Patents by Inventor Bedabrata Pain

Bedabrata Pain 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: 6021172
    Abstract: An imaging device formed as a monolithic complementary metal oxide semiconductor Integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate, a readout circuit including at least an output field effect transistor formed in the substrate, and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node connected to the output transistor and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node and an analog-to-digital converter formed in the substrate connected to the output of the readout circuit.
    Type: Grant
    Filed: December 5, 1995
    Date of Patent: February 1, 2000
    Assignee: California Institute of Technology
    Inventors: Eric R. Fossum, Sunetra K. Mendis, Bedabrata Pain, Robert H. Nixon, Zhimin Zhou
  • Patent number: 5949483
    Abstract: An imaging device formed as a monolithic complementary metal oxide semiconductor integrated circuit in an industry standard complementary metal oxide semiconductor process, the integrated circuit including a focal plane array of pixel cells, each one of the cells including a photogate overlying the substrate for accumulating photo-generated charge in an underlying portion of the substrate and a charge coupled device section formed on the substrate adjacent the photogate having a sensing node and at least one charge coupled device stage for transferring charge from the underlying portion of the substrate to the sensing node. There is also a readout circuit, part of which can be disposed at the bottom of each column of cells and be common to all the cells in the column. The imaging device can also include an electronic shutter formed on the substrate adjacent the photogate, and/or a storage section to allow for simultaneous integration.
    Type: Grant
    Filed: January 22, 1997
    Date of Patent: September 7, 1999
    Assignee: California Institute of Technology
    Inventors: Eric R. Fossum, Sabrina E. Kemeny, Bedabrata Pain
  • Patent number: 5929800
    Abstract: An analog-to-digital converter for on-chip focal-plane image sensor applications. The analog-to-digital converter utilizes a single charge integrating amplifier in a charge balancing architecture to implement successive approximation analog-to-digital conversion. This design requires minimal chip area and has high speed and low power dissipation for operation in the 2-10 bit range. The invention is particularly well suited to CMOS on-chip applications requiring many analog-to-digital converters, such as column-parallel focal-plane architectures.
    Type: Grant
    Filed: August 5, 1997
    Date of Patent: July 27, 1999
    Assignee: California Institute of Technology
    Inventors: Zhimin Zhou, Bedabrata Pain
  • Patent number: 5909026
    Abstract: An image sensor operable to vary the output spatial resolution according to a received light level while maintaining a desired signal-to-noise ratio. Signals from neighboring pixels in a pixel patch with an adjustable size are added to increase both the image brightness and signal-to-noise ratio. One embodiment comprises a sensor array for receiving input signals, a frame memory array for temporarily storing a full frame, and an array of self-calibration column integrators for uniform column-parallel signal summation. The column integrators are capable of substantially canceling fixed pattern noise.
    Type: Grant
    Filed: June 3, 1997
    Date of Patent: June 1, 1999
    Assignee: California Institute of Technology
    Inventors: Zhimin Zhou, Eric R. Fossum, Bedabrata Pain
  • Patent number: 5886659
    Abstract: A current-mode analog-to-digital converter based on a current copier circuit with a constant bias current that is independent of the input signals. A second-order incremental .SIGMA.-.DELTA. conversion configuration is implemented. An array of such analog-to-digital converters can be integrated onto the focal plane of an imaging sensor array to achieve column-wise parallel analog-to-digital conversion.
    Type: Grant
    Filed: August 21, 1997
    Date of Patent: March 23, 1999
    Assignee: California Institute of Technology
    Inventors: Bedabrata Pain, Junichi Nakamura, Eric R. Fossum
  • Patent number: 5880691
    Abstract: A capacitively-coupled successive approximation analog-to-digital converter utilizes a capacitively coupled multiplying digital to analog converter to generate a succession of voltages which are compared to the input voltage to be digitized. The capacitively coupled multiplying digital to analog converter generates the required succession of analog voltage levels utilizing very low power in response to digital signals. A double-sided version of the invention processes differential inputs with improved common-non-ideality mode rejection.
    Type: Grant
    Filed: November 7, 1996
    Date of Patent: March 9, 1999
    Assignee: California Institute of Technology
    Inventors: Eric R. Fossum, Zhimin Zhou, Bedabrata Pain
  • Patent number: 5793322
    Abstract: An analog-to-digital converter for on-chip focal-plane image sensor applications. The analog-to-digital converter utilizes charge integrating amplifiers in a charge balancing architecture to implement successive approximation analog-to-digital conversion. This design requires minimal chip area and has high speed and low power dissipation for operation in the 2-10 bit range. The invention is particularly well suited to CMOS on-chip applications requiring many analog-to-digital converters, such as column-parallel focal-plane architectures.
    Type: Grant
    Filed: November 7, 1996
    Date of Patent: August 11, 1998
    Assignee: California Institute of Technology
    Inventors: Eric R. Fossum, Zhimin Zhou, Bedabrata Pain
  • Patent number: 5665959
    Abstract: A solid-state focal-plane imaging system comprises an N.times.N array of high gain, low-noise unit cells, each unit cell being connected to a different one of photovoltaic detector diodes, one for each unit cell, interspersed in the array for ultralow level image detection and a plurality of digital counters coupled to the outputs of the unit cell by a multiplexer (either a separate counter for each unit cell or a row of N of counters time shared with N rows of digital counters). Each unit cell includes two self-biasing cascode amplifiers in cascade for a high charge-to-voltage conversion gain (>1 mV/e.sup.-) and an electronic switch to reset input capacitance to a reference potential in order to be able to discriminate detection of an incident photon by the photoelectron (e.sup.-) generated in the detector diode at the input of the first cascode amplifier in order to count incident photons individually in a digital counter connected to the output of the second cascode amplifier.
    Type: Grant
    Filed: July 1, 1996
    Date of Patent: September 9, 1997
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Adminstration
    Inventors: Eric R. Fossum, Bedabrata Pain