Patents by Inventor Douglas P. Hart

Douglas P. Hart 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).

  • Publication number: 20100039534
    Abstract: The attenuation and other optical properties of a medium are exploited to measure a thickness of the medium between a sensor and a target surface. Disclosed herein are various mediums, arrangements of hardware, and processing techniques that can be used to capture these thickness measurements and obtain three-dimensional images of the target surface in a variety of imaging contexts. This includes general techniques for imaging interior/concave surfaces as well as exterior/convex surfaces, as well as specific adaptations of these techniques to imaging ear canals, human dentition, and so forth.
    Type: Application
    Filed: July 24, 2009
    Publication date: February 18, 2010
    Inventors: Douglas P. Hart, Federico Frigerio, Davide M. Marini
  • Publication number: 20100042002
    Abstract: The attenuation and other optical properties of a medium are exploited to measure a thickness of the medium between a sensor and a target surface. Disclosed herein are various mediums, arrangements of hardware, and processing techniques that can be used to capture these thickness measurements and obtain three-dimensional images of the target surface in a variety of imaging contexts. This includes general techniques for imaging interior/concave surfaces as well as exterior/convex surfaces, as well as specific adaptations of these techniques to imaging ear canals, human dentition, and so forth.
    Type: Application
    Filed: July 24, 2009
    Publication date: February 18, 2010
    Inventors: Douglas P. Hart, Federico Frigerio, Davide M. Marini
  • Publication number: 20100027014
    Abstract: The attenuation and other optical properties of a medium are exploited to measure a thickness of the medium between a sensor and a target surface. Disclosed herein are various mediums, arrangements of hardware, and processing techniques that can be used to capture these thickness measurements and obtain three-dimensional images of the target surface in a variety of imaging contexts. This includes general techniques for imaging interior/concave surfaces as well as exterior/convex surfaces, as well as specific adaptations of these techniques to imaging ear canals, human dentition, and so forth.
    Type: Application
    Filed: July 24, 2009
    Publication date: February 4, 2010
    Inventors: Douglas P. Hart, Federico Frigerio, Davide M. Marini
  • Publication number: 20100020070
    Abstract: The attenuation and other optical properties of a medium are exploited to measure a thickness of the medium between a sensor and a target surface. Disclosed herein are various mediums, arrangements of hardware, and processing techniques that can be used to capture these thickness measurements and obtain three-dimensional images of the target surface in a variety of imaging contexts. This includes general techniques for imaging interior/concave surfaces as well as exterior/convex surfaces, as well as specific adaptations of these techniques to imaging ear canals, human dentition, and so forth.
    Type: Application
    Filed: July 24, 2009
    Publication date: January 28, 2010
    Inventors: Douglas P. Hart, Federico Frigerio, Davide M. Marini
  • Publication number: 20100022893
    Abstract: The attenuation and other optical properties of a medium are exploited to measure a thickness of the medium between a sensor and a target surface. Disclosed herein are various mediums, arrangements of hardware, and processing techniques that can be used to capture these thickness measurements and obtain three-dimensional images of the target surface in a variety of imaging contexts. This includes general techniques for imaging interior/concave surfaces as well as exterior/convex surfaces, as well as specific adaptations of these techniques to imaging ear canals, human dentition, and so forth.
    Type: Application
    Filed: July 24, 2009
    Publication date: January 28, 2010
    Inventor: Douglas P. Hart
  • Publication number: 20100019170
    Abstract: The attenuation and other optical properties of a medium are exploited to measure a thickness of the medium between a sensor and a target surface. Disclosed herein are various mediums, arrangements of hardware, and processing techniques that can be used to capture these thickness measurements and obtain three-dimensional images of the target surface in a variety of imaging contexts. This includes general techniques for imaging interior/concave surfaces as well as exterior/convex surfaces, as well as specific adaptations of these techniques to imaging ear canals, human dentition, and so forth.
    Type: Application
    Filed: July 24, 2009
    Publication date: January 28, 2010
    Inventors: Douglas P. Hart, Federico Frigerio, Davide M. Marini
  • Publication number: 20100007718
    Abstract: A three-dimensional imaging system uses a single primary optical lens along with various configurations of apertures, refocusing facilities, and the like to obtain three offset optical channels each of which can be separately captured with an optical sensor.
    Type: Application
    Filed: February 13, 2007
    Publication date: January 14, 2010
    Inventors: Janos Rohaly, JR., Douglas P. Hart
  • Patent number: 7646550
    Abstract: A three-dimensional imaging system uses a single primary optical lens along with three collinear apertures to obtain three offset optical channels each of which can be separately captured with an optical sensor.
    Type: Grant
    Filed: September 8, 2006
    Date of Patent: January 12, 2010
    Assignee: 3M Innovative Properties Company
    Inventors: Janos Rohaly, Douglas P. Hart, Thomas J. Brukilacchio
  • Publication number: 20090016642
    Abstract: A high-speed three-dimensional imaging system includes a single lens camera subsystem with an active imaging element and CCD element, and a correlation processing subsystem. The active imaging element can be a rotating aperture which allows adjustable non-equilateral spacing between defocused images to achieve greater depth of field and higher sub-pixel displacement accuracy. A speckle pattern is projected onto an object and images of the resulting pattern are acquired from multiple angles. The images are locally cross-correlated using a sparse array image correlation technique and the surface is resolved by using relative camera position information to calculate the three-dimensional coordinates of each locally correlated region. Increased resolution and accuracy are provided by recursively correlating the images down to the level of individual points of light and using the Gaussian nature of the projected speckle pattern to determine subpixel displacement between images.
    Type: Application
    Filed: August 7, 2008
    Publication date: January 15, 2009
    Applicant: Massachusetts Institute of Technology
    Inventor: Douglas P. Hart
  • Publication number: 20080204900
    Abstract: A three-dimensional imaging system uses a single primary optical lens along with three non-collinear apertures to obtain three offset optical channels each of which can be separately captured with an optical sensor.
    Type: Application
    Filed: May 8, 2008
    Publication date: August 28, 2008
    Inventors: Janos Rohaly, Douglas P. Hart, Thomas J. Brukilacchio
  • Publication number: 20080199829
    Abstract: The systems and methods disclosed herein provide real time display of three-dimensional dental data acquired intraorally from a dental patient.
    Type: Application
    Filed: September 3, 2006
    Publication date: August 21, 2008
    Inventors: Eric B. Paley, Janos Rohaly, Joseph Boerjes, Douglas P. Hart, Micah J. Rosenbloom, Steven V. Weeks
  • Patent number: 7372642
    Abstract: A three-dimensional imaging system uses a single primary optical lens along with three non-collinear apertures to obtain three offset optical channels each of which can be separately captured with an optical sensor.
    Type: Grant
    Filed: September 8, 2006
    Date of Patent: May 13, 2008
    Assignee: 3M Innovative Properties Company
    Inventors: Janos Rohaly, Douglas P. Hart, Thomas J. Brukilacchio
  • Patent number: 7284758
    Abstract: The present invention relates to seals having textured features. The present invention particularly relates to seals having contact surfaces with said features wherein the contact surface seals properly and is resistant to wear. The contact surface is able to perform in very severe environments, such as those found in earthmoving applications.
    Type: Grant
    Filed: July 17, 2000
    Date of Patent: October 23, 2007
    Assignee: Massachusetts Institute of Technology
    Inventors: Douglas P. Hart, Mary C. Boyce, Hugo M. Ayala, Oscar C. Yeh
  • Publication number: 20070188769
    Abstract: A three-dimensional imaging system uses a single primary optical lens along with three collinear apertures to obtain three offset optical channels each of which can be separately captured with an optical sensor.
    Type: Application
    Filed: September 8, 2006
    Publication date: August 16, 2007
    Inventors: Janos Rohaly, Douglas P. Hart, Thomas J. Brukilacchio
  • Publication number: 20070188601
    Abstract: A three-dimensional imaging system uses a single primary optical lens along with three non-collinear apertures to obtain three offset optical channels each of which can be separately captured with an optical sensor.
    Type: Application
    Filed: September 8, 2006
    Publication date: August 16, 2007
    Inventors: Janos Rohaly, Douglas P. Hart, Thomas J. Brukilacchio
  • Publication number: 20040155975
    Abstract: An active three-dimensional imaging system for optical apparatus includes a relay lens subsystem with an off-axis rotating aperture placed between an imaging or objective lens and an image recording device such as a CCD camera. According to another aspect, the imaging system can include an off-axis rotating aperture located between field and aperture diaphragms of an illumination subsystem. The rotating aperture allows adjustable non-equilateral spacing between images of out-of-focus object points to achieve higher spatial resolution, increased sensitivity and higher sub-pixel displacement accuracy than other systems.
    Type: Application
    Filed: September 17, 2003
    Publication date: August 12, 2004
    Inventors: Douglas P. Hart, Jan Lammerding, Janos Rohaly
  • Patent number: 6105968
    Abstract: A contact surface of a seal having textured features is described. The contact surface seals properly and is resistant to wear. The contact surface is able to perform in very severe environments, such as those found in earthmoving applications.
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: August 22, 2000
    Assignee: Massachusetts Institute of Technology
    Inventors: Oscar C. Yeh, Douglas P. Hart, Mary C. Boyce, Hugo A. Ayala
  • Patent number: 6108458
    Abstract: A method of image correlation includes providing one or more image arrays of pixel values wherein each pixel value is associated with one of a number of pixels. Pixel values in the image array which are beyond a pixel threshold value are selected and a correlation process is performed on the selected pixel values. The correlation process is preferably performed according to an error correlation function. The sparse array correlation process provides several orders of magnitude in increased processing speed over known correlation processing techniques and is useful for Particle Image Velocimetry analysis.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: August 22, 2000
    Assignee: Massachusetts Institute of Technology
    Inventor: Douglas P. Hart
  • Patent number: 5850485
    Abstract: A method of image correlation includes providing one or more image arrays of pixel values wherein each pixel value is associated with one of a number of pixels. Pixel values in the image array which are beyond a pixel threshold value are selected and a correlation process is performed on the selected pixel values. The correlation process is preferably performed according to an error correlation function. The sparse array correlation process provides several orders of magnitude in increased processing speed over known correlation processing techniques and is useful for Particle Image Velocimetry analysis.
    Type: Grant
    Filed: July 3, 1996
    Date of Patent: December 15, 1998
    Assignee: Massachusetts Institute of Technology
    Inventor: Douglas P. Hart