the capacitance sensor was activated during the startup phase.

Claims

1. A machine-readable storage medium that provides instructions that, if executed by a machine, will cause the machine to perform operations comprising:

measuring a capacitance value of a capacitance sensor within a capacitance sense interface to generate a measured capacitance value;

analyzing the measured capacitance value to determine a baseline capacitance value for the capacitance sensor; and

updating the baseline capacitance value in real-time.