Patents by Inventor Atsushi Iwashita

Atsushi Iwashita 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: 9541653
    Abstract: A radiation imaging apparatus includes a pixel array in which a plurality of pixels which detects radiation are arrayed to form a plurality of rows and a plurality of columns, a detection circuit which detects information having correlation to a radiation dose to the pixel array and output a detection signal corresponding to the information, and a control unit which detects radiation irradiation to the pixel array based on a plurality of integrated values obtained by integrating one of the detection signal and a result of processing applied to the detection signal in a plurality of integral intervals and control the pixel array in accordance with the detection.
    Type: Grant
    Filed: February 25, 2014
    Date of Patent: January 10, 2017
    Assignee: Canon Kabushiki Kaisha
    Inventors: Atsushi Iwashita, Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Hideyuki Okada, Sho Sato, Eriko Sato, Takuya Ryu
  • Publication number: 20160370225
    Abstract: A radiation imaging apparatus includes a pixel array having a plurality of pixels configured to detect radiation, a detector configured to detect radiation irradiation, and a controller. In a case in which a measured value obtained by using the detector exceeds a threshold in one range out of a positive range and a negative range with respect to a reference value, the controller controls a radiation image capturing operation by determining that the radiation irradiation has started. The controller changes the threshold in accordance with the measured value of the other range out of the positive range and the negative range.
    Type: Application
    Filed: June 15, 2016
    Publication date: December 22, 2016
    Inventors: Atsushi IWASHITA, Toshio KAMESHIMA, Hideyuki OKADA, Eriko SATO
  • Patent number: 9468414
    Abstract: An imaging system comprises: a plurality of pixels each for converting light, converted from radiation by a conversion unit, into an electrical signal; an extracting unit that extracts, based on an image formed based on output signals from the pixels, a pixel with noise generated by the radiation that has transmitted through the conversion unit to arrive at the pixels; and a correcting unit that performs correction to remove the noise with respect to an output signal from the extracted pixel, wherein the extracting unit extracts the pixel with the noise by performing division between first and second images, the first image being formed based on the output signals from the pixels in accordance with the radiation to the conversion unit during a first period, the second image being formed based on these output signals in accordance with that radiation during a second period after the first period.
    Type: Grant
    Filed: March 14, 2014
    Date of Patent: October 18, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takuya Ryu, Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Sho Sato, Atsushi Iwashita, Eriko Sato, Hideyuki Okada
  • Patent number: 9470800
    Abstract: A radiation imaging apparatus includes a pixel array having pixels including conversion elements and switching elements, a bias line for supplying a bias potential to the conversion elements; driving lines for supplying a signal to control the switching elements, a driving unit for performing an initialization operation of supplying a driving signal to each driving line group, switching each driving signal from an OFF voltage to an ON voltage, and then returning the driving signal to the OFF voltage; an acquisition unit configured to acquire a plurality of times in each driving cycle a signal value representing a current flowing through the bias line; a calculation unit configured to calculate radiation information based on the signal values; and a determination unit configured to determine whether irradiation of the pixel array with radiation is present based on the radiation information.
    Type: Grant
    Filed: February 25, 2014
    Date of Patent: October 18, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventors: Atsushi Iwashita, Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Hideyuki Okada, Sho Sato, Eriko Sato, Takuya Ryu
  • Patent number: 9470802
    Abstract: A radiographic image capturing apparatus, comprising a plurality of sensors arrayed on a substrate, a driving unit, a detection unit and a control unit, wherein the control unit is configured to perform a first control controlling the driving unit so as to repeatedly initialize the plurality of sensors on a row-by-row basis before a start of emission of radiation, and a second control controlling the driving unit so as to interrupt the initialization in response to a detection signal from the detection unit and cause the plurality of sensors to output signals, and the apparatus further comprises a determination unit configured to determine whether or not the detection signal is a signal which was output in response to the start of emission of radiation.
    Type: Grant
    Filed: May 18, 2015
    Date of Patent: October 18, 2016
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Hideyuki Okada, Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Atsushi Iwashita, Eriko Sato, Takuya Ryu, Kosuke Terui
  • Patent number: 9462989
    Abstract: An imaging apparatus has an AEC function that can prevent irregularities in photographed images, without being increased in size. The imaging apparatus comprises a plurality of pixels arranged in a matrix shape, each of the plurality of pixels including a conversion element for converting radiation or light into an electric charge, a plurality of lines that are connected to the plurality of pixel units and that extend in different directions to each other, a current monitor circuit that monitors currents flowing in the plurality of lines, and an arithmetic unit that calculates a two-dimensional distribution by performing back-projection processing with respect to the currents flowing in the plurality of lines monitored by the current monitor circuit.
    Type: Grant
    Filed: December 23, 2013
    Date of Patent: October 11, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsuro Takenaka, Toshio Kameshima, Tomoyuki Yagi, Sho Sato, Atsushi Iwashita, Eriko Sato, Hideyuki Okada, Takuya Ryu
  • Publication number: 20160291170
    Abstract: A radiographic image capturing apparatus includes: a pixel array in which a plurality of pixels outputting an electrical signal corresponding to radiation are arranged; a readout circuit section; and a member for preventing radiation from entering the readout circuit section. The pixel array includes a first region in which some pixels used for generating image signals are arranged, and a second region in which other pixels not used for generating the image signals are arranged in at least part of a region around the first region. From an outer side toward an inner side of the pixel array, an end on the inner side of the readout circuit section disposed in the second region, an end on the inner side of an orthogonal projection of the member to the pixel array, and an end on the inner side of the second region are arranged in this order.
    Type: Application
    Filed: October 30, 2014
    Publication date: October 6, 2016
    Inventors: Katsuro Takenaka, Toshio Kameshima, Tomoyuki Yagi, Atsushi Iwashita, Eriko Sato, Hideyuki Okada, Takuya Ryu, Kosuke Terui, Takashi Takasaki
  • Publication number: 20160270755
    Abstract: A radiation imaging apparatus is provided. The apparatus comprises a plurality of pixels and a signal processing unit configured to read out an analog signal from each pixel and output an image signal. The signal processing unit comprises a conversion unit configured to convert the analog signal into a digital signal using an A/D converter such that the digital signals of a first group pixels include a first offset components and the digital signals of a second group pixels include a second offset components, and a digital signal processing unit. The digital signal processing unit calculates a correction value using the digital signals of the first and the second group pixels, and performs correction of reducing an influence caused by the A/D converter in the digital signals of the first group pixels using the correction value, thereby generating the image signal.
    Type: Application
    Filed: March 9, 2016
    Publication date: September 22, 2016
    Inventors: Katsuro Takenaka, Shinichi Takeda, Atsushi Iwashita, Sho Sato, Kosuke Terui, Yoshiaki Ishii
  • Patent number: 9445030
    Abstract: A radiation image capturing apparatus, comprising a sensor configured to monitor an irradiating dose of radiation, a switch configured output a sensor signal from the sensor, a readout unit configured to read out the sensor signal via a signal line, and a controlling unit, wherein the controlling unit performs first control of repeatedly performing, while the sensor is irradiated, a series of operations including a first operation of setting the switch to a conductive state and a second operation of setting the switch to a non-conductive state, second control of reading out the sensor signal in the first operation as a first signal and a potential of the signal line in the second operation as a second signal, and third control of calculating the irradiating dose of radiation based on the first signal and the second signal.
    Type: Grant
    Filed: July 16, 2015
    Date of Patent: September 13, 2016
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Tomoyuki Yagi, Toshio Kameshima, Katsuro Takenaka, Atsushi Iwashita, Eriko Sato, Hideyuki Okada, Takuya Ryu, Kosuke Terui
  • Patent number: 9423512
    Abstract: A radiation imaging apparatus includes a pixel array having pixels, a bias line applying a bias potential to converters of the pixels, a detection circuit which detects a current flowing to the bias line, and a control unit which detects a start of radiation irradiation to the pixel array based on an output from the detection circuit and controls a charge accumulation operation of the pixels in accordance with the detection. The detection circuit includes a differential amplifier circuit and a feedback path, and applies a potential corresponding to a reference bias potential to the bias line. The differential amplifier circuit includes a first input terminal receiving the reference bias potential, a second input terminal connected to the bias line, and an output terminal, and the feedback path connects the output terminal and the second input terminal.
    Type: Grant
    Filed: February 25, 2014
    Date of Patent: August 23, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventors: Eriko Sato, Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Hideyuki Okada, Sho Sato, Atsushi Iwashita, Takuya Ryu
  • Patent number: 9417333
    Abstract: A radiation imaging apparatus comprises: a detector that includes a detection unit in which pixels having a conversion element that converts radiation to an electric charge are arranged in a matrix shape, a drive circuit that drives the detection unit, and a read circuit that outputs an electric signal corresponding to the electric charge as image data; a radiation detection unit that detects a radiation irradiation state at a plurality of positions in the detection unit; and a control unit that controls operations of the drive circuit and the read circuit in accordance with a detection result obtained by the radiation detection unit, wherein the radiation detection unit detects a radiation irradiation state at least at a center region and a peripheral region in the detection unit, and a detection capability at the center region is set to a higher capability than a detection capability at the peripheral region.
    Type: Grant
    Filed: August 26, 2013
    Date of Patent: August 16, 2016
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Sho Sato, Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Hideyuki Okada, Atsushi Iwashita, Eriko Sugawara
  • Patent number: 9383453
    Abstract: A radiation imaging apparatus comprises: a detector that includes a detection unit in which pixels having a conversion element that converts radiation to an electric charge are arranged in a matrix shape, a drive circuit that drives the detection unit, and a read circuit that outputs an electric signal corresponding to the electric charge as image data; a radiation detection unit that detects a radiation irradiation state at a plurality of positions in the detection unit; and a control unit that controls operations of the drive circuit and the read circuit in accordance with a detection result obtained by the radiation detection unit, wherein the radiation detection unit detects a radiation irradiation state at least at a center region and a peripheral region in the detection unit, and a detection capability at the center region is set to a higher capability than a detection capability at the peripheral region.
    Type: Grant
    Filed: August 26, 2013
    Date of Patent: July 5, 2016
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Sho Sato, Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Hideyuki Okada, Atsushi Iwashita, Eriko Sugawara
  • Publication number: 20160178764
    Abstract: A radiation imaging system for performing a plurality of times of radiation imaging is provided. A readout circuit generates a value corresponding to a signal read out from each pixel. A control unit causes the readout circuit to generate a first pixel value corresponding to a signal read out from each pixel, and a first offset value of the readout circuit before starting the plurality of times of radiation imaging. The control unit causes the readout circuit to generate a second pixel value corresponding to a signal read out from each pixel, and a second offset value of the readout circuit during a plurality of times of radiation imaging. A correction unit corrects the second pixel value by using the first pixel value, the first offset value, and the second offset value.
    Type: Application
    Filed: December 15, 2015
    Publication date: June 23, 2016
    Inventors: Takuya Ryu, Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Atsushi Iwashita, Eriko Sato, Hideyuki Okada, Kosuke Terui
  • Patent number: 9360561
    Abstract: A radiation imaging apparatus includes a pixel array including a plurality of pixels arranged in a matrix in which each pixel includes a conversion element configured to convert radiation into a charge and a switch element configured to transfer an electric signal based on the charge, a plurality of wirings arranged in the pixel array, and a detecting unit configured to detect radiation irradiation to the pixel array, in which the detecting unit includes a detecting circuit configured to detect the radiation irradiation to the pixel array on the basis of a plurality of currents flowing through the plurality of wirings detected for each of the plurality of wirings.
    Type: Grant
    Filed: March 15, 2013
    Date of Patent: June 7, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsuro Takenaka, Toshio Kameshima, Tomoyuki Yagi, Hideyuki Okada, Sho Sato, Atsushi Iwashita, Eriko Sugawara
  • Patent number: 9360562
    Abstract: To provide a radiation imaging apparatus and a radiation imaging system that can detect radiation with high accuracy, the radiation imaging apparatus includes: a detection unit in which conversion elements that convert radiation into an electric signal are arranged in a matrix shape; a radiation detection unit configured to detect an irradiation state of radiation; a drive circuit configured to drive the detection unit in accordance with the irradiation state detected by the radiation detection unit; and a radiographing kind setting unit configured to set a radiographing kind, wherein the radiation detection unit changes a radiation detection capability in accordance with the radiographing kind set by the radiographing kind setting unit.
    Type: Grant
    Filed: August 23, 2013
    Date of Patent: June 7, 2016
    Assignee: CANON KABUSHIKI KAISHA
    Inventors: Sho Sato, Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Hideyuki Okada, Atsushi Iwashita, Eriko Sugawara
  • Publication number: 20160134818
    Abstract: A radiation imaging system capable of obtaining excellent image quality is provided.
    Type: Application
    Filed: July 7, 2014
    Publication date: May 12, 2016
    Inventors: Atsushi Iwashita, Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Hideyuki Okada, Sho Sato, Eriko Sato, Takuya Ryu
  • Patent number: 9329280
    Abstract: A radiation image pickup apparatus includes a pixel array having pixels each including a conversion element and a switch element, a drive circuit for controlling the switch element between a conducting state and a non-conducting state, a detection unit for outputting a detection signal varying with the intensity of irradiation of the pixel array, and an arithmetic unit for calculating a start threshold value used to detect start of irradiation based on the signal output from the detection unit during a period when radiation is not emitted onto the pixel array in which the switch elements are sequentially set in a conducting state on a row-by-row basis by the drive circuit and the signal output from the detection unit during a period when radiation is emitted onto the pixel array in which the switch elements are sequentially set in a conducting state on a row-by-row basis by the drive circuit.
    Type: Grant
    Filed: July 3, 2013
    Date of Patent: May 3, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Sho Sato, Atsushi Iwashita, Eriko Sugawara, Hideyuki Okada
  • Publication number: 20160084969
    Abstract: A radiation imaging apparatus includes a pixel array where a plurality of pixels configured to detect radiation are arrayed, a sensor configured to detect radiation irradiation for exposure control, a reader configured to read out signals from the plurality of pixels and the sensor, and a processor configured to process the signals read out by the reader. The processor corrects, based on the signals read out from the sensor by the reader, the signals read out from the plurality of pixels by the reader.
    Type: Application
    Filed: September 10, 2015
    Publication date: March 24, 2016
    Inventors: Eriko Sato, Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Atsushi Iwashita, Hideyuki Okada, Takuya Ryu, Kosuke Terui
  • Patent number: 9288409
    Abstract: An image pickup apparatus includes a detector and an image processing unit. The detector executes image pickup operations in which electrical signals based on radiation are output and executes, in a period between a first image pickup operation and a second image pickup operation, a first inter-image pickup operation for suppressing a lag generated by the first image pickup operation and a second inter-image pickup operation for obtaining dark signals from the detector after the first inter-image pickup operation. The signal processing unit calculates a correction coefficient using a first time ts, a second time te, and the dark signals, predicts an amount of offset to be included in electrical signals of the second image pickup operation using a third time ts?, a fourth time te?, and the correction coefficient, and executes calculation using the electrical signals and the amount of offset output from the detector in the second image pickup operation.
    Type: Grant
    Filed: December 20, 2012
    Date of Patent: March 15, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventors: Atsushi Iwashita, Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Hideyuki Okada, Sho Sato, Eriko Sugawara
  • Patent number: 9247163
    Abstract: A radiation image pickup system includes a correction coefficient calculation unit that calculates a correction coefficient using pixel output values of a plurality of pixels, and a correction unit that corrects pixel output values of a plurality of pixels using the correction coefficient. A drive control unit repeatedly resets an electric charge caused by a dark current of a plurality of pixels until a detection unit detects a start of radiation exposure. The reset operation is performed simultaneously for n rows that are not adjacent to each other, where n is an integer equal to or greater than 2. The correction coefficient calculation unit calculates the correction coefficient using pixel output values of pixels in a row subjected to the reset operation in a period from a start of radiation exposure to a start detection time and pixel output values of pixels in an adjacent row.
    Type: Grant
    Filed: March 18, 2014
    Date of Patent: January 26, 2016
    Assignee: Canon Kabushiki Kaisha
    Inventors: Sho Sato, Toshio Kameshima, Tomoyuki Yagi, Katsuro Takenaka, Hideyuki Okada, Atsushi Iwashita, Eriko Sato, Takuya Ryu