Patents by Inventor Lap Chi (David) Leung

Lap Chi (David) Leung 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: 11448373
    Abstract: One example embodiment is a photosensitive candle comprising: (a) a candle container comprising an opening; (b) a candle component disposed in the candle container, comprising: a candle body having a surface proximate to or substantially aligned with the opening; a wick with an exposed portion protruding out of the surface of the candle body; and an optical fiber embedded in the candle body and positioned juxtapose to the wick for transmitting flame lights of the wick, wherein the optical fiber comprises a first end proximate to the exposed portion of the wick and an opposing second end; (c) a lighting control component disposed in the candle container, comprising: a casing comprising an interior cavity; a controller and a power source disposed within the interior cavity; and a light sensor connected to the controller, comprising a photosensitive element proximate to the second end of the optical fiber to detect light transmitted therefrom; and (d) at least one light-emitting device connected to the controlle
    Type: Grant
    Filed: August 20, 2021
    Date of Patent: September 20, 2022
    Inventor: Lap Chi Chan
  • Patent number: 8258852
    Abstract: A motor driver circuit for driving the gate node of a high-side driver transistor to a boosted voltage from a charge pump draws little or no static current from the charge pump. The gate node is pulled to the boosted voltage by a p-channel pullup-control transistor that is driven by p-channel transistors that are pumped by capacitors that cut off current flow to ground from the charge pump. An n-channel output-shorting transistor shorts the gate node to the output when the high-side driver is turned off. A coupling capacitor initializes the shorting transistor for each output transition. A p-channel output-sensing transistor generates a feedback to a second stage that drives the coupling capacitor. P-channel diode transistors and an n-channel equalizing transistor control the voltage on the coupling capacitor.
    Type: Grant
    Filed: November 18, 2010
    Date of Patent: September 4, 2012
    Assignee: Hong Kong Applied Science and Technology Research Institute Co., Ltd.
    Inventors: Lap Chi David Leung, Yat Tung Lai, Chun Fai Wong, Kam Hung Chan, Kwok Kuen David Kwong
  • Publication number: 20120126736
    Abstract: A motor driver circuit for driving the gate node of a high-side driver transistor to a boosted voltage from a charge pump draws little or no static current from the charge pump. The gate node is pulled to the boosted voltage by a p-channel pullup-control transistor that is driven by p-channel transistors that are pumped by capacitors that cut off current flow to ground from the charge pump. An n-channel output-shorting transistor shorts the gate node to the output when the high-side driver is turned off. A coupling capacitor initializes the shorting transistor for each output transition. A p-channel output-sensing transistor generates a feedback to a second stage that drives the coupling capacitor. P-channel diode transistors and an n-channel equalizing transistor control the voltage on the coupling capacitor.
    Type: Application
    Filed: November 18, 2010
    Publication date: May 24, 2012
    Applicant: Hong Kong Applied Science & Technology Research Institute Company Limited
    Inventors: Lap Chi (David) LEUNG, Yat Tung LAI, Chun Fai WONG, Kam Hung CHAN, Kwok Kuen KWONG
  • Patent number: 8179455
    Abstract: A Optical Black Pixel (OBP) cancellation circuit corrects offsets in sensors in a CCD/CMOS image sensor when reading dark pixels such at the periphery. A pixel voltage is switched to a sampling capacitor during two phases of the same pixel pulse. Sampling capacitors and feedback capacitors connect to differential inputs of an amplifier. An accumulating capacitor accumulates voltage differences and generates a common-mode voltage that is fed back to another sampling capacitor that stores an amplifier offset. The sampling capacitor and accumulating capacitor and their associated switches form a discrete-time first-order low-pass filter that filters the pixel voltage during the first phase. In the second phase the amplifier acts as a unity-gain amplifier to output an average of the pixel voltage differences generated during an OBP time when blackened or covered pixels are read from the image sensor.
    Type: Grant
    Filed: March 11, 2010
    Date of Patent: May 15, 2012
    Assignee: Hong Kong Applied Science and Technology Research Institute Co., Ltd.
    Inventors: Lap Chi (David) Leung, Yat Tung Lai, Chun Fai Wong, Kam Hung Chan, Kwok Kuen (David) Kwong
  • Publication number: 20110221938
    Abstract: A Optical Black Pixel (OBP) cancellation circuit corrects offsets in sensors in a CCD/CMOS image sensor when reading dark pixels such at the periphery. A pixel voltage is switched to a sampling capacitor during two phases of the same pixel pulse. Sampling capacitors and feedback capacitors connect to differential inputs of an amplifier. An accumulating capacitor accumulates voltage differences and generates a common-mode voltage that is fed back to another sampling capacitor that stores an amplifier offset. The sampling capacitor and accumulating capacitor and their associated switches form a discrete-time first-order low-pass filter that filters the pixel voltage during the first phase. In the second phase the amplifier acts as a unity-gain amplifier to output an average of the pixel voltage differences generated during an OBP time when blackened or covered pixels are read from the image sensor.
    Type: Application
    Filed: March 11, 2010
    Publication date: September 15, 2011
    Applicant: Hong Kong Applied Science & Technology Research Institute Company Limited
    Inventors: Lap Chi (David) LEUNG, Yat Tung LAI, Chun Fai WONG, Kam Hung CHAN, Kwok Kuen (David) KWONG
  • Patent number: 7659780
    Abstract: A gain control circuit including a resistor with a first terminal and a second terminal; an operational amplifier with an inverting terminal thereof electrically coupled to said first terminal of said resistor; a non-inverting terminal thereof; and an output terminal thereof; an amplifier circuit for transforming the voltage change of said operational amplifier output into a substantially exponential current change; wherein the output of said amplifier circuit is electrically coupled to said inverting terminal of said operational amplifier. The above described gain control circuit is able to perform wide bandwidth input signal buffering with linearity under low voltage and low power conditions. The circuit also offers low output impedances without the need of additional buffers and hence minimizing circuit size and manufacturing costs.
    Type: Grant
    Filed: November 29, 2007
    Date of Patent: February 9, 2010
    Assignee: Hong Kong Applied Science and Technology Research Institute Co., Ltd.
    Inventors: Chit Ah Mak, Chun Fai Wong, Lap Chi Leung, Xiaofei Kuang, Jennifer Shuet Yan Ho, David Kwok Kuen Kwong
  • Publication number: 20090140808
    Abstract: A gain control circuit including a resistor with a first terminal and a second terminal; an operational amplifier with an inverting terminal thereof electrically coupled to said first terminal of said resistor; a non-inverting terminal thereof; and an output terminal thereof; an amplifier circuit for transforming the voltage change of said operational amplifier output into a substantially exponential current change; wherein the output of said amplifier circuit is electrically coupled to said inverting terminal of said operational amplifier. The above described gain control circuit is able to perform wide bandwidth input signal buffering with linearity under low voltage and low power conditions. The circuit also offers low output impedances without the need of additional buffers and hence minimizing circuit size and manufacturing costs.
    Type: Application
    Filed: November 29, 2007
    Publication date: June 4, 2009
    Applicant: Hong Kong Applied Science and Technology Research Institute Company Limited
    Inventors: Chit Ah MAK, Chun Fai WONG, Lap Chi LEUNG, Xiaofei KUANG, Jennifer Shuet Yan HO, David Kwok Kuen KWONG