{
  "patent_number": "US 8125456",
  "country": "US",
  "title": "How Touchscreens Save Battery by Sleeping Between Touches",
  "original_title": "Multi-touch auto scanning",
  "summary": "A power-saving method for touchscreens that puts the main processor to sleep when not in use and wakes it up only when a touch is detected.",
  "what_it_does": "This patent describes a way to make touchscreens more energy-efficient by creating an autonomous 'sniff' mode. When the screen hasn't been touched for a while, the system disables the main sensor processor and its system clock to save power. During this idle time, dedicated 'auto-scan' logic periodically checks the panel for activity. If a touch is detected, the logic automatically wakes up the main processor to handle the input, ensuring the device remains responsive while minimizing battery drain.",
  "what_it_does_not_cover": [
    "Does not cover touchscreens that remain fully powered on at all times.",
    "Does not cover wake-up methods triggered by physical buttons or external sensors (like accelerometers).",
    "Does not cover software-based power management that runs entirely on the main CPU without dedicated hardware scan logic."
  ],
  "filed": "2007-01-03",
  "granted": "2012-02-28",
  "expires": "2027-01-03",
  "status": "active",
  "holder": "Apple Inc",
  "holder_url": "https://patentbrief.org/company/apple-inc",
  "inventors": [
    {
      "name": "Thomas James Wilson",
      "url": "https://patentbrief.org/inventor/thomas-james-wilson"
    },
    {
      "name": "Minh-Dieu Thi Vu",
      "url": "https://patentbrief.org/inventor/minh-dieu-thi-vu"
    },
    {
      "name": "Christoph Horst Krah",
      "url": "https://patentbrief.org/inventor/christoph-horst-krah"
    }
  ],
  "times_cited": 21,
  "tags": [
    "consumer_electronics",
    "semiconductors",
    "telecommunications"
  ],
  "abstract": "A system and method for autonomously scanning a sensor panel device, such as a multi-touch panel, is disclosed. In one embodiment, the system and method disables a sensor panel processor after a first predetermined amount of time has elapsed without the sensor panel device sensing any events. One or more system clocks can also be disabled to conserve power. While the processor and one or more system clocks are disabled, the sensor panel device can periodically autonomously scan the sensor panel for touch activity. Accordingly, if one or more results from the autonomous scans exceed a threshold, the sensor panel device re-enables the processor and one or more clocks to actively scan the sensor panel. If the threshold is not exceeded, then the sensor panel device continues to periodically autonomously scan the sensor panel without intervention from the processor. Furthermore, the sensor panel device can periodically perform calibration functions to account for any drift that may be present in the system.",
  "url": "https://patentbrief.org/patent/us/8125456/multi-touch-capacitive-scanning",
  "markdown_url": "https://patentbrief.org/patent/us/8125456/multi-touch-capacitive-scanning/md",
  "google_patents_url": "https://patents.google.com/patent/US8125456",
  "relatedPatents": [
    {
      "patentNumber": "8493330",
      "countryCode": "US",
      "title": "How Touchscreens Precisely Align Signals to Detect Your Touch",
      "url": "https://patentbrief.org/patent/us/8493330/individual-channel-phase-delay-scheme"
    },
    {
      "patentNumber": "8619056",
      "countryCode": "US",
      "title": "How Touchscreens Tell Real Touches From False Ghost Touches",
      "url": "https://patentbrief.org/patent/us/8619056/ghost-resolution-for-a-capacitive-touch-panel"
    },
    {
      "patentNumber": "7663607",
      "countryCode": "US",
      "title": "How Multi-Touch Screens Track Multiple Fingers at Once",
      "url": "https://patentbrief.org/patent/us/7663607/multipoint-touchscreen"
    },
    {
      "patentNumber": "7479949",
      "countryCode": "US",
      "title": "How Touchscreens Understand Your Finger Swipes and Scrolls",
      "url": "https://patentbrief.org/patent/us/7479949/iphone-multi-touch"
    },
    {
      "patentNumber": "5825352",
      "countryCode": "US",
      "title": "Logitech's Method for Using Two Fingers on a Touchpad",
      "url": "https://patentbrief.org/patent/us/5825352/apple-pinch-to-zoom"
    }
  ]
}