Patents by Inventor Yasutaka Konno

Yasutaka Konno 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: 20200323502
    Abstract: X-ray photons are counted as to each of energy bands (bins) to which optimum energy ranges are provided, and an image with reduced noise is displayed in a short time. An energy range of at least one of multiple energy bands in an X-ray detector is adjusted, on the basis of a distribution of degrees of X-ray attenuation at respective energy levels, the distribution of degrees of X-ray attenuation being measured in advance with respect to a predetermined direction of a subject. By using the X-ray detector with the energy bands after the adjustment, photon-counting CT imaging is performed.
    Type: Application
    Filed: September 8, 2017
    Publication date: October 15, 2020
    Applicant: HITACHI, LTD.
    Inventors: Shinichi KOJIMA, Fumito WATANABE, Yasutaka KONNO, Isao TAKAHASHI, Kazuma YOKOI
  • Patent number: 10751020
    Abstract: There is disclosed an X-ray detector that includes a detection section, an addition rate determination section, an addition section, and a position information storage section in order to enhance the accuracy of interpolation of an output signal from a defective element and suppress artifacts with ease without increasing, for example, the length of processing time, the number of processing circuits, and the amount of interpolation data. The detection section includes a plurality of arrays of detection element groups that are each formed of a plurality of detection elements in correspondence with one pixel. The addition rate determination section determines addition rates for output signals of the detection elements. The addition section calculates the signal value of each pixel of a projection image by adding the output signals of the detection elements belonging to the detection element groups in accordance with the addition rates.
    Type: Grant
    Filed: February 3, 2017
    Date of Patent: August 25, 2020
    Assignee: Hitachi, Ltd.
    Inventor: Yasutaka Konno
  • Patent number: 10542947
    Abstract: The present invention is directed to make a photon-counting CT apparatus capable of more accurate data acquisition. Such apparatus is provided with a reference detection unit and a time measuring instrument to measure temporal fluctuations in a rotational direction of an X-ray irradiation unit. The apparatus corrects temporal fluctuations in the rotational direction involved in data measured by the reference detection unit, using time measurement data which is output by the time measuring instrument. Using corrected measurement data measured by the reference detection unit, the apparatus makes corrections of fluctuations pertaining to the X-ray tube of the X-ray irradiation unit and pile-up. Data corrections with high accuracy are thus enabled.
    Type: Grant
    Filed: November 17, 2016
    Date of Patent: January 28, 2020
    Assignee: Hitachi, Ltd.
    Inventors: Shinichi Kojima, Yasutaka Konno, Fumito Watanabe, Isao Takahashi
  • Patent number: 10383585
    Abstract: In an X-ray scanning apparatus including a photon counting type X-ray detection element, in order to perform counted number correction specialized for pile-up with high accuracy, the X-ray scanning apparatus includes an X-ray detector in which a plurality of photon counting type X-ray detection elements are disposed, each of the X-ray detection elements detecting an incident X-ray photon, classifying energy of the X-ray photon into two or more energy ranges, and counting the X-ray photon, and a correction unit that corrects the counted number in the X-ray detection element, in which the correction unit includes a counting error amount determination part that determines a counting error amount in a counted number due to pile-up according to a pile-up occurrence probability in two or more X-ray photons.
    Type: Grant
    Filed: August 25, 2015
    Date of Patent: August 20, 2019
    Assignee: HITACHI, LTD.
    Inventor: Yasutaka Konno
  • Patent number: 10302779
    Abstract: A flat pixel (20) is a single unit composing a radiation detector and is configured so as to be divided into at least four subpixels (21) such that even if a prescribed number of subpixels (21) are removed from each pixel (20) in order of largest effective area, the centroid (51) of the effective area of the entirety of the remaining subpixels (21) is positioned within a similar-shape region (30) having the same centroid (50) as the pixel (20) and having sides of lengths that are half those of the pixel (20).
    Type: Grant
    Filed: June 18, 2015
    Date of Patent: May 28, 2019
    Assignee: Hitachi, Ltd.
    Inventors: Isao Takahashi, Kazuma Yokoi, Eiji Moro, Yuichiro Ueno, Yasutaka Konno, Fumito Watanabe, Shinichi Kojima
  • Patent number: 10292668
    Abstract: In an X-ray scanning apparatus mounted with a photon counting type radiation detector, a data processing device of the X-ray scanning apparatus includes a correction unit that corrects a digital output value in each of the plurality of energy ranges with respect to each X-ray detection element in order to obtain an accurate projection image by correcting a counting error of the number of X-ray photons in each energy range. The correction unit includes an inflow amount calculation portion that calculates a digital amount corresponding to X-ray photons which flow from a certain X-ray detection element to another X-ray detection element, and an energy shift inflow amount/outflow amount calculation portion that calculates a digital amount corresponding to X-ray photons which flow into a high energy range due to energy shift in a single X-ray detection element, and performs correction by using the digital amounts calculated by the calculation portions.
    Type: Grant
    Filed: March 17, 2015
    Date of Patent: May 21, 2019
    Assignee: HITACHI, LTD.
    Inventor: Yasutaka Konno
  • Publication number: 20190029628
    Abstract: There is disclosed an X-ray detector that includes a detection section, an addition rate determination section, an addition section, and a position information storage section in order to enhance the accuracy of interpolation of an output signal from a defective element and suppress artifacts with ease without increasing, for example, the length of processing time, the number of processing circuits, and the amount of interpolation data. The detection section includes a plurality of arrays of detection element groups that are each formed of a plurality of detection elements in correspondence with one pixel. The addition rate determination section determines addition rates for output signals of the detection elements. The addition section calculates the signal value of each pixel of a projection image by adding the output signals of the detection elements belonging to the detection element groups in accordance with the addition rates.
    Type: Application
    Filed: February 3, 2017
    Publication date: January 31, 2019
    Applicant: Hitachi, Ltd.
    Inventor: Yasutaka KONNO
  • Publication number: 20190021685
    Abstract: The present invention is directed to make a photon-counting CT apparatus capable of more accurate data acquisition. Such apparatus is provided with a reference detection unit and a time measuring instrument to measure temporal fluctuations in a rotational direction of an X-ray irradiation unit. The apparatus corrects temporal fluctuations in the rotational direction involved in data measured by the reference detection unit, using time measurement data which is output by the time measuring instrument. Using corrected measurement data measured by the reference detection unit, the apparatus makes corrections of fluctuations pertaining to the X-ray tube of the X-ray irradiation unit and pile-up. Data corrections with high accuracy are thus enabled.
    Type: Application
    Filed: November 17, 2016
    Publication date: January 24, 2019
    Inventors: Shinichi KOJIMA, Yasutaka KONNO, Fumito WATANABE, Isao TAKAHASHI
  • Publication number: 20180263576
    Abstract: An X-ray CT data processing device is provided which when multi-energy photography is performed with an energy-separation type detector, and a subject is separated into a plurality of standard materials to create an image, estimates the appropriateness of posited standard materials, and in order to determine appropriate standard materials with satisfactory accuracy, processes CT data respectively acquired in a plurality of detection energy ranges to create a reconstructed image separated into predetermined standard materials.
    Type: Application
    Filed: October 18, 2016
    Publication date: September 20, 2018
    Applicant: Hitachi, Ltd.
    Inventor: Yasutaka KONNO
  • Patent number: 10022099
    Abstract: A change of X-ray radiation quality due to a material existing between an X-ray source and a detection element is estimated and corrected. Accordingly, deterioration of material discrimination ability in a dual energy imaging method can be prevented. An X-ray imaging apparatus is provided with an inherent filtration calculator configured to use measured data obtained by imaging air at two or more types of different tube voltages to calculate a deviation from a reference radiation quality, as a transmission length (inherent filtration) of a predetermined reference material. A reference-material transmission-length conversion is applied to the measured data according to the dual energy imaging method, thereby calculating the reference material transmission length (inherent filtration). When a subject is imaged, the dual energy imaging is performed by adding the inherent filtration calculated as to each detection element, and this produces an image with the change of radiation quality having been corrected.
    Type: Grant
    Filed: October 22, 2014
    Date of Patent: July 17, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Yushi Tsubota, Fumito Watanabe, Yasutaka Konno, Shinichi Kojima, Keisuke Yamakawa, Shinji Kurokawa
  • Patent number: 10010303
    Abstract: An image processing device or radiation imaging device for generating an image using output data from a detector for detecting a radiation transmitted through an object to be examined, wherein artifacts caused by a gap between an estimated output value and the true output value are reduced when estimating an output value of a defective element of the detector. Correction is performed not only for the output of the defective element but for the output of the surrounding normal elements used for the defective element correction by a blurring process. Additionally, whether or not to perform the blurring process for the surrounding normal elements and the degree of the blurring process are adjusted according to the device conditions, scanning conditions, and the like.
    Type: Grant
    Filed: March 11, 2014
    Date of Patent: July 3, 2018
    Assignee: HITACHI, LTD.
    Inventor: Yasutaka Konno
  • Patent number: 9977137
    Abstract: Provided is a technique in an X-ray imaging apparatus for implementing data interpolation approximating an ideal point response trajectory interpolation, along with reducing calculation load. A method is provided to perform interpolation at high speed, in a direction along the point response trajectory. Sinograms are interpolated in advance from measured data, as to representative angles (e.g., 0°, ±30°, ±60°, and 90°) only. When a pixel targeted for back projection is determined at the time of reconstruction, a slope of the point response trajectory is determined as to each view. According to the slope of the trajectory, each representative sinogram is added with weight, whereby interpolation data in association with any angle can be obtained.
    Type: Grant
    Filed: July 23, 2015
    Date of Patent: May 22, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Yushi Tsubota, Shinji Kurokawa, Keisuke Yamakawa, Yasutaka Konno, Shinichi Kojima, Fumito Watanabe
  • Patent number: 9924917
    Abstract: The present invention is capable of distinguishing four types or more of substances such as air, water (soft tissues), contrast medium, and bones (calcification) to diagnose progress of atherosclerotic sites using dual energy imaging. A subject is imaged with two types of different tube voltages and an image obtained by image reconstruction is binarized to carry out a reprojection process; thereby, the distance of penetration of air is estimated, the contribution of air in measurement projection data is determined, and the amount of reduction by the air is deducted from the projection data so as to enable distinction between four or more substances such as air, water (soft tissues), contrast medium, and bones (calcification).
    Type: Grant
    Filed: May 2, 2014
    Date of Patent: March 27, 2018
    Assignee: Hitachi, Ltd.
    Inventors: Yushi Tsubota, Fumito Watanabe, Yasutaka Konno, Shinichi Kojima, Keisuke Yamakawa
  • Publication number: 20170276808
    Abstract: A flat pixel (20) is a single unit composing a radiation detector and is configured so as to be divided into at least four subpixels (21) such that even if a prescribed number of subpixels (21) are removed from each pixel (20) in order of largest effective area, the centroid (51) of the effective area of the entirety of the remaining subpixels (21) is positioned within a similar-shape region (30) having the same centroid (50) as the pixel (20) and having sides of lengths that are half those of the pixel (20).
    Type: Application
    Filed: June 18, 2015
    Publication date: September 28, 2017
    Inventors: Isao TAKAHASHI, Kazuma YOKOI, Eiji MORO, Yuichiro UENO, Yasutaka KONNO, Fumito WATANABE, Shinichi KOJIMA
  • Publication number: 20170231584
    Abstract: In an X-ray scanning apparatus including a photon counting type X-ray detection element, in order to perform counted number correction specialized for pile-up with high accuracy, the X-ray scanning apparatus includes an X-ray detector in which a plurality of photon counting type X-ray detection elements are disposed, each of the X-ray detection elements detecting an incident X-ray photon, classifying energy of the X-ray photon into two or more energy ranges, and counting the X-ray photon, and a correction unit that corrects the counted number in the X-ray detection element, in which the correction unit includes a counting error amount determination part that determines a counting error amount in a counted number due to pile-up according to a pile-up occurrence probability in two or more X-ray photons
    Type: Application
    Filed: August 25, 2015
    Publication date: August 17, 2017
    Applicant: HITACHI, LTD.
    Inventor: Yasutaka KONNO
  • Publication number: 20170176609
    Abstract: Provided is a technique in an X-ray imaging apparatus for implementing data interpolation approximating an ideal point response trajectory interpolation, along with reducing calculation load. A method is provided to perform interpolation at high speed, in a direction along the point response trajectory. Sinograms are interpolated in advance from measured data, as to representative angles (e.g., 0°, ±30°, ±60°, and 90°) only. When a pixel targeted for back projection is determined at the time of reconstruction, a slope of the point response trajectory is determined as to each view. According to the slope of the trajectory, each representative sinogram is added with weight, whereby interpolation data in association with any angle can be obtained.
    Type: Application
    Filed: July 23, 2015
    Publication date: June 22, 2017
    Inventors: Yushi TSUBOTA, Shinji KUROKAWA, Keisuke YAMAKAWA, Yasutaka KONNO, Shinichi KOJIMA, Fumito WATANABE
  • Publication number: 20170105688
    Abstract: In an X-ray scanning apparatus mounted with a photon counting type radiation detector, a data processing device of the X-ray scanning apparatus includes a correction unit that corrects a digital output value in each of the plurality of energy ranges with respect to each X-ray detection element in order to obtain an accurate projection image by correcting a counting error of the number of X-ray photons in each energy range. The correction unit includes an inflow amount calculation portion that calculates a digital amount corresponding to X-ray photons which flow from a certain X-ray detection element to another X-ray detection element, and an energy shift inflow amount/out flow amount calculation portion that calculates a digital amount corresponding to X-ray photons which flow into a high energy range due to energy shift in a single X-ray detection element, and performs correction by using the digital amounts calculated by the calculation portions.
    Type: Application
    Filed: March 17, 2015
    Publication date: April 20, 2017
    Applicant: HITACHI, LTD.
    Inventor: Yasutaka KONNO
  • Patent number: 9552659
    Abstract: Difference of resolution depending on imaging position in one reconstructed image generated in the FFS method is reduced to improve measurement accuracy. The X-ray CT device interpolates missing data of the projection data obtained by the FFS method with view direction interpolation processing using real data of the projection data lining up along the angular direction of the rotational movement, and channel direction interpolation processing using real data of the projection data lining up along the channel direction, and generates a reconstructed image, in which contribution ratios of the projection data having been subjected to the view direction interpolation processing and the projection data having been subjected to the channel direction interpolation processing differ according to position of pixel in the reconstructed image.
    Type: Grant
    Filed: January 15, 2014
    Date of Patent: January 24, 2017
    Assignee: Hitachi, Ltd.
    Inventors: Shinichi Kojima, Keisuke Yamakawa, Fumito Watanabe, Yushi Tsubota, Yasutaka Konno
  • Patent number: 9482629
    Abstract: An X-ray CT apparatus includes: an X-ray generating unit configured to generate an X ray; an X-ray detecting unit including a plurality of X-ray detectors, each configured to detect the X ray generated from the X-ray generating unit and transmitted through an object; and an image generating unit configured to correct and reconstruct signals acquired by the X-ray detecting unit. While crosstalk correction of a plurality of the X-ray detectors is performed at the image generating unit, correction of a locally attenuating component is previously performed and correction of a whole component of the crosstalk is performed when the image is reconstructed.
    Type: Grant
    Filed: June 3, 2011
    Date of Patent: November 1, 2016
    Assignee: Hitachi, Ltd.
    Inventors: Shinichi Kojima, Fumito Watanabe, Hironori Ueki, Yasutaka Konno, Yushi Tsubota, Yukiko Ueki
  • Publication number: 20160199018
    Abstract: A change of X-ray radiation quality due to a material existing between an X-ray source and a detection element is estimated and corrected. Accordingly, deterioration of material discrimination ability in a dual energy imaging method can be prevented. An X-ray imaging apparatus is provided with an inherent filtration calculator configured to use measured data obtained by imaging air at two or more types of different tube voltages to calculate a deviation from a reference radiation quality, as a transmission length (inherent filtration) of a predetermined reference material. A reference-material transmission-length conversion is applied to the measured data according to the dual energy imaging method, thereby calculating the reference material transmission length (inherent filtration). When a subject is imaged, the dual energy imaging is performed by adding the inherent filtration calculated as to each detection element, and this produces an image with the change of radiation quality having been corrected.
    Type: Application
    Filed: October 22, 2014
    Publication date: July 14, 2016
    Inventors: Yushi TSUBOTA, Fumito WATANABE, Yasutaka KONNO, Shinichi KOJIMA, Keisuke YAMAKAWA, Shinji KUROKAWA