公开(公告)号：US20210106292A1

公开(公告)日：2021-04-15

申请号：US16876185

申请日：2020-05-18

Applicant: Hitachi, Ltd.

Inventor： Shinichi KOJIMA ,  Kazuma YOKOI ,  Isao TAKAHASHI ,  Fumito WATANABE ,  Fuyuhiko TERAMOTO ,  Taiga GOTOU

IPC: A61B6/03 ,  A61B6/00

Abstract: A material decomposition apparatus for performing decomposition of a material in an object. The apparatus includes a data storage section for storing correction data preliminarily generated by decomposing one of three or more materials into the other two materials, a data input section to which radiation data of the object is inputted, the radiation data being divided into a plurality of energy levels, and a decomposition processing section for repeatedly performing two-material decomposition for decomposition of the other two materials of the three or more materials using the radiation data at different energy levels and the correction data to perform decomposition of the inside of the object into the three or more materials.

公开(公告)号：US20200323502A1

公开(公告)日：2020-10-15

申请号：US16305777

申请日：2017-09-08

Applicant: HITACHI, LTD.

Inventor： Shinichi KOJIMA ,  Fumito WATANABE ,  Yasutaka KONNO ,  Isao TAKAHASHI ,  Kazuma YOKOI

IPC: A61B6/00 ,  A61B6/03 ,  A61B6/02

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.

公开(公告)号：US20190021685A1

公开(公告)日：2019-01-24

申请号：US16071810

申请日：2016-11-17

Applicant: Hitachi, Ltd.

Inventor： Shinichi KOJIMA ,  Yasutaka KONNO ,  Fumito WATANABE ,  Isao TAKAHASHI

IPC: A61B6/00 ,  A61B6/03 ,  G06T11/00

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.

公开(公告)号：US20170176609A1

公开(公告)日：2017-06-22

申请号：US15325497

申请日：2015-07-23

Applicant: HITACHI, LTD.

Inventor： Yushi TSUBOTA ,  Shinji KUROKAWA ,  Keisuke YAMAKAWA ,  Yasutaka KONNO ,  Shinichi KOJIMA ,  Fumito WATANABE

IPC: G01T1/29 ,  G01N23/04 ,  A61B6/00 ,  A61B6/03

CPC classification number: G01T1/2985 ,  A61B6/032 ,  A61B6/4233 ,  G01N23/046

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.

公开(公告)号：US20200225368A1

公开(公告)日：2020-07-16

申请号：US16719528

申请日：2019-12-18

Applicant: Hitachi, Ltd.

Inventor： Masafumi ONOUCHI ,  Takafumi ISHITSU ,  Fumito WATANABE

IPC: G01T1/24 ,  G01T1/17 ,  H01J37/244 ,  G01T1/29

Abstract: The present invention provides a radiation imaging apparatus capable of maintaining the quality of an image obtained even when a dose incident on a radiation detector changes suddenly. The present invention is a radiation imaging apparatus including a radiation source, a radiation detector to detect radiation emitted from the radiation source, and a cooling unit to cool the radiation detector; and is characterized in that the radiation detector has a counting circuit to output a number of photons in radiation counted per unit time as a photon counting rate, and the cooling unit controls a coolability of the radiation detector in response to the photon counting rate.

公开(公告)号：US20200015769A1

公开(公告)日：2020-01-16

申请号：US16439748

申请日：2019-06-13

Applicant: Hitachi, Ltd.

Inventor： Shinichi KOJIMA ,  Fumito WATANABE ,  Kazuma YOKOI ,  Fuyuhiko TERAMOTO

IPC: A61B6/00

Abstract: To provide an X-ray CT apparatus capable of correcting a difference of scattered radiation quantities contained in the projection data even in a case where a plurality of detection elements are disposed between collimator plates. The X-ray CT apparatus includes: an X-ray irradiation section for X-ray radiation; an X-ray detector including a plurality of detection elements for detecting the X-ray; a plurality of collimator plates disposed between the X-ray irradiation section and the X-ray detector so as to reduce scattered radiation; a reconstruction portion for reconstructing a tomographic image by using projection data generated based on an output from the X-ray detector; and a correction portion for correcting the projection data by using different correction functions according to the positions of the plural detection elements disposed between the collimator plates.

公开(公告)号：US20170276808A1

公开(公告)日：2017-09-28

申请号：US15518575

申请日：2015-06-18

Applicant: HITACHI, LTD.

Inventor： Isao TAKAHASHI ,  Kazuma YOKOI ,  Eiji MORO ,  Yuichiro UENO ,  Yasutaka KONNO ,  Fumito WATANABE ,  Shinichi KOJIMA

IPC: G01T1/29 ,  H01L31/115 ,  H01L27/146 ,  G01T1/161 ,  G01T1/20

CPC classification number: G01T1/2985 ,  A61B6/032 ,  A61B6/4208 ,  G01T1/161 ,  G01T1/17 ,  G01T1/2018 ,  H01L27/14658 ,  H01L31/115

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).