Patents by Inventor Horace C. Ho

Horace C. Ho 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: 9386668
    Abstract: Intelligent illumination device are disclosed that use components in an LED light to perform one or more of a wide variety of desirable lighting functions for very low cost. The LEDs that produce light can be periodically turned off momentarily, for example, for a duration that the human eye cannot perceive, in order for the light to receive commands optically. The optically transmitted commands can be sent to the light, for example, using a remove control device. The illumination device can use the LEDs that are currently off to receive the data and then configure the light accordingly, or to measure light. Such light can be ambient light for a photosensor function, or light from other LEDs in the illumination device to adjust the color mix.
    Type: Grant
    Filed: December 17, 2014
    Date of Patent: July 5, 2016
    Assignee: Ketra, Inc.
    Inventors: David J. Knapp, Horace C. Ho, Jason Lewis
  • Patent number: 9345097
    Abstract: A method and illumination device are provided for interference-resistant compensation in light emitting diode (LED) illumination devices. In one embodiment, the method includes bringing to a level insufficient to produce illumination the respective drive current of all except one of multiple emission LED elements for the duration of a first measurement interval and a later-occurring second measurement interval. The first and second measurement intervals are within respective first and second series of measurement intervals interspersed with periods of illumination, and the first and second series of measurement intervals are separated by respective first and second offsets from a timing reference. An embodiment of an illumination device includes multiple emission LED elements, one or more photodetectors, and a lamp control circuit, where the lamp control circuit is adapted to perform steps of the method.
    Type: Grant
    Filed: October 9, 2014
    Date of Patent: May 17, 2016
    Assignee: Ketra, Inc.
    Inventors: Horace C. Ho, Rebecca Frank
  • Patent number: 9332598
    Abstract: A method and light emitting diode (LED) illumination device comprising multiple emitter modules are provided. In one embodiment, the method includes bringing to a level insufficient to produce illumination the respective drive currents of all except one of multiple emission LED elements within respective first and second emitter modules for the duration of a measurement interval within respective first and second series of measurement intervals. The measurement intervals are interspersed with periods of illumination, and the first and second series of measurement intervals are separated by respective first and second offsets from a timing reference. An embodiment of an illumination device includes multiple emitter modules, where each emitter module includes multiple emission LED elements and one or more photodetectors. The illumination device further includes a lamp control circuit adapted to perform steps of the method.
    Type: Grant
    Filed: October 9, 2014
    Date of Patent: May 3, 2016
    Assignee: Ketra, Inc.
    Inventors: Horace C. Ho, Rebecca Frank
  • Patent number: 9247605
    Abstract: A method and illumination device are provided for interference-resistant compensation in light emitting diode (LED) devices. In one embodiment, the method includes monitoring a detection photocurrent within a lamp during multiple detection intervals interspersed with periods of illumination, applying a drive current sufficient to produce illumination to one of multiple emission LED elements within the lamp during a subsequent measurement interval, and monitoring a measurement photocurrent within the lamp while the drive current is applied. An embodiment of an illumination device comprising a lamp includes multiple emission LED elements, one or more photodetectors, and a lamp control circuit, where the lamp control circuit is adapted to perform steps of the method.
    Type: Grant
    Filed: October 9, 2014
    Date of Patent: January 26, 2016
    Assignee: Ketra, Inc.
    Inventors: Horace C. Ho, Rebecca Frank
  • Patent number: 9237620
    Abstract: An illumination device comprising a plurality of light emitting diodes (LEDs) and a method for controlling the illumination device, so as to maintain a desired luminous flux and/or a desired color point of the device over variations in temperature and process, is provided herein. According to one embodiment, the method may include measuring a forward voltage developed across a first LED of the illumination device upon applying a first drive current to the first LED, determining a drive current needed to achieve a desired luminous flux from the first LED using the measured forward voltage, a table of stored calibration values correlating forward voltage and drive current to luminous flux at a plurality of different temperatures, and one or more interpolation techniques, and driving the first LED with the determined drive current to produce illumination having the desired luminous flux. The steps of measuring, determining and driving may be performed for each of the plurality of LEDs.
    Type: Grant
    Filed: August 20, 2013
    Date of Patent: January 12, 2016
    Assignee: Ketra, Inc.
    Inventors: David J. Knapp, Horace C. Ho, Joseph A. Savage
  • Publication number: 20150377699
    Abstract: An illumination device and method is provided herein for calibrating individual LEDs in the illumination device, so as to obtain a desired luminous flux and a desired chromaticity of the device over changes in drive current, temperature, and over time as the LEDs age. The calibration method may include subjecting the illumination device to a first ambient temperature, successively applying at least three different drive currents to a first LED to produce illumination at three or more different levels of brightness, obtaining a plurality of optical measurements from the illumination produced by the first LED at each of the at least three different drive currents, obtaining a plurality of electrical measurements from the photodetector and storing results of the obtaining steps within the illumination device to calibrate the first LED at the first ambient temperature.
    Type: Application
    Filed: June 25, 2014
    Publication date: December 31, 2015
    Inventors: Horace C. Ho, Jason E. Lewis, David J. Knapp
  • Publication number: 20150382422
    Abstract: An illumination device and method is provided herein for controlling individual light emitting diodes (LEDs) in an LED illumination device, so that a desired luminous flux and a desired chromaticity of the device can be maintained over time as the LEDs age. According to one embodiment, the method comprises applying drive currents to a plurality of LED chains substantially continuously to produce illumination, measuring a photocurrent induced on the photodetector in response to the illumination produced by each LED chain, one LED chain at a time, and received by the photodetector, and measuring a forward voltage developed across the photodetector by applying a non-operative drive current to the photodetector.
    Type: Application
    Filed: June 25, 2014
    Publication date: December 31, 2015
    Inventors: Horace C. Ho, Jason E. Lewis, David J. Knapp
  • Publication number: 20150377695
    Abstract: An illumination device comprises one or more emitter modules having improved thermal and electrical characteristics. According to one embodiment, each emitter module comprises a plurality of light emitting diodes (LEDs) configured for producing illumination for the illumination device, one or more photodetectors configured for detecting the illumination produced by the plurality of LEDs, a substrate upon which the plurality of LEDs and the one or more photodetectors are mounted, wherein the substrate is configured to provide a relatively high thermal impedance in the lateral direction, and a relatively low thermal impedance in the vertical direction, and a primary optics structure coupled to the substrate for encapsulating the plurality of LEDs and the one or more photodetectors within the primary optics structure.
    Type: Application
    Filed: June 25, 2014
    Publication date: December 31, 2015
    Inventors: Kuo-Lih Chang, Mickey Malone, Horace C. Ho
  • Publication number: 20150382425
    Abstract: An illumination device described herein includes at least a phosphor converted LED, which is configured for emitting illumination for the illumination device, a first photodetector and a second photodetector. A spectrum of the illumination emitted from the phosphor converted LED comprises a first portion having a first peak emission wavelength and a second portion having a second peak emission wavelength, which differs from the first peak emission wavelength. The first photodetector has a detection range, which is configured for detecting only the first portion of the spectrum emitted by the phosphor converted LED. The second photodetector has a detection range, which is configured for detecting only the second portion of the spectrum emitted by the phosphor converted LED. Methods are provided herein for calibrating and controlling each portion of the phosphor converted LED spectrum, as if the phosphor converted LED were two separate LEDs.
    Type: Application
    Filed: June 25, 2014
    Publication date: December 31, 2015
    Inventors: Jason E. Lewis, Horace C. Ho, David J. Knapp
  • Patent number: 9155155
    Abstract: A method and illumination device are provided for interference-resistant compensation in light emitting diode (LED) devices. In one embodiment, the method includes initiating a sequence of measurements during multiple measurement intervals interspersed with periods of illumination. The sequence of measurements includes sensitive measurements performed during measurement intervals when a non-constant external illumination is not present, and at least one non-sensitive measurement performed during an interval when non-constant external illumination is present. An embodiment of an illumination device comprising a lamp includes multiple emission LED elements, one or more photodetectors, a storage medium adapted for storing configuration information, and a lamp control circuit.
    Type: Grant
    Filed: October 9, 2014
    Date of Patent: October 6, 2015
    Assignee: Ketra, Inc.
    Inventors: Horace C. Ho, Rebecca Frank
  • Publication number: 20150102733
    Abstract: Intelligent illumination device are disclosed that use components in an LED light to perform one or more of a wide variety of desirable lighting functions for very low cost. The LEDs that produce light can be periodically turned off momentarily, for example, for a duration that the human eye cannot perceive, in order for the light to receive commands optically. The optically transmitted commands can be sent to the light, for example, using a remove control device. The illumination device can use the LEDs that are currently off to receive the data and then configure the light accordingly, or to measure light. Such light can be ambient light for a photosensor function, or light from other LEDs in the illumination device to adjust the color mix.
    Type: Application
    Filed: December 17, 2014
    Publication date: April 16, 2015
    Inventors: David J. Knapp, Horace C. Ho, Jason Lewis
  • Patent number: 8885478
    Abstract: A communication system, network, interface, and port architecture are provided for transporting data across a network. The network can be arranged by connecting the ports in a daisy chain fashion to achieve a ring architecture or topology. The network forwards data according to a specific network protocol. A first port forwards frames having a preemptive acknowledge field before the payload. A second port receives these frames, stores them in a frame buffer and modifies the preemptive acknowledge field according to its available frame buffer capacity. Said first port controls its data flow according to the modified preemptive acknowledge field.
    Type: Grant
    Filed: August 18, 2008
    Date of Patent: November 11, 2014
    Assignee: SMSC Europe GmbH
    Inventors: Rainer P. Mueller, Horace C. Ho, Patrick Heck, David Knapp, Kevin Rolfes
  • Patent number: 8521035
    Abstract: Systems and methods for visible light communication are disclosed. In part, illumination devices and related systems and methods are disclosed that can be used for general illumination, lighting control systems, or other applications. The illumination devices synchronize preferentially to the AC mains to produce time division multiplexed channels in which control information can be communicated optically by the same light source that is producing illumination. Such illumination devices preferentially comprise LEDs for producing illumination, transmitting data, detecting ambient light, and receiving data, however, other light sources and detectors can be used. The physical layer can be used with a variety of protocols, such as ZigBee, from the Media ACcess (MAC) layer and higher.
    Type: Grant
    Filed: August 5, 2010
    Date of Patent: August 27, 2013
    Assignee: Ketra, Inc.
    Inventors: David J. Knapp, Horace C. Ho
  • Publication number: 20130183042
    Abstract: A system, remote control device and method are provided herein for communicating with and controlling various devices using visible light communication (VLC). According to one embodiment, a method is provided for extending a communication range of a visible light communication system comprising a remote control device and a plurality of controlled devices. Such a method may include, for example, transmitting a communication message from a remote control device to a first controlled device located within range of the remote control device, wherein the communication message is transmitted through free space using visible light, and extending the communication range of the visible light communication system to a second controlled device, which is located outside of the range of the remote control device, by using the first controlled device to retransmit the communication message through free space using visible light to the second controlled device.
    Type: Application
    Filed: February 21, 2013
    Publication date: July 18, 2013
    Inventors: David J. Knapp, Horace C. Ho
  • Publication number: 20120001567
    Abstract: Intelligent illumination device are disclosed that use components in an LED light to perform one or more of a wide variety of desirable lighting functions for very low cost. The LEDs that produce light can be periodically turned off momentarily, for example, for a duration that the human eye cannot perceive, in order for the light to receive commands optically. The optically transmitted commands can be sent to the light, for example, using a remove control device. The illumination device can use the LEDs that are currently off to receive the data and then configure the light accordingly, or to measure light. Such light can be ambient light for a photosensor function, or light from other LEDs in the illumination device to adjust the color mix.
    Type: Application
    Filed: September 13, 2011
    Publication date: January 5, 2012
    Applicant: FIREFLY GREEN TECHNOLOGIES, INC.
    Inventors: David J. Knapp, Horace C. Ho, Jason Lewis
  • Publication number: 20110069960
    Abstract: Systems and methods for visible light communication are disclosed. In part, illumination devices and related systems and methods are disclosed that can be used for general illumination, lighting control systems, or other applications. The illumination devices synchronize preferentially to the AC mains to produce time division multiplexed channels in which control information can be communicated optically by the same light source that is producing illumination. Such illumination devices preferentially comprise LEDs for producing illumination, transmitting data, detecting ambient light, and receiving data, however, other light sources and detectors can be used. The physical layer can be used with a variety of protocols, such as ZigBee, from the Media ACcess (MAC) layer and higher.
    Type: Application
    Filed: August 5, 2010
    Publication date: March 24, 2011
    Inventors: David J. Knapp, Horace C. Ho
  • Patent number: 7634694
    Abstract: A communication system for transmitting and receiving a sequence of bits, and the methodology for transferring that sequence of bits are provided. The communication system includes a transmitting circuit and a receiving circuit. Within the transmitting circuit is a scrambler that comprises a shift register, an enable circuit, and an output circuit. The shift register temporarily stores n bits within the sequence of bits, and the enable circuit enables the shift register to store bits that arise only within the payload section of a frame. The output circuit includes a feedback, and several taps within the n stages to scramble logic values within the sequence of n bits output from the shift registers thus effectively preventing in most instances the sequence of bits from exceeding n number of the same logic value. Within the receiving circuit is a descrambler also having a shift register, an enable circuit, and an output circuit. The descrambler recompiles the scrambled data back to its original form.
    Type: Grant
    Filed: October 15, 2004
    Date of Patent: December 15, 2009
    Assignee: Standard Microsystems Corporation
    Inventors: Christopher M. Green, David J. Knapp, Horace C. Ho
  • Publication number: 20090080462
    Abstract: A communication system, network, interface, and port architecture are provided for transporting data across a network. The network can be arranged by connecting the ports in a daisy chain fashion to achieve a ring architecture or topology. The network forwards data according to a specific network protocol. A first port forwards frames having a preemptive acknowledge field before the payload. A second port receives these frames, stores them in a frame buffer and modifies the preemptive acknowledge field according to its available frame buffer capacity. Said first port controls its data flow according to the modified preemptive acknowledge field.
    Type: Application
    Filed: August 18, 2008
    Publication date: March 26, 2009
    Applicant: SMSC EUROPE GmbH
    Inventors: Rainer P. Mueller, Horace C. Ho, Patrick Heck, David Knapp, Kevin Rolfes
  • Patent number: 7283564
    Abstract: A communication system, network interface, and communication port is provided for interconnecting a network of multimedia devices. The multimedia devices can send streaming and/or non-streaming data across the network. The network accommodates all such types of data and assigns data types to time slots or frame segments within each frame to ensure streaming data maintains its temporal relationship at the receiver consistent with the transmitter. A first coding violation is used to indicate the beginning of asynchronous or isochronous data placed within a segment reserved for such data. A second coding violation within the data stream may also be used to signify the end of the isochronous or asynchronous message or data transfer within that segment. Alternatively, a message length code may be placed within the first coding violation to signify how many valid packets of data will follow in lieu of, for example, using a second coding violation within the data stream sometime after the first coding violation.
    Type: Grant
    Filed: June 26, 2002
    Date of Patent: October 16, 2007
    Assignee: Standard Microsystems Corp.
    Inventors: David J. Knapp, Horace C. Ho
  • Patent number: 7164691
    Abstract: A communication system, network interface, and communication port is provided for interconnecting a network of multimedia devices. The multimedia devices can send streaming and/or non-streaming data across the network. The network accommodates all such types of data and assigns data types to time slots or frame segments within each frame to ensure streaming data maintains its temporal relationship at the receiver consistent with the transmitter. A coding violation within a frame segment of one or more frames is used to indicate the absence of isochronous streaming data within the byte locations containing the coding violations. Coding violations can, therefore, be interspersed between isochronous data messages or data transfers to note that a particular portion of a frame segment does not contain isochronous data.
    Type: Grant
    Filed: June 26, 2002
    Date of Patent: January 16, 2007
    Assignee: Standard Microsystems Corporation
    Inventors: David J. Knapp, Horace C. Ho