Patents by Inventor WOOI KIP LIM

WOOI KIP LIM 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: 11750941
    Abstract: An imaging circuit includes plural pixel circuits which are arranged in a pixel array. Each of the plural pixel circuits includes an image sensing device which is configured to sense a normal imaging light shedding on the imaging circuit with a predetermined frame rate. At least a portion of the plural pixel circuits are first type pixel circuits. Each of the first type pixel circuit further includes a flicker sensing device. Plural flicker sensing devices in the pixel array are coupled in parallel to sense a flickering light shedding on the imaging circuit to generate a flicker indicating signal.
    Type: Grant
    Filed: May 5, 2022
    Date of Patent: September 5, 2023
    Assignee: PIXART IMAGING INCORPORATION
    Inventors: Wooi-Kip Lim, Shan-Chong Tan
  • Patent number: 11683608
    Abstract: An image sensor device includes a sensor array and a processing circuit. The sensor array includes a plurality of pixel units each including a photodiode unit and a storage capacitor. The sensor array generates an image of a specific frame, and the photodiode unit is illuminated by a light ray to generate a photodiode current which is stored in the storage capacitor when the image sensor device performs an exposure operation. The processing circuit generates a reference current according to photodiode current(s) of photodiode unit(s) of pixel unit(s) before the exposure operation arranged for the specific frame starts, and predicts a length of an exposure time interval of the exposure operation for the specific frame based on the generated reference current.
    Type: Grant
    Filed: July 1, 2021
    Date of Patent: June 20, 2023
    Assignee: PixArt Imaging Inc.
    Inventor: Wooi Kip Lim
  • Patent number: 11622176
    Abstract: An image sensor comprising a BJT pixel circuit, a biasing circuit and a comparator. The BJT pixel circuit comprises a BJT; a charging selection circuit, configured to control a first storage capacitor to be charged in a first reset time and to control a second storage capacitor to be charged to a second reset time; a discharging selection circuit, configured to control the first storage capacitor to be discharged by the BJT in a first exposure time to generate a first output voltage, and to control the second storage capacitor to be discharged by the BJT in a second exposure time to generate a second output voltage; a biasing circuit, configured to provide voltage decreasing and voltage increasing to the second output voltage to generated adjusted images; and a comparator, configured to compare the first output voltage and the adjusted voltages.
    Type: Grant
    Filed: January 10, 2022
    Date of Patent: April 4, 2023
    Assignee: PixArt Imaging Inc.
    Inventor: Wooi Kip Lim
  • Publication number: 20230007201
    Abstract: An image sensor device includes a sensor array and a processing circuit. The sensor array includes a plurality of pixel units each including a photodiode unit and a storage capacitor. The sensor array generates an image of a specific frame, and the photodiode unit is illuminated by a light ray to generate a photodiode current which is stored in the storage capacitor when the image sensor device performs an exposure operation. The processing circuit generates a reference current according to photodiode current(s) of photodiode unit(s) of pixel unit(s) before the exposure operation arranged for the specific frame starts, and predicts a length of an exposure time interval of the exposure operation for the specific frame based on the generated reference current.
    Type: Application
    Filed: July 1, 2021
    Publication date: January 5, 2023
    Applicant: PixArt Imaging Inc.
    Inventor: Wooi Kip Lim
  • Patent number: 11290666
    Abstract: An image sensor uses a pixel circuit which includes a BJT phototransistor having multiple selectable beta values. The BJT is one semiconductor device includes: a substrate having a first conductivity type; a first well having the first conductivity type; a collector electrode having the first conductivity type in the first well; a second well having a first concentration of a second conductivity type; a first emitter electrode having the first conductivity type in the second well; a base electrode having the second conductivity type in the second well; a third well having a second concentration of the second conductivity type, wherein the second concentration is different from the first concentration; and a second emitter electrode having the first conductivity type in the third well.
    Type: Grant
    Filed: May 20, 2020
    Date of Patent: March 29, 2022
    Assignee: PIXART IMAGING INCORPORATION
    Inventors: Wooi-Kip Lim, Shan-Chong Tan
  • Patent number: 11287901
    Abstract: An optical detecting device capable of detecting a lift height of an optical navigation apparatus is disclosed. The optical detecting device includes a sensor module and a processor. The sensor module includes a sensor array and at least one detector strip. The sensor array is adapted to acquire navigation information of the optical navigation apparatus moved relative to a working surface by sensing an illumination area, and the detector strip has a detection region across an edge of the illumination area. The processor is electrically connected to the sensor module, and adapted to compute the lift height of the optical navigation apparatus relative to the working surface according to a detection result of the detector strip.
    Type: Grant
    Filed: November 13, 2019
    Date of Patent: March 29, 2022
    Assignee: PixArt Imaging Inc.
    Inventors: Kwai Lee Pang, Wooi Kip Lim, Siew Chin Lee
  • Patent number: 11282888
    Abstract: A bipolar junction transistor (BJT) pixel circuit, including: a BJT transistor, having a base coupled to a photo detector, an emitter coupled to a shutter circuit, and a collector coupled to a reference ground level; the photo detector, having first end coupled to the base of BJT transistor and second end coupled to the reference ground level, for generating base current based on light intensity of light incident on the photo detector; the shutter circuit, coupled to the emitter of the BJT transistor, for controlling exposure time of the photo detector according to a shutter signal; and a storage capacitor, coupled between the shutter circuit and an adjustable ground level different from the reference ground level, for storing image data captured by the photo detector, wherein the adjustable ground level is boosted to be higher than the reference ground level for one or more times during the exposure time.
    Type: Grant
    Filed: August 26, 2020
    Date of Patent: March 22, 2022
    Assignee: Pix Art Imaging Inc.
    Inventor: Wooi Kip Lim
  • Publication number: 20220068993
    Abstract: A bipolar junction transistor (BJT) pixel circuit, including: a BJT transistor, having a base coupled to a photo detector, an emitter coupled to a shutter circuit, and a collector coupled to a reference ground level; the photo detector, having first end coupled to the base of BJT transistor and second end coupled to the reference ground level, for generating base current based on light intensity of light incident on the photo detector; the shutter circuit, coupled to the emitter of the BJT transistor, for controlling exposure time of the photo detector according to a shutter signal; and a storage capacitor, coupled between the shutter circuit and an adjustable ground level different from the reference ground level, for storing image data captured by the photo detector, wherein the adjustable ground level is boosted to be higher than the reference ground level for one or more times during the exposure time.
    Type: Application
    Filed: August 26, 2020
    Publication date: March 3, 2022
    Inventor: Wooi Kip LIM
  • Publication number: 20210368113
    Abstract: An image sensor uses a pixel circuit which includes a BJT phototransistor having multiple selectable beta values. The BJT is one semiconductor device includes: a substrate having a first conductivity type; a first well having the first conductivity type; a collector electrode having the first conductivity type in the first well; a second well having a first concentration of a second conductivity type; a first emitter electrode having the first conductivity type in the second well; a base electrode having the second conductivity type in the second well; a third well having a second concentration of the second conductivity type, wherein the second concentration is different from the first concentration; and a second emitter electrode having the first conductivity type in the third well.
    Type: Application
    Filed: May 20, 2020
    Publication date: November 25, 2021
    Inventors: Wooi-Kip Lim, Shan-Chong Tan
  • Patent number: 11050956
    Abstract: An image sensor includes a transistor, at least one storage capacitor and a voltage provider. The at least one storage capacitor is connected to the transistor. The voltage provider is electrically connected to the transistor and configured to provide an extra voltage for the at least one storage capacitor. The extra voltage is variable in response to images with different brightness. The image sensor includes the voltage provider to provide extra voltage to increase the charging capacity of the storage capacitor. The Signal-Noise-Ratio of the image sensor won't be affected and the fill factor is able to be maintained at a certain level.
    Type: Grant
    Filed: March 29, 2019
    Date of Patent: June 29, 2021
    Assignee: PIXART IMAGING INC.
    Inventor: Wooi-Kip Lim
  • Publication number: 20210141465
    Abstract: An optical detecting device capable of detecting a lift height of an optical navigation apparatus is disclosed. The optical detecting device includes a sensor module and a processor. The sensor module includes a sensor array and at least one detector strip. The sensor array is adapted to acquire navigation information of the optical navigation apparatus moved relative to a working surface by sensing an illumination area, and the detector strip has a detection region across an edge of the illumination area. The processor is electrically connected to the sensor module, and adapted to compute the lift height of the optical navigation apparatus relative to the working surface according to a detection result of the detector strip.
    Type: Application
    Filed: November 13, 2019
    Publication date: May 13, 2021
    Inventors: Kwai Lee PANG, Wooi Kip LIM, Siew Chin LEE
  • Publication number: 20200314366
    Abstract: An image sensor includes a transistor, at least one storage capacitor and a voltage provider. The at least one storage capacitor is connected to the transistor. The voltage provider is electrically connected to the transistor and configured to provide an extra voltage for the at least one storage capacitor. The extra voltage is variable in response to images with different brightness. The image sensor includes the voltage provider to provide extra voltage to increase the charging capacity of the storage capacitor. The Signal-Noise-Ratio of the image sensor won't be affected and the fill factor is able to be maintained at a certain level.
    Type: Application
    Filed: March 29, 2019
    Publication date: October 1, 2020
    Inventor: WOOI-KIP LIM
  • Patent number: 10785436
    Abstract: An image sensor for capturing an image, includes: an array of pixel circuits, wherein each of the pixel circuits is for sensing a portion of the image, and generate a sample signal and a hold signal according to the portion of the image and a predetermined reset voltage respectively; and a transfer circuit, which is coupled to the array, and is for converting the sample signals and hold signals to corresponding digital sensing signals and corresponding digital reset signals respectively, to generate pixel signals respectively corresponding to the pixel circuits according to the digital sensing signals and the digital reset signals; wherein the transfer circuit converts the sample signal generated by one of the pixel circuits to the corresponding digital sensing signal and converts the hold signal generated by another one of the pixel circuits to the corresponding digital reset signal at least partially within a same period.
    Type: Grant
    Filed: September 11, 2019
    Date of Patent: September 22, 2020
    Assignee: PIXART IMAGING INCORPORATION
    Inventor: Wooi-Kip Lim
  • Patent number: 10613155
    Abstract: A short circuit testing method for a capacitive sensing device including a plurality of sense lines and a plurality of drive lines includes: under a short circuit testing mode, coupling at least one first line in the sense lines and drive lines to a reference level; using a sensing circuit corresponding to a specific sense line to read out a testing resultant signal; and, comparing the testing resultant signal with a reference signal to determine whether a short circuit exists.
    Type: Grant
    Filed: October 31, 2017
    Date of Patent: April 7, 2020
    Assignee: PixArt Imaging Inc.
    Inventors: Sung-Han Wu, Wooi Kip Lim, Kei Tee Tiew, Keen-Hun Leong
  • Patent number: 10613686
    Abstract: A signal processing circuit of a touch device including an operational amplifier, a feedback resistor and a step current circuit is provided. The feedback resistor connects between a negative input and an output terminal of the operational amplifier. The step current circuit is coupled to the negative input of the operational amplifier and configured to provide or draw a step current to reduce the current flowing through the feedback resistor so as to compensate the voltage offset of the operational amplifier.
    Type: Grant
    Filed: March 4, 2019
    Date of Patent: April 7, 2020
    Assignee: PIXART IMAGING INC.
    Inventor: Wooi-Kip Lim
  • Patent number: 10431623
    Abstract: A method applied to a BJT pixel of an image sensor apparatus includes: obtaining at least one of a surface quality signal of a first image sensed by the BJT pixel and a shutter turn-on time corresponding to the first image; and adaptively adjusting a pre-flash time of the BJT pixel for sensing of a second image according to the at least one of the surface quality signal of the first image and the shutter turn-on time corresponding to the first image; wherein the second image follows the first image.
    Type: Grant
    Filed: October 22, 2017
    Date of Patent: October 1, 2019
    Assignee: PixArt Imaging Inc.
    Inventor: Wooi Kip Lim
  • Patent number: 10374589
    Abstract: A temperature detecting circuit comprising: a comparator, comprising a first comparing terminal and a second comparing terminal; a time interval computing unit; a switch module, coupled to the first comparing terminal and the second comparing terminal, comprising a reference voltage terminal coupled to a reference voltage source, and comprising a first input terminal, a second input terminal and a third input terminal; a first current source, comprising a first charging terminal coupled to the first input terminal and the second input terminal; a first capacitor, coupled to the first current source at the first charging terminal; a capacitance adjusting unit, coupled to the first capacitor; a second current source, comprising a second charging terminal coupled to the third input terminal, wherein the second current source is a current source which provides a constant current; and a second capacitor, coupled to the second current source at the second charging terminal.
    Type: Grant
    Filed: September 19, 2018
    Date of Patent: August 6, 2019
    Assignee: PixArt Imaging Inc.
    Inventors: Wooi Kip Lim, Yong Yeap Tan
  • Patent number: 10359312
    Abstract: A device, for pixel transfer rate boosting, is provided and includes an image sensing array having a plurality of pixel units, in which each of the plurality of pixel units is configured to generate a pixel signal when receiving an electromagnetic energy, a signal buffer circuit, electrically coupled with the image sensing array to receive the pixel signals, a switch circuit electrically coupled with the signal buffer circuit, a capacitor having a first terminal and a second terminal, in which the first terminal electrically couples with the switch circuit and the second terminal connects to a ground, a comparator, electrically coupled with the switch circuit, and a pull-down unit, electrically coupled with the first terminal of the capacitor and the switch circuit. After the switch circuit is turned on, the pull-down unit pulls the plurality of pixel output signals down.
    Type: Grant
    Filed: August 28, 2017
    Date of Patent: July 23, 2019
    Assignee: PIXART IMAGING INC.
    Inventors: Wooi-Kip Lim, Han-Chi Liu
  • Publication number: 20190204988
    Abstract: A signal processing circuit of a touch device including an operational amplifier, a feedback resistor and a step current circuit is provided. The feedback resistor connects between a negative input and an output terminal of the operational amplifier. The step current circuit is coupled to the negative input of the operational amplifier and configured to provide or draw a step current to reduce the current flowing through the feedback resistor so as to compensate the voltage offset of the operational amplifier.
    Type: Application
    Filed: March 4, 2019
    Publication date: July 4, 2019
    Inventor: WOOI-KIP LIM
  • Publication number: 20190123091
    Abstract: A method applied to a BJT pixel of an image sensor apparatus includes: obtaining at least one of a surface quality signal of a first image sensed by the BJT pixel and a shutter turn-on time corresponding to the first image; and adaptively adjusting a pre-flash time of the BJT pixel for sensing of a second image according to the at least one of the surface quality signal of the first image and the shutter turn-on time corresponding to the first image; wherein the second image follows the first image.
    Type: Application
    Filed: October 22, 2017
    Publication date: April 25, 2019
    Inventor: Wooi Kip LIM