Patents by Inventor Keiji Umetani
Keiji Umetani 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).
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Patent number: 5960058Abstract: The method for generating an X-ray image of the present invention by correcting a measured fluorographic image or radiographic image and removing the veiling glare component and scattered X-ray component has (1) a step of generating a veiling glare component image and a scattered X-ray component image corresponding to the fluorographic image or radiographic image from the measured fluorographic image or radiographic image independently and (2) a step of obtaining the difference between the measured fluorographic image or radiographic image and the veiling glare component image and scattered X-ray component image and executes a correction of removing the veiling glare component and scattered X-ray component from the measured fluorographic image or radiographic image.Type: GrantFiled: November 29, 1996Date of Patent: September 28, 1999Assignee: Hitachi Medical CorporationInventors: Rika Baba, Ken Ueda, Hironori Ueki, Keiji Umetani
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Patent number: 5880470Abstract: A 2-dimensional radiation image detector wherein a plurality of conversion elements for converting a radiation into visible light and a plurality of photo-sensitive elements for detecting the visible light and accumulating signals are formed an elements board includes two elements boards arranged in an overlapping relationship with each other and each having the plurality of photo-sensitive elements arranged two-dimensionally thereon such that the distance between centers of the photo-sensitive elements in one direction of the arrangement is substantially equal to a width of the photo-sensitive elements while the distance between the centers of the photo-sensitive elements in a direction perpendicular to the one direction is substantially equal to twice the width of the photo-sensitive elements and such that that portion of a radiation directed upon the two overlapping elements boards which has passed through a first one of the elements boards other than locations of the photo-sensitive elements is detected bType: GrantFiled: May 6, 1996Date of Patent: March 9, 1999Assignees: Hitachi, Ltd., Hitachi Medical CorporationInventors: Keiji Umetani, Ken Ueda, Tetsurou Minemura, Kazutaka Tsuji, Koichi Koike
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Patent number: 5818064Abstract: A method and apparatus is provided for picking up and displaying a stereoscopic image from an object permeated with radioactive rays. A plurality of radioactive rays which are non-parallel with each other are directed substantially simultaneously onto an object to generate a plurality of superimposed images of the object. The superimposed images of the object are divided into a plurality of discrete partial images formed on a pickup surface, so that each point of the object will be included in a plurality of the partial images, with the partial images showing the same point being spatially separated from one another on the pickup surface. A stereoscopic image of the object is then reconstructed by processing the partial images so that partial images generated by each of the sources of the radioactive rays will be respectively used to generate separate images of the object to form the stereoscopic image of the object.Type: GrantFiled: June 7, 1996Date of Patent: October 6, 1998Assignee: Hitachi, Ltd.Inventors: Akihiko Kohgami, Tadaaki Hirai, Keiji Umetani
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Patent number: 5600701Abstract: In order to image an object larger than a field of view for observation, imaging is effected by dividing it into several times and pictures thus imaged are synthesized to constitute a whole image. In order to image several times, only a detecting unit is moved and an X-ray source is substantially fixed with respect to the object. Images thus obtained include a common part of the object and are joined so that the common part are overlapped on each other. In case where an image pick-up tube is included in the detecting unit, the image pick-up tube is made operable, after a period of time necessary for attenuation of microphonic noise has lapsed, measured from a point of time where the detecting unit has been stopped.Type: GrantFiled: May 10, 1994Date of Patent: February 4, 1997Assignee: Hitachi Medical CorporationInventors: Rika Baba, Ken Ueda, Yoichi Onodera, Keiji Umetani, Hisatake Yokouchi, Shigekazu Hara, Tomoharu Kajiyama, Fumitaka Takahashi
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Patent number: 5598453Abstract: An X-ray apparatus for collecting X-ray transmission data of a subject from a plurality of directions to generate an X-ray transmission image or X-ray CT image of the subject, which includes an X-ray generator for generating an X-ray, an X-ray detector for detecting a transmission X-ray after the X-ray generated by the X-ray generator is transmitted through the subject, a rotation unit for rotating an imaging unit including the X-ray generator and the X-ray detector around the subject, a data collector for converting an output signal of the X-ray detector to a digital signal and collecting the digital signal, a signal processor for subjecting data collected by the data collector to a signal processing operation, a display for displaying thereon as an image the data collected by the data collector and the data subjected by the signal processor to the signal processing operation, and a position change unit for moving a relative position of a rotation center of the imaging unit and the subject in a direction parType: GrantFiled: August 22, 1995Date of Patent: January 28, 1997Assignee: Hitachi Medical CorporationInventors: Rika Baba, Ken Ueda, Kensuke Sekihara, Hironori Ueki, Keiji Umetani
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Patent number: 5583345Abstract: A method and apparatus is provided for picking up and displaying a stereoscopic image from an object permeated with radioactive rays. In accordance with the method, a plurality of radioactive rays which are non-parallel with each other are directed substantially simultaneously onto an object to generate a plurality of superimposed images of the object. The superimposed images of the object are divided into a plurality of discrete partial images formed on a pickup surface, so that each point of the object will be included in a plurality of the partial images, with the partial images showing the same point being spatially separated from one another on the pickup surface, A stereoscopic image of the object is then reconstructed by processing the partial images so that partial images generated by each of the sources of the radioactive rays will be respectively used to generate separate images of the object to form the stereoscopic image of the object.Type: GrantFiled: September 7, 1994Date of Patent: December 10, 1996Assignee: Hitachi, Ltd.Inventors: Akihiko Kohgami, Tadaaki Hirai, Keiji Umetani
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Patent number: 5528655Abstract: A radiologic three-dimensional imaging apparatus comprises a device for generating an X-ray, a two-dimensional X-ray image detector including an avalanche multiplication image pickup tube for detecting an image of an object with the X-ray transmitted therethrough, a device for producing an average intensity distribution from a plurality of intensity distributions of the X-ray transmitted image, and a device for setting the target voltage applied to the photoconductive layer of the avalanche multiplication image pickup tube for each electron beam scanning position in such a manner the target voltage is high at the central portion of the visual field of the object and low at the peripheral portion thereof.Type: GrantFiled: February 23, 1994Date of Patent: June 18, 1996Assignee: Hitachi, Ltd.Inventors: Keiji Umetani, Ken Ueda, Hisatake Yokouchi
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Patent number: 5526442Abstract: An X-ray radiography method and apparatus in which a phantom such as a chart having elements arranged in predetermined positions is irradiated with X-rays and an X-rays detection unit detects signals thereof. An image of the chart is obtained and a center position of each of the elements in the image of the chart is obtained as well as for those elements which are not within the imaging field of view. Pixel positions for a distortion free image is obtained and a transform table is prepared making each of the pixel positions in the image of the chart correspond to each of the pixel positions in the distortion free image. A plurality of digital images of a subject to be examined are obtained and the digital images are corrected in accordance with the transform table. The corrected digital images are then joined together and a digital image is displayed, wherein common portions in the corrected images are in accordance with each other.Type: GrantFiled: October 4, 1994Date of Patent: June 11, 1996Assignee: Hitachi Medical CorporationInventors: Rika Baba, Ken Ueda, Hisatake Yokouchi, Keiji Umetani, Yoichi Onodera
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Patent number: 5485500Abstract: A digital X-ray imaging system having an X-ray generator, an X-ray generator controller for controlling the X-ray generator, an X-ray detecting unit for detecting an X-ray transmitted through a subject, the X-ray detecting unit having an X-ray grid for shielding a scattered X-ray, a signal processor for acquiring a signal from the X-ray detecting unit and processing the signal to obtain a digital X-ray image of the subject, and a display device for displaying an image of the subject obtained by the signal processor. The system is provided with a position changing unit for changing a relative position between the X-ray detecting unit and the subject, a position change controller for controlling the position changing unit, and an imaging-sequence controller for controlling the position change controller and the X-ray generator controller.Type: GrantFiled: January 26, 1994Date of Patent: January 16, 1996Assignee: Hitachi Medical CorporationInventors: Rika Baba, Ken Ueda, Hisatake Yokouchi, Yoichi Onodera, Keiji Umetani, Masayuki Tsuneoka
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Patent number: 5402463Abstract: An X-ray imaging apparatus is constructed with a combination of an X-ray image intensifier, a relay optical system, and a video camera with avalanche multiplication camera tube. The video camera is controlled by an image acquisition circuit, a synchronizing signal generation circuit, and an applying voltage control circuit. The applying voltage control circuit for controlling the voltage to be applied to the video camera with avalanche multiplication camera tube controls the applying voltage on the basis of image data in an image memory so that the gray scale level of a detected visible image is corrected.Type: GrantFiled: August 19, 1993Date of Patent: March 28, 1995Assignee: Hitachi Medical CorporationInventors: Keiji Umetani, Ken Ueda, Yoichi Onodera, Hisatake Yokouchi
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Patent number: 5353325Abstract: An X-ray fluorograph and radiograph apparatus including an X-ray television camera having an avalanche multiplication operation type image pick-up tube having an input/output characteristic in which increment of an output reduces gradually against increase of dose of incident X-rays and a unit for setting X-ray latitude and a multiplication factor of an image pick-up tube to optimum values for inputted radiograph conditions by controlling a voltage value applied to the image pick-up tube and a value of a stop of an optical system, and making it possible to obtain X-ray latitude at 1,000 or more.Type: GrantFiled: November 30, 1992Date of Patent: October 4, 1994Assignee: Hitachi Medical CorporationInventors: Ken Ueda, Hisatake Yokouchi, Keiji Umetani, Yoichi Onodera
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Patent number: 4945552Abstract: An energy subtraction image measuring system for selectively depicting any target element using X-rays includes an X-ray filter containing the target element. It measures an X-ray image by using a quasi-monoenergetic X-ray beam obtained without using the filter and having a photon energy range that extends above and below the absorption edge of the target element, as well as an X-ray image using an X-ray beam containing only the photon energy component having photon energy levels lower than the absorption edge which is obtained by using the filter. The energy subtraction image measuring system then generates an energy substraction image by the operation of the thus obtained data.Type: GrantFiled: November 30, 1988Date of Patent: July 31, 1990Assignee: Hitachi, Ltd.Inventors: Ken Ueda, Keiji Umetani, Yoshio Suzuki
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Patent number: 4890310Abstract: An x-ray having the energy bandwidth which extends between above and below the absorption edge energy of an element constituting a contrast agent is emitted from an x-ray source as an x-ray to be projected to an object, the x-ray at the higher energy component than the absorption energy of the contrast-agent constituting element is detected by one x-ray detector, the x-ray, having been transmitted through the one x-ray detector, at the lower energy component than the absorption edge energy of the contrast agent constituting element is detected by another x-ray detector, and a subtraction image is obtained by processing the image data from both detectors.Type: GrantFiled: October 9, 1987Date of Patent: December 26, 1989Assignee: Hitachi, Ltd.Inventors: Keiji Umetani, Ken Ueda, Ryuichi Suzuki, Hisatake Yokouchi
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Patent number: 4598203Abstract: A multielement radiation detector in which many elements are arranged in array. Each element includes a scintillator which is tilted with respect to the incident direction of radiant rays, and a silicon photodiode which is opposed to the plane of incidence of the scintillator. The light-receiving plane of the silicon photodiode is tilted to meet the inclination of the scintillator. Therefore, the gradient of detection sensitivity distribution is reduced in the thickness direction of the detectors.Type: GrantFiled: October 23, 1984Date of Patent: July 1, 1986Assignees: Hitachi, Ltd., Hitachi Medical CorporationInventors: Keiji Umetani, Atsushi Suzuki, Manabu Nakagawa, Minoru Yoshida, Fumio Kawaguchi, Hiromichi Yamada, Kouichi Koike