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).

  • Publication number: 20220382409
    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: Application
    Filed: August 8, 2022
    Publication date: December 1, 2022
    Inventors: Shahrooz SHAHPARNIA, Christoph H. KRAH
  • Publication number: 20220276739
    Abstract: An electronic device may have a touch sensitive display that is insensitive to the presence of moisture. An array of pixels in the display may be used to display images. A display cover layer may overlap the array of pixels. A light source may illuminate an external object such as a finger of a user when the object contacts a surface of the display cover layer. This creates scattered light that may be detected by an array of light sensors. The light source may supply light to an edge of the display cover layer at an angle that ensures total internal reflection within the display cover layer is sustained across the display cover layer even when the display cover layer is immersed in water or otherwise exposed to moisture.
    Type: Application
    Filed: May 6, 2022
    Publication date: September 1, 2022
    Inventors: Mohammad Yeke Yazdandoost, Christoph H. Krah
  • Publication number: 20220276738
    Abstract: An electronic device may have a touch sensitive display that is insensitive to the presence of moisture. An array of pixels in the display may be used to display images. A display cover layer may overlap the array of pixels. A light source may illuminate an external object such as a finger of a user when the object contacts a surface of the display cover layer. This creates scattered light that may be detected by an array of light sensors. The light source may supply light to an edge of the display cover layer at an angle that ensures total internal reflection within the display cover layer is sustained across the display cover layer even when the display cover layer is immersed in water or otherwise exposed to moisture.
    Type: Application
    Filed: May 6, 2022
    Publication date: September 1, 2022
    Inventors: Mohammad Yeke Yazdandoost, Christoph H. Krah
  • Patent number: 11409353
    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: August 24, 2018
    Date of Patent: August 9, 2022
    Assignee: Apple Inc.
    Inventors: Shahrooz Shahparnia, Christoph H. Krah
  • Patent number: 11353985
    Abstract: A switching circuit is disclosed. The switching circuit can comprise a plurality of pixel mux blocks, each of the pixel mux blocks configured to be coupled to a respective touch node electrode on a touch sensor panel, and each of the pixel mux blocks including logic circuitry. The switching circuit can also comprise a plurality of signal lines configured to be coupled to sense circuitry, at least one of the signal lines configured to transmit a touch signal from one of the respective touch node electrodes to the sense circuitry. The logic circuitry in each pixel mux block of the plurality of pixel mux blocks can be configured to control the respective pixel mux block so as to selectively couple the respective pixel mux block to any one of the plurality of signal lines.
    Type: Grant
    Filed: August 26, 2020
    Date of Patent: June 7, 2022
    Assignee: Apple Inc.
    Inventor: Christoph H. Krah
  • Patent number: 11353994
    Abstract: An electronic device may have a touch sensitive display that is insensitive to the presence of moisture. An array of pixels in the display may be used to display images. A display cover layer may overlap the array of pixels. A light source may illuminate an external object such as a finger of a user when the object contacts a surface of the display cover layer. This creates scattered light that may be detected by an array of light sensors. The light source may supply light to an edge of the display cover layer at an angle that ensures total internal reflection within the display cover layer is sustained across the display cover layer even when the display cover layer is immersed in water or otherwise exposed to moisture.
    Type: Grant
    Filed: March 1, 2021
    Date of Patent: June 7, 2022
    Assignee: Apple Inc.
    Inventors: Mohammad Yeke Yazdandoost, Christoph H. Krah
  • Publication number: 20220057897
    Abstract: In some examples, a touch screen can include touch electrodes that can function as drive (Tx) electrodes and sense (Rx) electrodes during a touch sensing operation of the electronic device. The drive electrodes can include +Tx electrodes and ?Tx electrodes that can receive drive signals that can have the same amplitude and frequency and opposite phases, for example. In some examples, the surface areas of the +Tx electrodes and the ?Tx electrodes can be the same and the distances of the +Tx electrodes and ?Tx electrodes from the Rx electrodes can be different. In some examples, the total charge coupled to a proximate or touching object can be zero, which can mitigate problems associated with ungrounded or poorly grounded objects in contact with the touch screen.
    Type: Application
    Filed: August 20, 2020
    Publication date: February 24, 2022
    Inventors: William Matthew Pender PAUL, Christoph H. KRAH, Bin HUANG, Stanley Bo-Ting WANG
  • Publication number: 20220004284
    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: September 21, 2021
    Publication date: January 6, 2022
    Inventors: Minh-Dieu Thi VU, Thomas James WILSON, Christoph H. KRAH
  • Patent number: 11199933
    Abstract: Some touch screens can be formed by at least partially integrating touch sensing circuitry into a display pixel stackup. In some examples, noise can be introduced into touch sensor panel measurements, for example, from display data lines of a display device proximate to the touch sensor panel. In some examples, rows or columns of touch electrodes can be split and a first portion of the touch sensor panel can be stimulated to measure capacitance and noise and a second portion of the touch sensor panel can be unstimulated and measure noise. In some examples, both the first and the second portions of the touch sensor panel can be stimulated using orthogonal stimulation codes. In some examples, measurements from the first and/or second portions of the touch sensor panel can be subtracted from measurements from the other portion of the touch sensor panel to eliminate or reduce common mode noise.
    Type: Grant
    Filed: October 26, 2020
    Date of Patent: December 14, 2021
    Assignee: Apple Inc.
    Inventors: Christoph H. Krah, Du Chen
  • Patent number: 11194423
    Abstract: A system and method for autonomously scanning a sensor panel device is disclosed. A sensor panel processor can be disabled 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. 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, the sensor panel device continues to periodically autonomously scan the sensor panel without intervention from the processor. The sensor panel device can periodically perform calibration functions to account for any drift that may be present in the system.
    Type: Grant
    Filed: June 24, 2020
    Date of Patent: December 7, 2021
    Assignee: Apple Inc.
    Inventors: Christoph H. Krah, Minh-Dieu Thi Vu, Thomas James Wilson
  • Publication number: 20210357063
    Abstract: An integrated touchscreen can include light emitting diodes or organic light emitting diodes (LEDs/OLEDs), display chiplets and touch chiplets disposed in a visible area of the integrated touch screen. For example, the LEDs/OLEDs, display chiplets and touch chiplets can be placed on a substrate by a micro-transfer tool. The integrated touchscreen can also include electrodes disposed in the visible area of the integrated touch screen. The electrodes can be capable of providing display functionality via the one or more display chiplets during display operation (e.g., operating as cathode terminals of the LEDs during the display operation) and capable of providing touch functionality via the touch chiplets during touch operation (e.g., touch node electrodes can be formed from groups of the electrodes and sensed). In some examples, the touch node electrodes can be formed and coupled to touch chiplets via the display chiplets.
    Type: Application
    Filed: July 23, 2021
    Publication date: November 18, 2021
    Inventors: Christian M. SAUER, Christoph H. KRAH, Derek K. SHAEFFER, Hasan AKYOL, Henry C. JEN, Hopil BAE, John T. WETHERELL, Thierry S. DIVEL, Xiang LU
  • Patent number: 11132097
    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: May 25, 2020
    Date of Patent: September 28, 2021
    Assignee: Apple Inc.
    Inventors: Minh-Dieu Thi Vu, Thomas James Wilson, Christoph H. Krah
  • Patent number: 11086463
    Abstract: A multi-modal touch controller configured to operate in different modes. In some examples, the multi-modal touch controller can be operated in a first mode corresponding to a guarded self-capacitance scan. In some examples, the multi-modal touch controller can be operated in a second mode corresponding to offset-compensated mutual capacitance scan. In some examples, the multi-modal controller can be operated in a third mode corresponding to a mutual and self-capacitance scan. The multi-modal touch controller can advantageously allow one touch sensing chipset to be used across different types of guarded touch sensor panels and across different modes of operation.
    Type: Grant
    Filed: September 18, 2018
    Date of Patent: August 10, 2021
    Assignee: Apple Inc.
    Inventor: Christoph H. Krah
  • Publication number: 20210240304
    Abstract: A multipoint touch surface controller is disclosed herein. The controller includes an integrated circuit including output circuitry for driving a capacitive multi-touch sensor and input circuitry for reading the sensor. Also disclosed herein are various noise rejection and dynamic range enhancement techniques that permit the controller to be used with various sensors in various conditions without reconfiguring hardware.
    Type: Application
    Filed: February 8, 2021
    Publication date: August 5, 2021
    Inventors: Steven P. HOTELLING, Christoph H. KRAH, Brian Q. HUPPI
  • Patent number: 11079878
    Abstract: Techniques for mitigating noise in a touch signal are disclosed. To reduce or eliminate noise in a touch signal, the touch activity can be filtered out of a touch signal, thus isolating the noise. In some examples, the noise is then provided to the non-inverting input port of a differential amplifier while the unfiltered touch signal is provided to the inverting input port of the differential amplifier. The noise, which is now common on both inputs, is automatically eliminated or reduced by the differential amplifier.
    Type: Grant
    Filed: July 10, 2020
    Date of Patent: August 3, 2021
    Assignee: Apple Inc.
    Inventor: Christoph H. Krah
  • Patent number: 11073927
    Abstract: An integrated touchscreen can include light emitting diodes or organic light emitting diodes (LEDs/OLEDs), display chiplets and touch chiplets disposed in a visible area of the integrated touch screen. For example, the LEDs/OLEDs, display chiplets and touch chiplets can be placed on a substrate by a micro-transfer tool. The integrated touchscreen can also include electrodes disposed in the visible area of the integrated touch screen. The electrodes can be capable of providing display functionality via the one or more display chiplets during display operation (e.g., operating as cathode terminals of the LEDs during the display operation) and capable of providing touch functionality via the touch chiplets during touch operation (e.g., touch node electrodes can be formed from groups of the electrodes and sensed). In some examples, the touch node electrodes can be formed and coupled to touch chiplets via the display chiplets.
    Type: Grant
    Filed: July 19, 2019
    Date of Patent: July 27, 2021
    Assignee: Apple Inc.
    Inventors: Christian M. Sauer, Christoph H. Krah, Derek K. Shaeffer, Hasan Akyol, Henry C. Jen, Hopil Bae, John T. Wetherell, Thierry S. Divel, Xiang Lu
  • Patent number: 11016616
    Abstract: An electronic device can include an integrated touch and display chip that can operate in multiple power domains. For example, the integrated touch and display chip can operate in a guarded power domain during the touch operation and can operate in a system power domain during non-guarded display operations. In some examples, two power domains can include a guarded power domain and a system power domain, whose grounds can be differentiated by a guard buffer signal. In some examples, the guard buffer can be disposed between the integrated touch and display chip and a battery of the device. In some examples, the guard buffer can be disposed between the battery of the device and the chassis of the device.
    Type: Grant
    Filed: August 2, 2019
    Date of Patent: May 25, 2021
    Assignee: Apple Inc.
    Inventors: Christian M. Sauer, Christoph H. Krah, Steven P. Hotelling, Martin Paul Grunthaner
  • Patent number: 10990221
    Abstract: The disclosure relates to a touch and/or proximity detection system having some components operating in the guard domain and other components operating in the earth or chassis ground domain. A guard chip in the earth or chassis ground domain can include a voltage driver configured to produce a guard signal, for example. In some examples, the guard signal can be coupled to one or more shielding electrodes of a touch screen and to the ground pin of one or more touch sensing chips of the touch and/or proximity detection system. In this way, for example, the touch sensing chips, which can include sense amplifiers coupled to one or more sensing electrodes of the touch screen, can operate in the guard domain. In some examples, the guard chip can further include differential amplifiers and/or ADCs, allowing these components to operate in the earth or chassis ground domain.
    Type: Grant
    Filed: September 18, 2018
    Date of Patent: April 27, 2021
    Assignee: Apple Inc.
    Inventor: Christoph H. Krah
  • Publication number: 20210098537
    Abstract: A display may have an array of light-emitting pixels that display an image in an active area of the display. These light-emitting pixels may be visible light pixels such as red, green, and blue thin-film organic light-emitting diode pixels. The display may also have a border region that runs along a peripheral edge of the active area. The border region may be free of pixels that display image light, whereas the active area may be free of light detectors. A non-optical touch sensor such as a capacitive touch sensor may overlap the active area to gather touch input from the active area. The non-optical touch sensor may not overlap any portion of the border region. In the border region, an optical sensor formed from infrared light-emitting pixels and infrared light-sensing pixels or other optical sensing circuitry may serve as an optical touch sensor.
    Type: Application
    Filed: July 27, 2020
    Publication date: April 1, 2021
    Inventors: Christoph H. Krah, Mohammad Yeke Yazdandoost
  • Publication number: 20210064165
    Abstract: Some touch screens can be formed by at least partially integrating touch sensing circuitry into a display pixel stackup. In some examples, noise can be introduced into touch sensor panel measurements, for example, from display data lines of a display device proximate to the touch sensor panel. In some examples, rows or columns of touch electrodes can be split and a first portion of the touch sensor panel can be stimulated to measure capacitance and noise and a second portion of the touch sensor panel can be unstimulated and measure noise. In some examples, both the first and the second portions of the touch sensor panel can be stimulated using orthogonal stimulation codes. In some examples, measurements from the first and/or second portions of the touch sensor panel can be subtracted from measurements from the other portion of the touch sensor panel to eliminate or reduce common mode noise.
    Type: Application
    Filed: October 26, 2020
    Publication date: March 4, 2021
    Inventors: Christoph H. KRAH, Du CHEN