Patents by Inventor Christoph H. Krah

Christoph H. Krah has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Common electrode auto-compensation method
    Patent number: 10146359
    Abstract: A system is disclosed. The system can comprise dynamic drive circuitry configured to drive a plurality of electrodes on a touch screen. The system can also comprise a switching circuit configured to selectively couple the dynamic drive circuitry to one or more of the plurality of electrodes. The system can also comprise a display circuitry configured to selectively update a plurality of display pixels on the touch screen. The dynamic drive circuitry can be configured to set its output based on which of the plurality of electrodes are selectively coupled to the first drive circuitry and which of the display pixels are updated by the display circuitry.
    Type: Grant
    Filed: April 1, 2016
    Date of Patent: December 4, 2018
    Assignee: Apple Inc.
    Inventors: Howard Tang, Christoph H. Krah, Paolo Sacchetto, Chaohao Wang
  • Automatic low noise frequency selection
    Patent number: 10139890
    Abstract: Automatic low noise frequency selection for a touch sensitive device is disclosed. A low noise stimulation frequency can be automatically selected by device logic without intervention of the device processor to stimulate the device to sense a touch event at the device. The device logic can automatically select a set of low noise frequencies from among various frequencies based on the amount of noise introduced by the device at the various frequencies, where the frequencies with the lower noise amounts can be selected. The device logic can also automatically select a low noise frequency from among the selected set as the low noise stimulation frequency. The device logic can be implemented partially or entirely in hardware.
    Type: Grant
    Filed: May 18, 2015
    Date of Patent: November 27, 2018
    Assignee: Apple Inc.
    Inventors: Thomas James Wilson, Christoph H. Krah
  • CHANNEL SCAN LOGIC
    Publication number: 20180321791
    Abstract: A device that can autonomously scan a sensor panel is disclosed. Autonomous scanning can be performed by implementing channel scan logic. In one embodiment, channel scan logic carries out many of the functions that a processor would normally undertake, including generating timing sequences and obtaining result data; comparing scan result data against a threshold value (e.g., in an auto-scan mode); generating row count; selecting one or more scanning frequency bands; power management control; and performing an auto-scan routine in a low power mode.
    Type: Application
    Filed: July 18, 2018
    Publication date: November 8, 2018
    Inventors: Minh-Dieu Thi VU, Thomas James WILSON, Christoph H. KRAH
  • Touch sensor panel with multi-power domain chip configuration
    Patent number: 10120520
    Abstract: A touch sensing system is disclosed. The touch sensing system includes a guard signal generation chip operating in a first power domain referenced to a first voltage, the guard signal generation chip configured to generate a guard signal. A touch sensing chip operates in a second power domain, different from the first power domain, referenced to the guard signal, the touch sensing chip configured to sense touch at one or more touch electrodes included in a touch sensor panel operating in the second power domain referenced to the guard signal, and the touch sensing chip a different chip than the guard signal generation chip. A voltage regulator is configured to selectively regulate a voltage of the guard signal at the touch sensing chip.
    Type: Grant
    Filed: July 28, 2017
    Date of Patent: November 6, 2018
    Assignee: Apple Inc.
    Inventors: Christoph H. Krah, Christian M. Sauer
  • Self capacitance touch sensing
    Patent number: 10061444
    Abstract: Self capacitance touch circuits to cancel the effects of parasitic capacitance in a touch sensitive device are disclosed. One circuit can generate a parasitic capacitance cancelation signal that can be injected into touch sensing circuitry to cancel the parasitic capacitance. Another circuit can adjust the phase and magnitude of the parasitic capacitance cancelation signal based on characteristics of channels in the touch sensing circuitry so as to fine tune the parasitic capacitance cancelations. Another circuit can drive a guard plate and touch panel electrodes so as to cancel the parasitic capacitances between the panel and the plate and between the electrodes.
    Type: Grant
    Filed: October 30, 2013
    Date of Patent: August 28, 2018
    Assignee: Apple Inc.
    Inventors: Shahrooz Shahparnia, Christoph H. Krah
  • Coarse scan and targeted active mode scan for touch and stylus
    Patent number: 10061449
    Abstract: Power consumption of touch sensing operations for touch sensitive devices can be reduced by implementing a coarse scan (e.g., banked common mode scan) to coarsely detect the presence or absence of an object touching or proximate to a touch sensor panel and the results of the coarse scan can be used to dynamically adjust the operation of the touch sensitive device to perform or not perform a fine scan (e.g., targeted active mode scan). In some examples, the results of the coarse scan can be used to program a touch controller for the next touch sensing frame to idle when no touch event is detected or to perform a fine scan when one or more touch events are detected. In some examples, the results of the coarse scan can be used to abort a scheduled fine scan during the current touch sensing frame when no touch event is detected.
    Type: Grant
    Filed: September 29, 2015
    Date of Patent: August 28, 2018
    Assignee: Apple Inc.
    Inventors: Vivek Pant, Shahrooz Shahparnia, Marduke Yousefpor, Christoph H. Krah
  • Channel scan architecture for multiple stimulus multi-touch sensor panels
    Patent number: 10042476
    Abstract: A channel scan architecture for detecting touch events on a touch sensor panel is disclosed. The channel scan architecture can combine drive logic, sense channels and channel scan logic on a single monolithic chip. The channel scan logic can be configured to implement a sequence of scanning processes in a panel subsystem without intervention from a panel processor. The channel scan architecture can provide scan sequence control to enable the panel processor to control the sequence in which individual scans are implemented in the panel subsystem. Type of scans that can be implemented in the panel subsystem can include a spectral analysis scan, touch scan, phantom touch scan, ambient light level scan, proximity scan and temperature scan.
    Type: Grant
    Filed: May 18, 2016
    Date of Patent: August 7, 2018
    Assignee: Apple Inc.
    Inventors: Thomas James Wilson, Christoph H. Krah, Minh-Dieu Thi Vu
  • Dynamic voltage generation for touch-enabled displays
    Patent number: 10042459
    Abstract: The disclosed embodiments relate to a system that provides power for a touch-enabled display, wherein the touch-enabled display cycles between a display mode and a touch mode. During the display mode, the system drives a display-mode voltage to the touch-enabled display through a power output, wherein the power output is coupled through a display-mode capacitor CD to ground. Next, during a transition from the display mode to the touch mode, the system couples the power output through a touch-mode capacitor CT to ground, wherein CT was previously charged to a touch-mode voltage, which causes the power output to rapidly transition to the touch-mode voltage. Then, during the touch mode, the system drives the touch-mode voltage through the power output.
    Type: Grant
    Filed: September 8, 2015
    Date of Patent: August 7, 2018
    Assignee: Apple Inc.
    Inventors: Christoph H. Krah, Yafei Bi, Kevin J. White
  • Channel scan logic
    Patent number: 10031609
    Abstract: A device that can autonomously scan a sensor panel is disclosed. Autonomous scanning can be performed by implementing channel scan logic. In one embodiment, channel scan logic carries out many of the functions that a processor would normally undertake, including generating timing sequences and obtaining result data; comparing scan result data against a threshold value (e.g., in an auto-scan mode); generating row count; selecting one or more scanning frequency bands; power management control; and performing an auto-scan routine in a low power mode.
    Type: Grant
    Filed: June 3, 2015
    Date of Patent: July 24, 2018
    Assignee: Apple Inc.
    Inventors: Minh-Dieu Thi Vu, Thomas James Wilson, Christoph H. Krah
  • Three-dimensional imaging and display system
    Patent number: 9958960
    Abstract: A three-dimensional imaging and display system is provided in which input is optically detected in an imaging volume by measuring the path length of an amplitude modulated scanning beam as a function of the phase shift thereof. Visual image feedback concerning the detected input is presented.
    Type: Grant
    Filed: October 23, 2014
    Date of Patent: May 1, 2018
    Assignee: Apple Inc.
    Inventor: Christoph H. Krah
  • PROXIMITY AND MULTI-TOUCH SENSOR DETECTION AND DEMODULATION
    Publication number: 20180095560
    Abstract: The use of one or more proximity sensors in combination with one or more touch sensors in a multi-touch panel to detect the presence of a finger, body part or other object and control or trigger one or more functions in accordance with an “image” of touch provided by the sensor outputs is disclosed. In some embodiments, one or more infrared (IR) proximity sensors can be driven with a specific stimulation frequency and emit IR light from one or more areas, which can in some embodiments correspond to one or more multi-touch sensor “pixel” locations. The reflected IR signal, if any, can be demodulated using synchronous demodulation. In some embodiments, both physical interfaces (touch and proximity sensors) can be connected to analog channels in the same electrical core.
    Type: Application
    Filed: November 22, 2017
    Publication date: April 5, 2018
    Inventors: Steven P. HOTELLING, Christoph H. KRAH
  • Methods and apparatuses using control indicators for data processing systems
    Patent number: 9935631
    Abstract: A control indication assembly. A first control mounted on a surface of a computer is coupled to a first sensor, to a first sensing circuit to send an electrical signal to the first control when a user-touch occurs to the first sensor, and to a first indicator to indicate an occurrence of said user-touch. A second control mounted on a surface of a display which is coupled to the computer is coupled to a second sensor, to a second sensing circuit to send an electrical signal to said second control when said user-touch occurs to the display, and to a second indicator to indicate an occurrence of the user-touch. The first and second control are configured such that the first and second indicator are synchronized to exhibit identical behaviors when the user-touch occurs to either the first control or the second control.
    Type: Grant
    Filed: April 27, 2011
    Date of Patent: April 3, 2018
    Assignee: Apple Inc.
    Inventors: Andrew Gong, Brian Q. Huppi, Christoph H. Krah, Richard D. Cappels, Duncan R. Kerr, Michael Culbert
  • ANALOG FRONT END WITH VARIABLE GAIN CONTROL FOR TOUCH APPLICATIONS
    Publication number: 20180059870
    Abstract: An analog front end (AFE) can be implemented with automatic variable gain control for self-capacitance based touch- and proximity-sensitive touch sensor panels or touch screens. The AFE can include a charge amplifier and an oversampled analog-to-digital converter (ADC). The AFE can also include multiple signal paths between the charge amplifier and the ADC. The variable gain control can monitor the output of the oversampled ADC and, based on the oversampled ADC output, automatically select one of the multiple signal paths. When the output of the ADC indicates a proximity condition (e.g., relatively small signal, relatively large noise headroom when compared with a touch condition), the automatically selected signal path can amplify the charge amplifier output. The bit resolution of the oversampled ADC in the AFE can be relaxed as a result of the variable gain control.
    Type: Application
    Filed: August 10, 2017
    Publication date: March 1, 2018
    Inventor: Christoph H. KRAH
  • TOUCH SENSOR PANEL WITH MULTI-POWER DOMAIN CHIP CONFIGURATION
    Publication number: 20180032176
    Abstract: A touch sensing system is disclosed. The touch sensing system includes a guard signal generation chip operating in a first power domain referenced to a first voltage, the guard signal generation chip configured to generate a guard signal. A touch sensing chip operates in a second power domain, different from the first power domain, referenced to the guard signal, the touch sensing chip configured to sense touch at one or more touch electrodes included in a touch sensor panel operating in the second power domain referenced to the guard signal, and the touch sensing chip a different chip than the guard signal generation chip. A voltage regulator is configured to selectively regulate a voltage of the guard signal at the touch sensing chip.
    Type: Application
    Filed: July 28, 2017
    Publication date: February 1, 2018
    Inventors: Christoph H. KRAH, Christian M. SAUER
  • Proximity and multi-touch sensor detection and demodulation
    Patent number: 9830036
    Abstract: The use of one or more proximity sensors in combination with one or more touch sensors in a multi-touch panel to detect the presence of a finger, body part or other object and control or trigger one or more functions in accordance with an “image” of touch provided by the sensor outputs is disclosed. In some embodiments, one or more infrared (IR) proximity sensors can be driven with a specific stimulation frequency and emit IR light from one or more areas, which can in some embodiments correspond to one or more multi-touch sensor “pixel” locations. The reflected IR signal, if any, can be demodulated using synchronous demodulation. In some embodiments, both physical interfaces (touch and proximity sensors) can be connected to analog channels in the same electrical core.
    Type: Grant
    Filed: June 10, 2016
    Date of Patent: November 28, 2017
    Assignee: Apple Inc.
    Inventors: Steven P. Hotelling, Christoph H. Krah
  • CONCURRENT TOUCH AND NEGATIVE PIXEL SCAN
    Publication number: 20170329441
    Abstract: A concurrent touch and negative pixel scan performed at a touch panel is disclosed. The concurrent scan can include sensing an object proximate to the touch panel and sensing a negative pixel effect, based the object's grounding condition, at the touch panel, at the same time. As a result, sense signals indicative of the proximity of the object and coupling signals indicative of the negative pixel effect's magnitude can be captured concurrently. Because the negative pixel effect can cause errors or distortions in the sense signals, the coupling signals can be used to compensate the sense signals for the negative pixel effect.
    Type: Application
    Filed: August 1, 2017
    Publication date: November 16, 2017
    Inventors: Christoph H. KRAH, Marduke YOUSEFPOR
  • Electronic Device with an Integrated Touch Sensing and Force Sensing Device
    Publication number: 20170285810
    Abstract: An integrated touch sensing and force sensing device is included in an electronic device. The integrated touch sensing and force sensing device includes a force-sensitive layer operably attached to an input surface, a first electrode layer attached to a first surface of the force-sensitive layer, and a second electrode layer attached to a second surface of the force-sensitive layer. An analog front end processing channel is operable to process a touch signal that is based on a change in an electrical property between the first and second electrode layers and operable to process a force signal that is based on an electrical property generated by the force-sensitive layer based on a force applied to the input surface.
    Type: Application
    Filed: June 19, 2017
    Publication date: October 5, 2017
    Inventor: Christoph H. Krah
  • Three-dimensional imaging and display system
    Patent number: 9766716
    Abstract: A three-dimensional imaging and display system is provided in which user input is optically detected in an imaging volume by measuring the path length of an amplitude modulated scanning beam as a function of the phase shift thereof. Visual image user feedback concerning the detected user input is presented.
    Type: Grant
    Filed: July 11, 2014
    Date of Patent: September 19, 2017
    Assignee: Apple Inc.
    Inventor: Christoph H. Krah
  • Electronic device with an integrated touch sensing and force sensing device
    Patent number: 9690408
    Abstract: An integrated touch sensing and force sensing device is included in an electronic device. The integrated touch sensing and force sensing device includes a force-sensitive layer operably attached to an input surface, a first electrode layer attached to a first surface of the force-sensitive layer, and a second electrode layer attached to a second surface of the force-sensitive layer. An analog front end processing channel is operable to process a touch signal that is based on a change in an electrical property between the first and second electrode layers and operable to process a force signal that is based on an electrical property generated by the force-sensitive layer based on a force applied to the input surface.
    Type: Grant
    Filed: September 26, 2014
    Date of Patent: June 27, 2017
    Assignee: Apple Inc.
    Inventor: Christoph H. Krah
  • TOUCH SCREEN LIQUID CRYSTAL DISPLAY
    Publication number: 20170147119
    Abstract: Disclosed herein are liquid-crystal display (LCD) touch screens that integrate the touch sensing elements with the display circuitry. The integration may take a variety of forms. Touch sensing elements can be completely implemented within the LCD stackup but outside the not between the color filter plate and the array plate. Alternatively, some touch sensing elements can be between the color filter and array plates with other touch sensing elements not between the plates. In another alternative, all touch sensing elements can be between the color filter and array plates. The latter alternative can include both conventional and in-plane-switching (IPS) LCDs. In some forms, one or more display structures can also have a touch sensing function. Techniques for manufacturing and operating such displays, as well as various devices embodying such displays are also disclosed.
    Type: Application
    Filed: February 3, 2017
    Publication date: May 25, 2017
    Inventors: Steve Porter HOTELLING, Wei CHEN, Christoph H. KRAH, John Greer ELIAS, Wei Hsin YAO, John Z. ZHONG, Andrew Bert HODGE, Brian R. LAND, Willem den BOER