Patents Assigned to HIMAX IMAGING LIMITED
  • Patent number: 11063598
    Abstract: A phase-locked loop (PLL) includes a voltage-controlled oscillator (VCO) that generates a PLL output signal having an oscillation frequency controlled by a control signal; a phase detector that generates a phase signal representing a difference in phase between the PLL output signal and a reference signal; a loop filter coupled to receive the phase signal; a switch; and a sampling circuit switchably coupled to receive the control signal of the VCO via the switch, and generating a code representing the control signal.
    Type: Grant
    Filed: October 16, 2020
    Date of Patent: July 13, 2021
    Assignee: Himax Imaging Limited
    Inventors: Xufeng Bao, Hack Soo Oh, Youngchul Sohn, Amit Mittra
  • Patent number: 10917596
    Abstract: A pixel circuit is disclosed. The pixel circuit includes a photodiode (PD), a transmission circuit, a reset circuit, a signal storage circuit and a buffer circuit. The transmission circuit is coupled between the PD and an ordinary floating diffusion (FD) node. The reset circuit is coupled to the ordinary FD node. The signal storage circuit is coupled to the ordinary FD node. The buffer circuit is coupled to the signal storage circuit. The signal storage circuit may store a PD signal on a specific node having a reduced leakage path in comparison with the ordinary FD node during a holding phase of the pixel circuit, wherein the holding phase is a time interval starting from a first time point at which the PD signal is stored on the specific node and ending at a second time point at which the pixel circuit is selected for performing a read-out operation.
    Type: Grant
    Filed: November 6, 2018
    Date of Patent: February 9, 2021
    Assignee: Himax Imaging Limited
    Inventors: Hack soo Oh, Yu Hin Desmond Cheung, Kihong Kim
  • Patent number: 10890482
    Abstract: A pixel circuit is provided. The pixel circuit may comprise a photodiode, a comparator circuit, a capacitor, a first switch circuit, a second switch circuit and a third switch circuit. The photodiode is arranged to accumulate charges in response to incident radiation, to generate a photodiode signal. The comparator circuit is arranged to generate an output signal according to a voltage level of a specific node within the pixel circuit during a read-out phase of the pixel circuit. The capacitor is coupled between a control voltage terminal of the pixel circuit and the specific node, the first switch circuit is coupled between the photodiode and the specific node, the second switch circuit is coupled between the specific node and an output terminal of the pixel circuit, and the third switch circuit is coupled between the output terminal and the comparator circuit.
    Type: Grant
    Filed: January 18, 2019
    Date of Patent: January 12, 2021
    Assignee: Himax Imaging Limited
    Inventor: Hack soo Oh
  • Patent number: 10791291
    Abstract: A pixel circuit includes a front-end circuit, a signal storage circuit, and an output circuit. The signal storage circuit is coupled to the front-end circuit, and the output circuit is coupled to the signal storage circuit. The front-end circuit is arranged to generate pixel signals. The signal storage circuit is arranged to store the pixel signals generated by the front-end circuit, wherein when the pixel circuit is selected for performing a read-out operation, the pixel signals stored in the signal storage circuit are pulled up from original voltage levels to other voltage levels higher than the original voltage levels according to a voltage increment applied to a control voltage. When the pixel circuit is selected for performing the read-out operation, the output circuit generates output signals on an output terminal according to the other voltage levels, respectively.
    Type: Grant
    Filed: November 14, 2018
    Date of Patent: September 29, 2020
    Assignee: Himax Imaging Limited
    Inventors: Hack soo Oh, Yu Hin Desmond Cheung, Kihong Kim
  • Patent number: 10771725
    Abstract: A pixel circuit is provided, where the pixel circuit comprises a photodiode, a buffer circuit, a first capacitor, a first switch, a second switch and a third switch. The photodiode is configured to accumulate charges in response to incident radiation, to generate a photodiode signal. The buffer circuit is configured to output at least one read-out signal, wherein an input terminal of the buffer circuit is coupled to a specific node. The first capacitor is coupled between a control voltage terminal of the pixel circuit and the specific node. The first switch is coupled between the photodiode and the specific node. The second switch is coupled between the input terminal of the buffer circuit and an output terminal of the buffer circuit. The third switch is coupled between the output terminal of the buffer circuit and a read-out terminal of the pixel circuit.
    Type: Grant
    Filed: July 3, 2019
    Date of Patent: September 8, 2020
    Assignee: Himax Imaging Limited
    Inventor: Hack soo Oh
  • Patent number: 10750077
    Abstract: A camera system is provided and includes a processor, a first camera, a second camera, and a data bus. The processor transmits a first trigger signal to the first camera to enable the first camera outputting first data to the processor through the data bus. The first camera transmits a second trigger signal to the second camera to enable the second camera outputting second data to the processor through the data bus.
    Type: Grant
    Filed: February 20, 2019
    Date of Patent: August 18, 2020
    Assignee: Himax Imaging Limited
    Inventors: Amit Mittra, Tony Chiang
  • Patent number: 10721408
    Abstract: An automatic exposure (AE) imaging system includes an image sensor that captures an analog image; an analog-to-digital converter (ADC) that converts the analog image into a digital image; a single-frame image processor that processes the digital image; an exposure quantizer that generates a discrete number representing a determined exposure time according to an output of the single-frame image processor; a multi-exposure controller, under control of a motion-detect signal, generating a plurality of different exposure times in sequence in each frame period in a motion detection mode, and outputting the determined exposure time in a streaming mode; and a pixel controller coupled to receive an output of the multi-exposure controller, according to which the image sensor is controlled.
    Type: Grant
    Filed: December 26, 2018
    Date of Patent: July 21, 2020
    Assignee: Himax Imaging Limited
    Inventor: Youngchul Sohn
  • Patent number: 10630926
    Abstract: An anti-eclipse circuit for use in an imager includes a differential amplifier and a feedback circuit. The differential amplifier is coupled to an output line for receiving an output signal associated with the voltage level of a floating diffusion region in a pixel of the imager and configured to detect when a reset signal received from the pixel drops below a predetermined level. The feedback circuit is configured to increase the reset signal when the output signal is lower than the clamp voltage, thereby keeping the reset signal at the constant level.
    Type: Grant
    Filed: June 3, 2017
    Date of Patent: April 21, 2020
    Assignee: HIMAX IMAGING LIMITED
    Inventors: Youngchul Sohn, Kwangoh Kim, Amit Mittra
  • Patent number: 10595007
    Abstract: A structured-light (SL) method of dynamically generating a depth map includes moving a lens of an image capture device to a first position associated with first depth of field (DOF); capturing first reflected structured light with the first DOF, thereby resulting in a first image; processing the first image to generate a first depth map; moving the lens to a second position associated with second DOF, the second DOF being nearer the image capture device than the first DOF; capturing second reflected structured light with the second DOF, thereby resulting in a second image; processing the second image to generate a second depth map; and combining the first depth map and the second depth map to result in a combined depth map.
    Type: Grant
    Filed: March 21, 2018
    Date of Patent: March 17, 2020
    Assignees: Himax Imaging Limited, Himax Technologies Limited
    Inventors: Biing-Seng Wu, Yu-Yu Sung, Huan-Pin Tseng
  • Patent number: 10566368
    Abstract: A pixel structure of an image sensor is provided and includes following units. A crystalline layer of a first doping type is formed on a substrate. A photodiode region is formed in the crystalline layer. A gate of a source follower transistor is formed on a top surface of the crystalline layer. A reset gate is formed on the top surface of the crystalline layer. A doped region of a second doping type is formed in the crystalline layer and formed between the reset gate and the gate of the source follower. The first doping type is different from the second doping type, and the photodiode region is connected to the doped region under the top surface of the crystalline layer as an anti-blooming path.
    Type: Grant
    Filed: August 13, 2018
    Date of Patent: February 18, 2020
    Assignee: Himax Imaging Limited
    Inventors: Yang Wu, Fei-Xia Yu, Yu Hin Desmond Cheung
  • Patent number: 10498989
    Abstract: A digital double-sampling (DDS) circuit includes a comparator with input nodes respectively connected to a ramp voltage and an image output node of a pixel circuit via a capacitor; a reset switch connected between the input nodes for resetting the capacitor; an analog-to-digital converter (ADC) coupled to receive a comparison output of the comparator, the ADC including a counter that counts while the ramp voltage is ramping, thereby generating a reset-ADC value in a reset phase and generating a signal-ADC value in a signal phase; a subtractor that subtracts the reset-ADC value from the signal-ADC value, thereby resulting in a difference value representing a sampled output; and a clamp circuit that generates a clamp voltage at the image output node. In the reset phase, the clamp circuit is disabled after the capacitor finishes resetting but before the ramp voltage begins ramping.
    Type: Grant
    Filed: November 1, 2018
    Date of Patent: December 3, 2019
    Assignee: Himax Imaging Limited
    Inventors: Hack Soo Oh, Youngchul Sohn, Kwangoh Kim
  • Patent number: 10498972
    Abstract: A high-dynamic-range (HDR) imaging system includes a pixel array providing a high-sensitivity signal and a low-sensitivity signal; and an HDR encoder generating an encoded signal according to the high-sensitivity signal and the low-sensitivity signal. A flag bit is asserted when the high-sensitivity signal is not greater than a predetermined threshold, otherwise the flag bit is de-asserted.
    Type: Grant
    Filed: September 28, 2018
    Date of Patent: December 3, 2019
    Assignee: Himax Imaging Limited
    Inventor: Po-Chang Chen
  • Patent number: 10404928
    Abstract: The invention is directed to a method of operating an image sensor. A first integration is performed on a first photodiode of a pixel circuit to obtain at least one first image signal. A second integration is performed on a second photodiode of the pixel circuit to obtain a second image signal, the first photodiode having a photodiode area larger than the second photodiode. A third integration is performed by collecting blooming charge overflowing from the first photodiode to obtain an overflow image signal. The first integration has longest integration time and the third integration has shortest integration time among the first integration, the second integration and the third integration.
    Type: Grant
    Filed: July 6, 2017
    Date of Patent: September 3, 2019
    Assignee: Himax Imaging Limited
    Inventors: Yu Hin Desmond Cheung, Amit Mittra, Yang Wu
  • Patent number: 10389962
    Abstract: An image pickup apparatus includes an image sensor array, a scaling circuit, an output circuit and a timing control circuit. The image sensor array reads N pixel lines according to a read timing control signal to capture N lines of pixel data of a source image. The scaling circuit receives the N lines of pixel data according to a scaling timing control signal, and refers to a scaling factor to scale up the source image to generate an upscaled image having M lines of pixel data. M is a positive integer greater than N. The output circuit outputs the M lines of pixel data according to an output timing. The timing control circuit determines a receiving timing according to the output timing and the scaling factor to generate the scaling timing control signal, and determines a read timing according to the receiving timing to generate the read timing control signal.
    Type: Grant
    Filed: August 14, 2017
    Date of Patent: August 20, 2019
    Assignee: Himax Imaging Limited
    Inventors: Yuan-Chih Peng, Ching-Fong Chen
  • Patent number: 10163965
    Abstract: A photodiode (PD) of a complementary metal-oxide-semiconductor (CMOS) image sensor includes a top PD of a second type disposed in a first-type layer; and a bottom PD of the second type disposed in the first-type layer and below the top PD, the bottom PD including at least one sub-photodiode (sub-PD) of the second type connected to the top PD and at least one sub-well of the first type surrounded by the at least one sub-PD.
    Type: Grant
    Filed: June 21, 2017
    Date of Patent: December 25, 2018
    Assignee: Himax Imaging Limited
    Inventors: Yang Wu, Inna Patrick
  • Patent number: 10152070
    Abstract: An analog block implemented with a band-gap reference scheme for use in a device includes a mode control unit and a band-gap reference circuit. The mode control unit is configured to generate a mode selection signal associated with the operational mode of the device. The band-gap reference circuit includes a bias generator, an error amplifier, and a band-gap loop circuit. The bias generator is configured to provide a band-gap reference voltage in a first bias state when the device operates in a normal mode or in a second bias state when the device operates in a standby mode. The error amplifier is configured to generate an error voltage according to the bias voltage. The band-gap loop circuit is configured to provide a band-gap reference voltage according to the error voltage. First current flowing through the bias generator in the first bias state is larger than second current flowing through the bias generator in the second bias state.
    Type: Grant
    Filed: August 1, 2017
    Date of Patent: December 11, 2018
    Assignee: HIMAX IMAGING LIMITED
    Inventors: Youngchul Sohn, Kwangoh Kim, Amit Mittra
  • Publication number: 20180352180
    Abstract: An anti-eclipse circuit for use in an imager includes a differential amplifier and a feedback circuit. The differential amplifier is coupled to an output line for receiving an output signal associated with the voltage level of a floating diffusion region in a pixel of the imager and configured to detect when a reset signal received from the pixel drops below a predetermined level. The feedback circuit is configured to increase the reset signal when the output signal is lower than the clamp voltage, thereby keeping the reset signal at the constant level.
    Type: Application
    Filed: June 3, 2017
    Publication date: December 6, 2018
    Applicant: HIMAX IMAGING LIMITED
    Inventors: Youngchul SOHN, Kwangoh KIM, Amit MITTRA
  • Patent number: 10104321
    Abstract: An image processing system for an image sensor includes an analog-to-digital conversion (ADC) unit that performs ADC on pixel signals, thereby generating digital pixel signals; a correlated double sampling (CDS) unit that performs CDS on the digital pixel signals; a black level estimation (BLE) unit that generates a negative offset voltage according to dark voltage obtained from CDS performed on estimating optical black pixels (OBPs) of a pixel array, the negative offset voltage being subtracted from the pixel signals before feeding the pixel signals to the ADC unit; and a black level compensation (BLC) unit that performs BLC on active pixels sensors (APSs) and the compensating OBPs of the pixel array.
    Type: Grant
    Filed: August 15, 2017
    Date of Patent: October 16, 2018
    Assignee: Himax Imaging Limited
    Inventors: Youngchul Sohn, Kwangoh Kim, Hack soo Oh
  • Patent number: 9871972
    Abstract: An auto exposure control system includes a mean statistics unit that generates a weighted mean brightness value for an image array; a target control unit that determines a target brightness value according to an ambient status that is determined in accordance with an ambient light value, wherein, in one embodiment, the weighted mean brightness value is used as the ambient light value; a stabilization unit that generates stabilization control signals for the target control unit according to the ambient light value and ambient status information provided by the target control unit; and an exposure value control unit that computes a desired exposure value by comparing the target brightness value with the weighted mean brightness value and determines an exposure command according to the desired exposure value.
    Type: Grant
    Filed: June 21, 2016
    Date of Patent: January 16, 2018
    Assignees: Himax Imaging Limited, Himax Technologies Limited
    Inventors: Po-Chang Chen, Po-Fang Chen, Wei-Chieh Yang
  • Patent number: 9653513
    Abstract: A complementary metal-oxide-semiconductor (CMOS) image sensor includes an implant region of a second type formed in a crystalline layer of a first type. A channel of a transfer gate entirely covers the implant region, which partially joins a photodiode, a doped well and a floating diffusion node.
    Type: Grant
    Filed: April 8, 2016
    Date of Patent: May 16, 2017
    Assignee: Himax Imaging Limited
    Inventors: Yang Wu, Inna Patrick, Desmond Cheung, Kihong Kim, Feixia Yu