Patents by Inventor Weize Xu

Weize Xu 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: 8253214
    Abstract: An image sensor includes a unit cell having a plurality of pixels; the unit cell comprising an amplifier input transistor that is shared by the plurality of pixels; a plurality of floating diffusions that are joined by a floating diffusion interconnect layer and are connected to the amplifier input transistor; and an interconnect layer which forms an output signal wire which shields the floating diffusion interconnect layer.
    Type: Grant
    Filed: May 25, 2006
    Date of Patent: August 28, 2012
    Assignee: Omnivision Technologies, Inc.
    Inventors: Robert M. Guidash, Ravi Mruthyunjaya, Weize Xu
  • Patent number: 7652706
    Abstract: An image sensor includes a photosensitive region that accumulates charge corresponding to received incident light; a transfer gate for transferring charge from the photosensitive region; a voltage supply having an increasing voltage over time; a floating diffusion for receiving the charge from the photosensitive region and converting the charge to a voltage; an amplifier for receiving and amplifying a signal from the floating diffusion; a comparator for comparing a voltage from the amplifier to a reference voltage; and a counter for counting clock cycles between initiation of the increasing voltage until a signal is received from the comparator indicating charge transfer from the photosensitive region to the floating diffusion; wherein a digital signal is generated that represents an unfilled capacity of the photosensitive region.
    Type: Grant
    Filed: February 15, 2006
    Date of Patent: January 26, 2010
    Assignee: Eastman Kodak Company
    Inventor: Weize Xu
  • Patent number: 7593050
    Abstract: An image sensor includes a plurality of pixels for capturing an image; a sample and hold circuit array having a plurality of units for receiving signals from the plurality of pixels representing the captured image; a decoder for selecting each of the units of the sample and hold circuit array for output; and a delay circuit that includes an adjustable time delay to the decoder for compensating for time delays.
    Type: Grant
    Filed: February 27, 2006
    Date of Patent: September 22, 2009
    Assignee: Eastman Kodak Company
    Inventor: Weize Xu
  • Patent number: 7465934
    Abstract: A CMOS image sensor includes a plurality of pixels arranged in an array; a plurality of sample and hold arrays; and a routing matrix which routes a signal from each pixel to one of the sample and hold arrays in a predetermined order.
    Type: Grant
    Filed: September 30, 2005
    Date of Patent: December 16, 2008
    Assignee: Eastman Kodak Company
    Inventor: Weize Xu
  • Publication number: 20080239105
    Abstract: A CMOS image sensor includes a photodiode for receiving incident light that is converted to a charge signal; a transfer mechanism for transferring the charge to a sensing node that converts the charge signal to an image voltage signal; and a sample-and-hold circuit. The sample-and-hold circuit includes a capacitor that receives the image voltage signal; and only one buffer amplifier that passes the image voltage signal to a differential amplifier. The buffer amplifier also receives a reset signal that is passed to the differential amplifier.
    Type: Application
    Filed: March 30, 2007
    Publication date: October 2, 2008
    Inventor: Weize Xu
  • Publication number: 20080204567
    Abstract: An active pixel image sensor comprising: (a) a pixel array having a plurality of pixels, each pixel comprising: (i) a photosensitive region connected to a charge-to-voltage conversion region; and (ii) an amplifier connected to the charge-to-voltage conversion region; and (b) a sample and hold circuit connected to one or more pixels comprising: (i) two capacitors for receiving and storing a reset signal and an image signal; (ii) two buffer amplifiers for respectively receiving the reset signal and the image signal respectively from the two capacitors; and (iii) a reference generator circuit connected to an input of the buffer amplifiers for removing offset of the buffer amplifier.
    Type: Application
    Filed: February 23, 2007
    Publication date: August 28, 2008
    Inventor: Weize Xu
  • Publication number: 20080169845
    Abstract: A CMOS image sensor includes a photosensitive region for collecting charge in response to incident light; a charge-to-voltage mechanism for receiving the charge from the photosensitive region and converting the charge to a voltage; an amplifier for receiving and amplifying the voltage; a sample and hold circuit includes (i) a first capacitor one for receiving the voltage and a second capacitor for receiving a reset level; a first bus for receiving the voltage from the first capacitor and a second bus for receiving the reset level from the second capacitor; a differential difference amplifier for receiving the image voltage and the reset level and for determining a difference level between the image voltage and the reset level and for removing offset of the amplifier; and first and second switches respectively connected to the first and second bus for providing an electrical path for removing charge from each bus.
    Type: Application
    Filed: January 12, 2007
    Publication date: July 17, 2008
    Inventor: Weize Xu
  • Patent number: 7385636
    Abstract: An image sensor includes a plurality of pixels for capturing incident light that is converted to a signal representing an image; wherein noise is combined with a signal representing both the image and a reset level; a plurality of dark reference pixels that generate noise that substantially correspond or equally correspond to the noise in the image and reset level; and a sample and hold circuit that reads out the image signal and cancels or substantially cancels out the noise from the image signal and reset level by canceling the noise from image and reset level with the noise generated from the dark reference pixels.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: June 10, 2008
    Assignee: Eastman Kodak Company
    Inventor: Weize Xu
  • Patent number: 7382008
    Abstract: An image sensor includes a photosensitive region that accumulates charge corresponding to received incident light; a transfer gate for transferring all or a portion of the charge from the photosensitive region; a voltage supply having an increasing voltage over time that is applied to the transfer gate; a floating diffusion for receiving the all or a portion of the charge from the photosensitive region and converting the charge to a voltage; an amplifier for receiving and amplifying a signal from the floating diffusion; a pulse detector for detecting a voltage pulse from the amplifier; and a counter for counting clock cycles between initiation of the increasing voltage until a signal is received from the detector which indicates initiation of charge transfer from the photosensitive region to the floating diffusion.
    Type: Grant
    Filed: May 2, 2006
    Date of Patent: June 3, 2008
    Assignee: Eastman Kodak Company
    Inventor: Weize Xu
  • Publication number: 20070257284
    Abstract: An image sensor includes a photosensitive region that accumulates charge corresponding to received incident light; a transfer gate for transferring all or a portion of the charge from the photosensitive region; a voltage supply having an increasing voltage over time that is applied to the transfer gate; a floating diffusion for receiving the all or a portion of the charge from the photosensitive region and converting the charge to a voltage; an amplifier for receiving and amplifying a signal from the floating diffusion; a pulse detector for detecting a voltage pulse from the amplifier; and a counter for counting clock cycles between initiation of the increasing voltage until a signal is received from the detector which indicates initiation of charge transfer from the photosensitive region to the floating diffusion.
    Type: Application
    Filed: May 2, 2006
    Publication date: November 8, 2007
    Inventor: Weize Xu
  • Publication number: 20070200942
    Abstract: An image sensor includes a plurality of pixels for capturing an image; a sample and hold circuit array having a plurality of units for receiving signals from the plurality of pixels representing the captured image; a decoder for selecting each of the units of the sample and hold circuit array for output; and a delay circuit that includes an adjustable time delay to the decoder for compensating for time delays.
    Type: Application
    Filed: February 27, 2006
    Publication date: August 30, 2007
    Inventor: Weize Xu
  • Publication number: 20070188640
    Abstract: An image sensor includes a photosensitive region that accumulates charge corresponding to received incident light; a transfer gate for transferring charge from the photosensitive region; a voltage supply having an increasing voltage over time; a floating diffusion for receiving the charge from the photosensitive region and converting the charge to a voltage; an amplifier for receiving and amplifying a signal from the floating diffusion; a comparator for comparing a voltage from the amplifier to a reference voltage; and a counter for counting clock cycles between initiation of the increasing voltage until a signal is received from the comparator indicating charge transfer from the photosensitive region to the floating diffusion; wherein a digital signal is generated that represents an unfilled capacity of the photosensitive region.
    Type: Application
    Filed: February 15, 2006
    Publication date: August 16, 2007
    Inventor: Weize Xu
  • Patent number: 7238926
    Abstract: A method of making an image sensor, the method includes the steps of providing a plurality of pixels each with a photodetector; providing an amplifier that is shared between the plurality of photodetectors; providing a transfer gate associated with each photodetector; providing a charge-to-voltage conversion region that is shared between the plurality of photodetectors; determining a capacitance between each transfer gate and the charge-to-voltage conversion region; and modifying the capacitance to be substantially the same by altering a physical structure within one or more pixels.
    Type: Grant
    Filed: April 5, 2006
    Date of Patent: July 3, 2007
    Assignee: Eastman Kodak Company
    Inventors: R. Michael Guidash, Ravi Mruthyunjaya, Weize Xu
  • Publication number: 20070075255
    Abstract: A CMOS image sensor includes a plurality of pixels arranged in an array; a plurality of sample and hold arrays; and a routing matrix which routes a signal from each pixel to one of the sample and hold arrays in a predetermined order.
    Type: Application
    Filed: September 30, 2005
    Publication date: April 5, 2007
    Inventor: Weize Xu
  • Publication number: 20060273353
    Abstract: An image sensor includes a unit cell having a plurality of pixels; the unit cell comprising an amplifier input transistor that is shared by the plurality of pixels; a plurality of floating diffusions that are joined by a floating diffusion interconnect layer and are connected to the amplifier input transistor; and an interconnect layer which forms an output signal wire which shields the floating diffusion interconnect layer.
    Type: Application
    Filed: May 25, 2006
    Publication date: December 7, 2006
    Inventors: Robert Guidash, Ravi Mruthyunjaya, Weize Xu
  • Publication number: 20060273240
    Abstract: A method of making an image sensor, the method includes the steps of providing a plurality of pixels each with a photodetector; providing an amplifier that is shared between the plurality of photodetectors; providing a transfer gate associated with each photodetector; providing a charge-to-voltage conversion region that is shared between the plurality of photodetectors; determining a capacitance between each transfer gate and the charge-to-voltage conversion region; and modifying the capacitance to be substantially the same by altering a physical structure within one or more pixels.
    Type: Application
    Filed: April 5, 2006
    Publication date: December 7, 2006
    Inventors: R. Guidash, Ravi Mruthyunjaya, Weize Xu
  • Publication number: 20060209200
    Abstract: An image sensor includes a plurality of photo-sensitive elements arranged in an array in which each photo-sensitive element converts incident light into a charge packet; a charge-to-voltage converter that receives each charge packet and converts the charge packet into a voltage; a voltage-to-frequency converter that receives each voltage and converts the voltage into a signal having a frequency; and a frequency-to-digital signal converter that receives each signal having the frequency and converts the signal having the frequency into a digital signal.
    Type: Application
    Filed: March 15, 2005
    Publication date: September 21, 2006
    Inventor: Weize Xu
  • Publication number: 20060203114
    Abstract: A CMOS image sensor includes a plurality of pixels defining an imaging area each pixel includes a photosensitive area that converts incident light into a charge; a first transistor having a transfer gate that transfers charge from the photosensitive area to a charge-to-voltage region; a second transistor that resets the voltage of the charge-to-voltage region; a third transistor that amplifies voltage from the charge-to-voltage region; and a select mechanism positioned outside the imaging area on the image sensor that selects a predefined number of pixels for readout from the third transistor.
    Type: Application
    Filed: March 8, 2005
    Publication date: September 14, 2006
    Inventor: Weize Xu
  • Publication number: 20050243194
    Abstract: An image sensor includes a plurality of pixels for capturing incident light that is converted to a signal representing an image; wherein noise is combined with a signal representing both the image and a reset level; a plurality of dark reference pixels that generate noise that substantially correspond or equally correspond to the noise in the image and reset level; and a sample and hold circuit that reads out the image signal and cancels or substantially cancels out the noise from the image signal and reset level by canceling the noise from image and reset level with the noise generated from the dark reference pixels.
    Type: Application
    Filed: April 30, 2004
    Publication date: November 3, 2005
    Inventor: Weize Xu
  • Publication number: 20050094005
    Abstract: A method for outputting signals from dark reference pixels, the method includes the steps of transferring signals from dark reference pixels that are shielded from light to a plurality of storage circuit elements; and transferring signals substantially simultaneously from each of the plurality of storage circuit elements to an operational amplifier on one clock cycle which operational amplifier averages all the signals from the sample and hold circuits for providing an approximate average dark reference signal.
    Type: Application
    Filed: November 3, 2003
    Publication date: May 5, 2005
    Inventor: Weize Xu