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).

  • Patent number: 10541280
    Abstract: A touch screen configured for optical touch sensing and user identification using organic light emitting diodes (OLEDs) is disclosed. In some examples, one or more OLEDs can be used to display one or more images on the device, can be configured to emit light for optical touch sensing, and/or can be configured to detect a reflection of the emitted light. The touch screen can include a spatial filter configured to focus light emitted from the OLEDs and/or reflected light detected by the OLEDs for improved optical touch sensing. Using optical touch sensors, the touch screen can be capable of discerning between water and an object (e.g., finger) and/or noise (e.g., ambient light) and an object. The touch screen can also be capable of identifying (e.g., authenticating) a user using the active area of the device.
    Type: Grant
    Filed: September 15, 2017
    Date of Patent: January 21, 2020
    Assignee: Apple Inc.
    Inventors: Christoph H. Krah, Kingsuk Brahma
  • Publication number: 20200019265
    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: September 24, 2019
    Publication date: January 16, 2020
    Inventors: Christoph H. KRAH, Christian M. SAUER
  • Patent number: 10488992
    Abstract: A multi-chip touch architecture for scalability can include one or more touch controller application specific integrated circuits (ASICs), and one or more switching circuits coupled between the one or more touch controller ASICs and the touch sensor panel. The number of touch controller ASICs and switching circuits can be scaled based on the size of the touch sensor panel. The touch controller ASICs can include an interface for data transfer between the touch controller ASICs to allow for parallel processing of an image of touch by more than one touch controller ASIC. The touch controller ASIC can also include a memory directly accessible by more than one processing circuit (e.g., hardware accelerators), and circuitry to dynamically adjust the coupling between portions (e.g., banks) of memory and inputs of the one or more processing circuits to minimize data transfer and improve processing speeds.
    Type: Grant
    Filed: January 11, 2016
    Date of Patent: November 26, 2019
    Assignee: Apple Inc.
    Inventors: Shahrooz Shahparnia, Vivek Pant, Christoph H. Krah
  • Patent number: 10459587
    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: November 2, 2018
    Date of Patent: October 29, 2019
    Assignee: Apple Inc.
    Inventors: Christoph H. Krah, Christian M. Sauer
  • Publication number: 20190286220
    Abstract: Power management for a touch controller is disclosed. The touch controller can include a transmit section for transmitting stimulation signals to an associated touch sensor panel to drive the panel, where the touch controller can selectively adjust the transmit section to reduce power during the transmission. The touch controller can also include a receive section for receiving touch signals resulting from the driving of the panel, where the touch controller can selectively adjust the receive section to reduce power during the receipt of the touch signals. The touch controller can also include a demodulation section for demodulating the received touch signals to obtain touch event results, where the touch controller can selectively adjust the demodulation section to reduce power during the demodulation of the touch signals. The touch controller can also selectively reduce power below present low levels during idle periods.
    Type: Application
    Filed: February 14, 2019
    Publication date: September 19, 2019
    Inventors: Christoph H. KRAH, Thomas James WILSON
  • Patent number: 10402025
    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: Grant
    Filed: August 1, 2017
    Date of Patent: September 3, 2019
    Assignee: Apple Inc.
    Inventors: Christoph H. Krah, Marduke Yousefpor
  • Patent number: 10282026
    Abstract: Measuring an effect of body capacitance in a touch sensitive device is disclosed. This effect can be caused by poor grounding of a user or other objects touching the device or of the device itself. The device can operate in a stray capacitance mode to measure a body capacitance effect and in a normal mode to detect a touch on the device. During the stray capacitance mode, the device can obtain a body capacitance measurement from the device. During the normal mode, the device can obtain a touch measurement from the device. The device can calculate a body capacitance factor based on a ratio between the body capacitance measurement and the touch measurement and use the body capacitance factor to compensate for erroneous or distorted touch output values from the device. Various components of the device can be switchably configured according to the particular mode.
    Type: Grant
    Filed: September 9, 2016
    Date of Patent: May 7, 2019
    Assignee: Apple Inc.
    Inventors: Christoph H. Krah, Steven P. Hotelling, Marduke Yousefpor
  • Publication number: 20190102004
    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: Application
    Filed: September 18, 2018
    Publication date: April 4, 2019
    Inventor: Christoph H. KRAH
  • Publication number: 20190102037
    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: Application
    Filed: September 18, 2018
    Publication date: April 4, 2019
    Inventor: Christoph H. KRAH
  • Publication number: 20190095006
    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: Application
    Filed: August 27, 2018
    Publication date: March 28, 2019
    Inventors: Shahrooz SHAHPARNIA, Christopher Tenzin MULLENS, Martin Paul GRUNTHANER, Adam GEBOFF, Vivek PANT, Marduke YOUSEFPOR, Christoph H. KRAH, Shwetabh VERMA, Sumant RANGANATHAN
  • Publication number: 20190073061
    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: November 2, 2018
    Publication date: March 7, 2019
    Inventors: Christoph H. KRAH, Christian M. SAUER
  • Patent number: 10222854
    Abstract: Power management for a touch controller is disclosed. The touch controller can include a transmit section for transmitting stimulation signals to an associated touch sensor panel to drive the panel, where the touch controller can selectively adjust the transmit section to reduce power during the transmission. The touch controller can also include a receive section for receiving touch signals resulting from the driving of the panel, where the touch controller can selectively adjust the receive section to reduce power during the receipt of the touch signals. The touch controller can also include a demodulation section for demodulating the received touch signals to obtain touch event results, where the touch controller can selectively adjust the demodulation section to reduce power during the demodulation of the touch signals. The touch controller can also selectively reduce power below present low levels during idle periods. The touch controller can be incorporated into a touch sensitive device.
    Type: Grant
    Filed: September 8, 2016
    Date of Patent: March 5, 2019
    Assignee: Apple Inc.
    Inventors: Christoph H. Krah, Thomas James Wilson
  • Patent number: 10191576
    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: Grant
    Filed: February 3, 2017
    Date of Patent: January 29, 2019
    Assignee: Apple Inc.
    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
  • Patent number: 10175830
    Abstract: A method for pre-charging a display panel may include simultaneously charging the display panel that displays image data and receives one or more touch inputs via a first voltage source and a capacitor that provides a first voltage to the display panel via a second voltage source. The first voltage is associated with receiving the one or more touch inputs, and the display panel and the capacitor are simultaneously charged for a first amount of time. The method may then include charging the display panel via the capacitor after the first amount of time for a second amount of time and charging the display panel via the second voltage source after the second amount of time for a third amount of time.
    Type: Grant
    Filed: September 30, 2015
    Date of Patent: January 8, 2019
    Assignee: Apple Inc.
    Inventors: Taif A. Syed, Kingsuk Brahma, Christoph H. Krah
  • Publication number: 20180364841
    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 24, 2018
    Publication date: December 20, 2018
    Inventors: Shahrooz SHAHPARNIA, Christoph H. KRAH
  • Patent number: 10152187
    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: June 19, 2017
    Date of Patent: December 11, 2018
    Assignee: Apple Inc.
    Inventor: Christoph H. Krah
  • Publication number: 20180348957
    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: Application
    Filed: August 6, 2018
    Publication date: December 6, 2018
    Applicant: Apple Inc.
    Inventors: Thomas James WILSON, Christoph H. KRAH, Minh-Dieu Thi VU
  • 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
  • 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
  • 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