Patents by Inventor Takafumi Ishitsu

Takafumi Ishitsu 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: 8927939
    Abstract: The purpose of the present invention is to improve energy resolving power and prevent energy resolving power from deteriorating when a thick semiconductor detection element with a wide energy range is used, in a radiation measuring device using a semiconductor detector and a nuclear medicine diagnostic device. With the present invention, the purpose is achieved by pulsed wave value correction employing the difference of (Hs?Hf) between the pulsed wave height value Hs obtained from the slow speed shaping circuit, and the pulsed wave height value Hf obtained from the fast speed shaping circuit and normalized with respect to Hs. An even more desirable result may be obtained by employing either (Hs?Hf)/Hf or exp(k(Hs?Hf)/Hf), wherein k is a coefficient to be optimized, said optimization being dependent on the measurement assembly.
    Type: Grant
    Filed: February 3, 2011
    Date of Patent: January 6, 2015
    Assignee: Hitachi, Ltd.
    Inventors: Tomoyuki Seino, Yuichiro Ueno, Takafumi Ishitsu
  • Publication number: 20130270448
    Abstract: An image processing device of a radiation image acquisition device (100) uses a weighted filter to perform a smoothing (processing S102) on an image obtained by counting the number of incident gamma rays. The image processing device suppresses pixel values of a threshold value or less on the smoothed image (processing S103). Further, the image processing device again applies a weighted and smoothing filter to the image processed by a threshold-value processing, to expand the pixels of the accumulation portion (processing S104); thus providing an image that facilitates finding the accumulation portion of a radioisotope.
    Type: Application
    Filed: December 27, 2011
    Publication date: October 17, 2013
    Applicant: HITACHI, LTD.
    Inventors: Takafumi Ishitsu, Takatoshi Maruyama, Katsutoshi Tsuchiya, Yuichiro Ueno
  • Publication number: 20130146767
    Abstract: A radiation measuring device includes: a detector that detects radiation; a preamplifier that amplifies a signal outputted from the detector; a shaping amplifier that shapes the waveform of the signal outputted from the preamplifier; an A/D converter that converts the analog signal output from the shaping amplifier to a digital signal; and a digital data processing unit that calculates digital signal output from the A/D converter, wherein energy information of the radiation inputted to the detector is obtained from a pulse height of the pulse signal processed by the preamplifier and the shaping amplifier, and the pulse height of the current pulse is corrected in the digital data processing unit by performing an arithmetic operation using the pulse height information of the current pulse digitalized by the A/D converter, the generation time information of the preceding pulse, and the pulse height information of the preceding pulse.
    Type: Application
    Filed: August 4, 2011
    Publication date: June 13, 2013
    Applicant: HITACHI, LTD.
    Inventors: Tomoyuki Seino, Yuichiro Ueno, Takafumi Ishitsu
  • Patent number: 8357904
    Abstract: A radiation imaging apparatus comprises display means for displaying an image obtained by imaging an object and light projection means for projecting a light projection mark onto the object, and displays a light projection position on the object onto which the light projection mark is projected on the image. The light projection mark is projected as a line of intersection which is perpendicular to the surface of a detector and at which two planar flat light beams visually intersect each other, and the light projection position on the image is moved according to the movements of the flat light beams. By calculating projected lines obtained by projecting the light projection lines projected onto the object by the flat light beams onto the surface and displaying the projected lines on the image, the light projection position is displayed as a point of intersection of the projected lines on the image.
    Type: Grant
    Filed: February 18, 2009
    Date of Patent: January 22, 2013
    Assignee: Hitachi, Ltd.
    Inventors: Katsutoshi Tsuchiya, Takafumi Ishitsu, Tsuneaki Kawaguchi
  • Publication number: 20120326045
    Abstract: The purpose of the present invention is to improve energy resolving power and prevent energy resolving power from deteriorating when a thick semiconductor detection element with a wide energy range is used, in a radiation measuring device using a semiconductor detector and a nuclear medicine diagnostic device. With the present invention, the purpose is achieved by pulsed wave value correction employing the difference of (Hs?Hf) between the pulsed wave height value Hs obtained from the slow speed shaping circuit, and the pulsed wave height value Hf obtained from the fast speed shaping circuit and normalized with respect to Hs. An even more desirable result may be obtained by employing either (Hs?Hf)/Hf or exp(k(Hs?Hf)/Hf), wherein k is a coefficient to be optimized, said optimization being dependent on the measurement assembly.
    Type: Application
    Filed: February 3, 2011
    Publication date: December 27, 2012
    Applicant: HITACHI, LTD.
    Inventors: Tomoyuki Seino, Yuichiro Ueno, Takafumi Ishitsu
  • Patent number: 8338792
    Abstract: Provided between a bias power supply and a radiation detector are a noise filter and a bias voltage transmitting circuit. In a state where the bias voltage is applied, the noise filter circuit operates. In a state where the bias voltage is switched on and off, the bias voltage transmitting circuit and the noise filter circuit operate. In a state where the bias voltage is switched on and off, the bias voltage transmitting circuit operates.
    Type: Grant
    Filed: February 19, 2010
    Date of Patent: December 25, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Tomoyuki Seino, Yuichiro Ueno, Takafumi Ishitsu
  • Publication number: 20120232385
    Abstract: The radiation imaging device acquires incident position information of radiation for each detector by setting the size of a through-hole such that at least one pixel is arrayed in a plane view from a direction perpendicular to the detector plane; arranges a septa in displacing from a boundary line between a detector pair in a plane view from a direction perpendicular to the detector plane; further arranging the septa so as to be orthogonal to the boundary line between the detector pair in a plane view from a direction perpendicular to the detector plane; arranges the top of the through-hole in a plane view from a direction perpendicular to the detector plane, in displacing from the boundary line of the detector pair; and arranges the top of the detectors in a plane view from a direction perpendicular to the detector plane so as to be visible through the through-hole.
    Type: Application
    Filed: October 29, 2010
    Publication date: September 13, 2012
    Applicant: HITACHI, LTD.
    Inventors: Kaori Hattori, Atsuro Suzuki, Katsutoshi Tsuchiya, Takafumi Ishitsu, Keiji Kobashi
  • Patent number: 8253108
    Abstract: A radiation imaging system includes a detecting unit including a plurality of radiation detecting elements arranged in a plane for radiation detection, a collimator provided with through holes respectively aligned with the radiation detecting elements and opening in an entrance surface such that radiation from a specified direction is selectively made to fall on the radiation detecting elements. A second case joined to a first case fixed to the side surface of the collimator defines a holding chamber G, and a holder holding the detecting unit is placed in the holding chamber G such that spaces that allow the holder to be moved in a plane parallel to the entrance surface are formed between the holder and the second case. A position adjusting mechanism for adjusting the positional relation between the second case and the holder by moving the holder relative to the second case.
    Type: Grant
    Filed: December 23, 2008
    Date of Patent: August 28, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Katsutoshi Tsuchiya, Takafumi Ishitsu, Tsuneaki Kawaguchi
  • Patent number: 8148695
    Abstract: A PET apparatus comprises a plurality of detector units in the circumferential direction, wherein the detector unit includes a plurality of unit substrates therein, and wherein the unit substrate includes: a plurality of detectors upon which a ?-ray is incident; and an analog ASIC and digital ASIC for processing a ?-ray detection signal outputted by each of the detectors. The analog ASIC includes two slow systems having mutually different time constants, each of which outputs a pulseheight value. A noise determination part of the digital ASIC determines whether a relevant detection signal is an intended ?-ray detection signal or a noise based on a correlation between the pulseheight values, and a noise counting part counts the number of times of noise determination, and a detector output signal processing control part controls the signal processing with respect to an output signal from a relevant detector based on the count.
    Type: Grant
    Filed: May 13, 2011
    Date of Patent: April 3, 2012
    Assignee: Hitachi, Ltd.
    Inventors: Isao Takahashi, Takafumi Ishitsu, Yuichiro Ueno, Tomoyuki Seino
  • Publication number: 20110297837
    Abstract: The radiation detection module (20) is provided with a semiconductor element (1) having a plurality of pixels (Pn), radiation detection elements (30) in which a plurality of first electrodes (31n) are arranged along one side of the semiconductor element (1), and a second electrode (32m) is disposed astride a plurality of pixels (Pn) along the other side, and which output detection signals when a radioactive ray comes incident on the detection pixels (Pn), and a support PCB (21) placed to stand along the direction in which the radioactive ray comes incident. The support PCB (21) has a connection section (21a) detachably connectable to an external connecting section. Radiation detection elements (30) are connected on the support PCB (21) to fabricate a signal read-out circuit having mutually-perpendicular wiring in a pseudo way and that the incident position of the radioactive ray is identified by coincidence determination of the detection signals.
    Type: Application
    Filed: February 17, 2010
    Publication date: December 8, 2011
    Applicant: HITACHI, LTD.
    Inventors: Takafumi Ishitsu, Isao Takahashi, Katsutoshi Tsuchiya, Kazuma Yokoi, Yuichiro Ueno
  • Publication number: 20110215254
    Abstract: A PET apparatus comprises a plurality of detector units in the circumferential direction, wherein the detector unit includes a plurality of unit substrates therein, and wherein the unit substrate includes: a plurality of detectors upon which a ?-ray is incident; and an analog ASIC and digital ASIC for processing a ?-ray detection signal outputted by each of the detectors. The analog ASIC includes two slow systems having mutually different time constants, each of which outputs a pulseheight value. A noise determination part of the digital ASIC determines whether a relevant detection signal is an intended ?-ray detection signal or a noise based on a correlation between the pulseheight values, and a noise counting part counts the number of times of noise determination, and a detector output signal processing control part controls the signal processing with respect to an output signal from a relevant detector based on the count.
    Type: Application
    Filed: May 13, 2011
    Publication date: September 8, 2011
    Applicant: HITACHI, LTD.
    Inventors: Isao Takahashi, Takafumi Ishitsu, Yuichiro Ueno, Tomoyuki Seino
  • Publication number: 20110204248
    Abstract: Provided between a bias power supply and a radiation detector are a noise filter and a bias voltage transmitting circuit. In a state where the bias voltage is applied, the noise filter circuit operates. In a state where the bias voltage is switched on and off, the bias voltage transmitting circuit and the noise filter circuit operate. In a state where the bias voltage is switched on and off, the bias voltage transmitting circuit operates.
    Type: Application
    Filed: February 19, 2010
    Publication date: August 25, 2011
    Applicant: HITACHI, LTD.
    Inventors: Tomoyuki SEINO, Yuichiro UENO, Takafumi ISHITSU
  • Publication number: 20110164728
    Abstract: A radiation imaging apparatus comprises display means for displaying an image obtained by imaging an object and light projection means for projecting a light projection mark onto the object, and displays a light projection position on the object onto which the light projection mark is projected on the image. The light projection mark is projected as a line of intersection which is perpendicular to the surface of a detector and at which two planar flat light beams visually intersect each other, and the light projection position on the image is moved according to the movements of the flat light beams. By calculating projected lines obtained by projecting the light projection lines projected onto the object by the flat light beams onto the surface and displaying the projected lines on the image, the light projection position is displayed as a point of intersection of the projected lines on the image.
    Type: Application
    Filed: February 18, 2009
    Publication date: July 7, 2011
    Applicant: HITACHI, LTD.
    Inventors: Katsutoshi Tsuchiya, Takafumi Ishitsu, Tsuneaki Kawaguchi
  • Patent number: 7964849
    Abstract: A PET apparatus comprises a plurality of detector units in the circumferential direction, wherein the detector unit includes a plurality of unit substrates therein, and wherein the unit substrate includes: a plurality of detectors upon which a ?-ray is incident; and an analog ASIC and digital ASIC for processing a ?-ray detection signal outputted by each of the detectors. The analog ASIC includes two slow systems having mutually different time constants, each of which outputs a pulseheight value. A noise determination part of the digital ASIC determines whether a relevant detection signal is an intended ?-ray detection signal or a noise based on a correlation between the pulseheight values, and a noise counting part counts the number of times of noise determination, and a detector output signal processing control part controls the signal processing with respect to an output signal from a relevant detector based on the count.
    Type: Grant
    Filed: July 16, 2010
    Date of Patent: June 21, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Isao Takahashi, Takafumi Ishitsu, Yuichiro Ueno, Tomoyuki Seino
  • Patent number: 7952076
    Abstract: A radiation imaging system is configured by a collimator 30A including a detector 21 with a discrete detection pixel corresponding with a pixel and a plurality of radiation passages 31 and looks into a plurality of detectors 21 through one radiation passage 31 to set a step width of rotation around a rotation center axis X1 only for an angle ?p made by lines provided by connecting a center detector 21 of the radiation passage 31 and the adjacent two detectors 21. In the case of generating a flat plane projection image for one direction, radio-graphing is carried out on a projection image in a plurality of predetermined angle positions (??p, 0, +?p) in the circumferential direction of the rotation center axis X1 and thereby one plane projection image is obtained.
    Type: Grant
    Filed: April 15, 2009
    Date of Patent: May 31, 2011
    Assignees: Hitachi, Ltd., National University Corporation Hokkaido University
    Inventors: Katsutoshi Tsuchiya, Tsuneaki Kawaguchi, Yuichi Morimoto, Masatoshi Tanaka, Hiroshi Kitaguchi, Kazuma Yokoi, Takafumi Ishitsu, Naoki Kubo, Nagara Tamaki
  • Patent number: 7888648
    Abstract: A radiological measurement system protecting an amplifier from damage caused by a surge current, ensuring temporal continuity of measurement with a minimum dead time, and including a high voltage DC supply for applying a bias voltage to a radiation detector formed of semiconductor crystal, a controller for exercising on-off control on the bias voltage supplied from the high voltage DC supply, an amplifier, a protection circuit for protecting the amplifier from a surge current generated when the bias voltage is subjected to the on-off control, a control unit for preventing the surge current from flowing to the amplifier, and a switch provided in parallel with the protection circuit and controlled in operation state by the control unit, wherein the control unit controls the operation state of the switch in synchronism with the on-off control exercised by the control unit to prevent the surge current from flowing to the amplifier.
    Type: Grant
    Filed: February 18, 2009
    Date of Patent: February 15, 2011
    Assignee: Hitachi, Ltd.
    Inventors: Tomoyuki Seino, Takafumi Ishitsu, Yuichiro Ueno
  • Publication number: 20100308230
    Abstract: Provided are a detector array substrate and a nuclear medicine diagnosis device using the same. The detector array substrate is provided with a flat detection module stacked in plural detection elements, which is connected to said detectors each other, and have signal electrodes for reading out signals of respective detectors, and bias electrodes for applying bias voltage to respective detectors, in order to form plural detectors for detecting radiation; and stacked with the detectors by arranging the detection modules having the plural detectors, in an X direction, as well as by arranging the detection modules in a flat structure on both planes or one plane of a wiring board in a Z direction as for an XZ plane for detecting the radiation, and provided with the plural detection modules in a Y direction.
    Type: Application
    Filed: August 17, 2010
    Publication date: December 9, 2010
    Applicant: HITACHI, LTD.
    Inventors: Norihito YANAGITA, Tomoyuki SEINO, Takafumi ISHITSU, Tsutomu IMAI, Atsumi KAWATA, Shinya KOMINAMI
  • Publication number: 20100282974
    Abstract: A PET apparatus comprises a plurality of detector units in the circumferential direction, wherein the detector unit includes a plurality of unit substrates therein, and wherein the unit substrate includes: a plurality of detectors upon which a ?-ray is incident; and an analog ASIC and digital ASIC for processing a ?-ray detection signal outputted by each of the detectors. The analog ASIC includes two slow systems having mutually different time constants, each of which outputs a pulseheight value. A noise determination part of the digital ASIC determines whether a relevant detection signal is an intended ?-ray detection signal or a noise based on a correlation between the pulseheight values, and a noise counting part counts the number of times of noise determination, and a detector output signal processing control part controls the signal processing with respect to an output signal from a relevant detector based on the count.
    Type: Application
    Filed: July 16, 2010
    Publication date: November 11, 2010
    Applicant: HITACHI, LTD.
    Inventors: Isao Takahashi, Takafumi Ishitsu, Yuichiro Ueno, Tomoyuki Seino
  • Patent number: 7807974
    Abstract: A nuclear medical diagnosis apparatus capable of attaining improvement of the sensitivity by the reduction of a count loss of the data is provided. A data sort section inside a data acquisition unit re-arranges and outputs the data packet from a plurality of auxiliary data acquisition unit in order of the detection time data. A coincidence detection section includes a pair check section and a pair generation section. The pair check section refers to a context on the data packet re-arranged in order of the detection time, and judges a pair relating to a coincidence counting. The pair generation section, based on this judgment result, merges the data packet used as a pair, and outputs the same to the collection work station.
    Type: Grant
    Filed: February 20, 2008
    Date of Patent: October 5, 2010
    Assignee: Hitachi, Ltd.
    Inventors: Takafumi Ishitsu, Yuichiro Ueno, Kensuke Amemiya, Keiji Kobashi
  • Patent number: 7795590
    Abstract: A PET apparatus comprises a plurality of detector units in the circumferential direction, wherein the detector unit includes a plurality of unit substrates therein, and wherein the unit substrate includes: a plurality of detectors upon which a ?-ray is incident; and an analog ASIC and digital ASIC for processing a ?-ray detection signal outputted by each of the detectors. The analog ASIC includes two slow systems having mutually different time constants, each of which outputs a pulseheight value. A noise determination part of the digital ASIC determines whether a relevant detection signal is an intended ?-ray detection signal or a noise based on a correlation between the pulseheight values, and a noise counting part counts the number of times of noise determination, and a detector output signal processing control part controls the signal processing with respect to an output signal from a relevant detector based on the count.
    Type: Grant
    Filed: September 26, 2007
    Date of Patent: September 14, 2010
    Assignee: Hitachi, Ltd.
    Inventors: Isao Takahashi, Takafumi Ishitsu, Yuichiro Ueno, Tomoyuki Seino