WO2013027536A1 - Dispositif de radiographie et procédé de radiographie - Google Patents

Dispositif de radiographie et procédé de radiographie Download PDF

Info

Publication number
WO2013027536A1
WO2013027536A1 PCT/JP2012/069136 JP2012069136W WO2013027536A1 WO 2013027536 A1 WO2013027536 A1 WO 2013027536A1 JP 2012069136 W JP2012069136 W JP 2012069136W WO 2013027536 A1 WO2013027536 A1 WO 2013027536A1
Authority
WO
WIPO (PCT)
Prior art keywords
image
grating
region
phase differential
offset
Prior art date
Application number
PCT/JP2012/069136
Other languages
English (en)
Japanese (ja)
Inventor
拓司 多田
Original Assignee
富士フイルム株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 富士フイルム株式会社 filed Critical 富士フイルム株式会社
Publication of WO2013027536A1 publication Critical patent/WO2013027536A1/fr

Links

Images

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B6/00—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
    • A61B6/48—Diagnostic techniques
    • A61B6/484—Diagnostic techniques involving phase contrast X-ray imaging
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B6/00—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
    • A61B6/52—Devices using data or image processing specially adapted for radiation diagnosis
    • A61B6/5211—Devices using data or image processing specially adapted for radiation diagnosis involving processing of medical diagnostic data
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B6/00—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
    • A61B6/52—Devices using data or image processing specially adapted for radiation diagnosis
    • A61B6/5258—Devices using data or image processing specially adapted for radiation diagnosis involving detection or reduction of artifacts or noise
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
    • G01N23/20—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by using diffraction of the radiation by the materials, e.g. for investigating crystal structure; by using scattering of the radiation by the materials, e.g. for investigating non-crystalline materials; by using reflection of the radiation by the materials
    • G01N23/20075—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by using diffraction of the radiation by the materials, e.g. for investigating crystal structure; by using scattering of the radiation by the materials, e.g. for investigating non-crystalline materials; by using reflection of the radiation by the materials by measuring interferences of X-rays, e.g. Borrmann effect
    • G—PHYSICS
    • G16—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR SPECIFIC APPLICATION FIELDS
    • G16H—HEALTHCARE INFORMATICS, i.e. INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR THE HANDLING OR PROCESSING OF MEDICAL OR HEALTHCARE DATA
    • G16H50/00—ICT specially adapted for medical diagnosis, medical simulation or medical data mining; ICT specially adapted for detecting, monitoring or modelling epidemics or pandemics
    • G16H50/20—ICT specially adapted for medical diagnosis, medical simulation or medical data mining; ICT specially adapted for detecting, monitoring or modelling epidemics or pandemics for computer-aided diagnosis, e.g. based on medical expert systems
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B6/00—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment
    • A61B6/42—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment with arrangements for detecting radiation specially adapted for radiation diagnosis
    • A61B6/4291—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment with arrangements for detecting radiation specially adapted for radiation diagnosis the detector being combined with a grid or grating
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2223/00—Investigating materials by wave or particle radiation
    • G01N2223/30—Accessories, mechanical or electrical features
    • G01N2223/313—Accessories, mechanical or electrical features filters, rotating filter disc
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2223/00—Investigating materials by wave or particle radiation
    • G01N2223/40—Imaging
    • G01N2223/401—Imaging image processing

Definitions

  • the present invention relates to a radiation imaging apparatus and a radiation imaging method for detecting an image based on a phase change of radiation.
  • Radiation such as X-rays
  • X-rays has a characteristic of decaying depending on the weight (atomic number) of the elements constituting the substance and the density and thickness of the substance. Focusing on this characteristic, X-rays are used as a probe for seeing through the inside of a subject in fields such as medical diagnosis and nondestructive inspection.
  • a general X-ray imaging apparatus includes an X-ray source that emits X-rays and an X-ray image detector that detects X-rays.
  • an X-ray source that emits X-rays
  • an X-ray image detector that detects X-rays.
  • the X-rays emitted from the X-ray source are absorbed when passing through the subject, and enter the X-ray image detector in a state where the intensity is attenuated.
  • an image representing an X-ray intensity change by the subject is detected by the X-ray image detector.
  • the X-ray absorption ability is lower with an element having a smaller atomic number, there is a problem that a change in X-ray intensity is small and a sufficient contrast cannot be obtained in an image in a soft body tissue or soft material.
  • most of the components of the cartilage part constituting the joint of the human body and the joint fluid in the vicinity thereof are water, and the difference in X-ray absorption capacity between the two is small, so that it is difficult to obtain contrast.
  • X-ray phase imaging is a method of imaging the phase change of X-rays, focusing on the fact that the phase change of X-rays incident on the subject is larger than the intensity change. Can also obtain a high-contrast image.
  • an X-ray imaging apparatus in which first and second gratings are arranged in parallel at a predetermined interval between an X-ray source and an X-ray image detector. (For example, refer to Patent Document 1).
  • the first periodic pattern image is generated when the X-ray source passes through the first grating, and the second grating partially shields the first periodic pattern image.
  • Two periodic pattern images are generated.
  • the X-ray image detector detects the second periodic pattern image and generates image data.
  • the subject is disposed, for example, between the X-ray source and the first grating, and the subject undergoes a phase change in the X-ray, thereby modulating the first periodic pattern image. By detecting this modulation amount through the second periodic pattern image, the X-ray phase change can be imaged.
  • This method is called the fringe scanning method.
  • the second grating is intermittently moved in the direction parallel to the plane of the first grating and perpendicular to the grating line direction of the first grating with respect to the first grating.
  • Image data is generated by shooting during the stop.
  • an intensity modulation signal representing an intensity change accompanying the movement of the second lattice is generated for each pixel.
  • the phase shift amount of the intensity modulation signal (the phase shift amount from the case where the subject does not exist) is calculated, and the phase shift amount is imaged to obtain an image representing the modulation amount. Since this image represents the differential amount of the phase change (phase shift) of the X-rays by the subject, it is called a phase differential image.
  • the phase shift amount of the intensity modulation signal is calculated by using a function (arg vein) for extracting a complex argument or an arctangent function (tan -1 vein). Since the phase differential image is calculated, the phase differential image is expressed by a value convolved (wrapped) in the range of the function used for the calculation (from ⁇ to + ⁇ or from ⁇ / 2 to + ⁇ / 2). . In the phase differential image wrapped in this way, jumps (discontinuous points) corresponding to the above-described range occur at locations where the upper limit of the range changes from the lower limit or locations where the lower limit changes to the upper limit. For this reason, the wrapped phase differential image is subjected to an unwrap process for eliminating the discontinuity and making it continuous (for example, see Patent Document 2).
  • unwrap processing is performed in order along a predetermined route from a predetermined position in the image as a starting point (for example, refer to Patent Document 3).
  • the discontinuous point is determined by uniformly adding or subtracting a value corresponding to the range of the function to data on the path after the discontinuous point. It becomes continuous without.
  • the high-absorber has a large amount of X-ray attenuation, and the intensity and amplitude of the intensity modulation signal are reduced.
  • the calculation accuracy of the phase shift amount decreases.
  • an unwrapping error is likely to occur in the region of the phase differential image corresponding to the high absorber.
  • This unwrapping error includes a case where it is erroneously determined as a discontinuous point and an unwrapping process is performed, and a case where it is erroneously determined that it is not a discontinuous point and an unwrapping process is not performed.
  • the wrapping phase differential image when the starting point is set in the region of the bone part that is a high absorber, and unwrap processing is performed along a path that goes downward from the starting point, Unwrap errors are likely to occur in the bone region.
  • an error value (a value corresponding to the range of the above function) is sequentially added to or subtracted from the path after that point.
  • the phase differential image after the unwrap process has a difference in the path direction of the unwrap process.
  • a streak of noise along the line occurs. This streak noise overlaps with a soft tissue (cartilage portion) that is a target portion of X-ray phase imaging, and obstructs imaging of the soft tissue.
  • NG region region where an unwrapping error is likely to occur from the phase differential image and unwrapping only the other region (OK region)
  • NG region region where an unwrapping error is likely to occur from the phase differential image and unwrapping only the other region (OK region)
  • the phase differential image is divided into NG regions and there are a plurality of OK regions in the phase differential image
  • each OK region is individually unwrapped, as shown in FIG.
  • a step is generated in the pixel value between the OK regions.
  • An object of the present invention is to provide a radiation imaging apparatus and a radiation imaging method capable of reducing unwrapping errors and improving offset correction.
  • a radiation imaging apparatus of the present invention includes a radiation detector, a grating unit, a phase differential image generation unit, an offset image storage unit, an OK / NG region detection unit, and a first unwrap.
  • a processing unit, a second unwrap processing unit, and an offset processing unit are provided.
  • the radiation detector detects the radiation emitted from the radiation source and transmitted through the subject to generate image data.
  • the grating portion is disposed between the radiation source and the radiation detector.
  • the phase differential image generation unit generates a phase differential image represented by a value wrapped in a predetermined range based on the image data.
  • the offset image storage unit stores, as an offset image, the phase differential image generated by the phase differential image generation unit without placing the subject.
  • the OK / NG region detection unit detects an NG region in which an unwrap error is likely to occur from the phase differential image generated by the phase differential image generation unit in a state where the subject is arranged, and sets other regions as OK regions. An area in the offset image corresponding to this OK area is defined as an OK area.
  • the first unwrap processing unit unwraps only the OK region of the phase differential image. When there are a plurality of OK regions, the second unwrap processing unit unwraps only each OK region of the offset image, and when there is only one OK region, the entire offset image or only the OK region. Is unwrapped.
  • the offset processing unit subtracts the offset image subjected to the unwrap processing by the second unwrap processing unit from the phase differential image subjected to the unwrap processing by the first unwrap processing unit.
  • the second unwrap processing unit preferably unwraps only the OK region of the offset image when there is only one OK region.
  • the first unwrap processing unit and the second unwrap processing unit perform the unwrap process by setting the same starting point for each OK region.
  • the difference between the pixel values of the start points is calculated for the phase differential image that has been unwrapped by the first unwrap processor and the offset image that has been unwrapped by the second unwrap processor, and this It is preferable to further include a calibration processing unit that calibrates the OK region of the offset image based on the difference.
  • the image processing apparatus may further include a correction processing unit that generates correction data by fitting noise remaining in the phase differential image subjected to offset correction in a linear format or a polynomial, and removes noise using the correction data. preferable.
  • the first and second unwrap processing units set starting points in order along penetrating lines that pass through only the OK region and pass through the phase differential image in one direction, and follow a straight path perpendicular to the penetrating line from each starting point. It is preferable to perform unwrapping processing, unwrapping processing between each starting point, and unwrapping processing for pixels in the OK region remaining behind the NG region when viewed from each starting point.
  • the grating unit partially shields the first periodic pattern image by passing the radiation from the radiation source to generate the first periodic pattern image, and the second periodic pattern image. It is preferable to have the second grating to be generated.
  • the radiation image detector detects the second periodic pattern image and generates image data.
  • the phase differential image generation unit may generate a phase differential image based on single image data obtained by the radiation detector.
  • the grating unit further includes a scanning mechanism that moves the first grating or the second grating at a predetermined scanning pitch and sequentially sets the plurality of scanning positions.
  • the radiological image detector detects the second periodic pattern image at each scanning position to generate image data
  • the phase differential image generation unit includes a plurality of radiographic image detectors generated by the radiographic image detector at the plurality of scanning positions. A phase differential image is generated based on the image data.
  • the scanning mechanism moves the first grating or the second grating in a direction perpendicular to the grating line.
  • the scanning mechanism may move the first grating or the second grating in a direction inclined with respect to the grating line.
  • the OK / NG region detection unit includes the average intensity, amplitude, and visibility of the intensity modulation signal representing the intensity change of the pixel value of the image data with respect to the position of the first grating or the second grating moved by the scanning mechanism.
  • the NG region is detected based on one or more combinations.
  • the image processing apparatus may further include an NG region image replacement unit that replaces the NG region of the phase differential image using any one of an absorption image, a differential image of the absorption image, and a small-angle scattering image created based on the intensity modulation signal. preferable.
  • the first grating is an absorption grating, and it is preferable that the first periodic pattern image is generated by geometrically optically projecting incident radiation. Further, the first grating may be an absorption grating or a phase grating, and may generate a first periodic pattern image by causing a Talbot effect to incident radiation.
  • a multi-slit that partially blocks the radiation emitted from the radiation source and disperses the focal point.
  • the radiation imaging method of the present invention includes a main imaging process, a pre-imaging process, an OK / NG area detection process, a first unwrap process process, a second unwrap process process, and an offset process process.
  • this imaging process in a state in which the subject is arranged, the radiation emitted from the radiation source and detected through the subject and the lattice part is generated to generate image data. Based on this image data, the image data is wrapped in a predetermined range. The phase differential image represented by the obtained value is generated.
  • the pre-imaging process in a state where the subject is not arranged, the radiation emitted from the radiation source and detected through the lattice portion is generated to generate image data.
  • the value is wrapped in a predetermined range.
  • a represented phase differential image is generated and stored as an offset image.
  • the OK / NG area detection step an NG area where an unwrapping error is likely to occur is detected from the phase differential image generated in the main imaging process, and other areas are set as OK areas, and the offset image corresponding to the OK area is included in the OK image. This area is the OK area.
  • the OK processing step only the OK region of the phase differential image generated in the main photographing step is unwrapped.
  • the second unwrap processing step when there are a plurality of OK regions, only each OK region of the offset image is unwrapped. When there is only one OK region, the entire offset image or only the OK region is processed. Is unwrapped.
  • the offset processing step performs offset correction for subtracting the offset image that has been unwrapped in the second unwrapping step from the phase differential image that has been unwrapped in the first unwrapping step.
  • an NG region in which an unwrap error is likely to occur is detected from the phase differential image, the other region is set as an OK region, and the region in the offset image corresponding to this OK region is set as the OK region.
  • Only the OK region is unwrapped for the phase differential image generated in the actual photographing.
  • only the OK regions are unwrapped, and when there is only one OK region, the entire offset image is processed.
  • only the OK area is unwrapped.
  • an X-ray imaging apparatus 10 includes an X-ray source 11, a grating unit 12, an X-ray image detector 13, a memory 14, an image processing unit 15, an image recording unit 16, an imaging control unit 17, a console 18, and a system.
  • a control unit 19 is provided.
  • the X-ray source 11 includes a rotary anode type X-ray tube (not shown) and a collimator (not shown) for limiting the X-ray irradiation field, and is controlled by the imaging control unit 17. Based on the above, X-rays are emitted toward the subject H.
  • the grating unit 12 includes a first grating 21, a second grating 22, and a scanning mechanism 23.
  • the first and second gratings 21 and 22 are disposed to face the X-ray source 11 in the Z direction, which is the X-ray irradiation direction.
  • a space is provided between the X-ray source 11 and the first grating 21 so that the subject H can be arranged.
  • the X-ray image detector 13 is a flat panel detector using a semiconductor circuit, and is disposed close to the back of the second grating 22.
  • the detection surface 13a of the X-ray image detector 13 exists on the XY plane orthogonal to the Z direction.
  • the first lattice 21 has a lattice plane on the XY plane, and a plurality of X-ray absorption portions 21a and X-ray transmission portions 21b extending in the Y direction (lattice direction) are formed on the lattice plane. .
  • the X-ray absorption parts 21a and the X-ray transmission parts 21b are alternately arranged along the X direction to form a striped pattern.
  • the second grating 22 includes a plurality of X-ray absorption parts 22 a and X-ray transmission parts 22 b that extend in the Y direction and are alternately arranged along the X direction.
  • the X-ray absorbing portions 21a and 22a are formed of a metal having X-ray absorption properties such as gold (Au) and platinum (Pt).
  • the X-ray transmissive portions 21b and 22b are formed of an X-ray transmissive material such as silicon (Si) or resin, or a gap.
  • the first grating 21 partially passes the X-rays emitted from the X-ray source 11 to generate a first periodic pattern image (hereinafter referred to as a G1 image).
  • This G1 image substantially coincides with the lattice pattern of the second lattice 22 at the position of the second lattice 22.
  • the second grating 22 partially shields the G1 image generated by the first grating 21 to generate a second periodic pattern image (hereinafter referred to as G2 image).
  • the X-ray image detector 13 detects the G2 image and generates image data.
  • the memory 14 temporarily stores the image data read from the X-ray image detector 13.
  • the image processing unit 15 generates a phase differential image based on the image data stored in the memory 14, and generates a phase contrast image based on the phase differential image.
  • the image recording unit 16 records a phase differential image and a phase contrast image.
  • the scanning mechanism 23 intermittently moves the second grating 22 in the X direction, and changes the position (scanning position) of the second grating 22 with respect to the first grating 21 in a stepwise manner.
  • the drive unit of the scanning mechanism 23 is configured by a piezoelectric actuator or an electrostatic actuator, and is driven based on the control of the imaging control unit 17 at the time of stripe scanning described later.
  • the memory 14 stores image data obtained by the X-ray image detector 13 at each scanning position of the second grating 22 with respect to the first grating 21.
  • the console 18 includes an operation unit 18a and a monitor 18b.
  • the operation unit 18a is configured by a keyboard, a mouse, and the like, and sets imaging conditions such as tube voltage, tube current, and irradiation time of the X-ray source 11, selection of an imaging mode (main imaging or pre-imaging), imaging execution instruction, and the like.
  • the operation input can be performed.
  • the main imaging is an imaging mode performed with the subject H placed between the X-ray source 11 and the first grating 21.
  • Pre-imaging is an imaging mode performed without placing the subject H between the X-ray source 11 and the first grating 21.
  • the pre-photographing is used to acquire a background component (offset image) caused by a manufacturing error or arrangement error of the first and second gratings 21 and 22.
  • the monitor 18b displays photographing information such as photographing conditions, and a phase differential image and a phase contrast image recorded in the image recording unit 16.
  • the system control unit 19 comprehensively controls each unit according to a signal input from the operation unit 18a.
  • the X-ray image detector 13 includes a plurality of pixels 30 arranged two-dimensionally, a gate scanning line 33, a scanning circuit 34, a signal line 35, and a readout circuit 36.
  • the pixel 30 includes a pixel electrode 31 for collecting charges generated in a semiconductor film such as amorphous selenium (a-Se) by incident X-rays, and a TFT (for reading the charges collected by the pixel electrode 31).
  • a-Se amorphous selenium
  • TFT Thin Film Transistor
  • the gate scanning line 33 is provided for each row of the pixels 30.
  • the scanning circuit 34 applies a scanning signal for turning on / off the TFT 32 to each gate scanning line 33.
  • the signal line 35 is provided for each column of the pixels 30.
  • the readout circuit 36 reads out electric charges from the pixels 30 through the signal lines 35, converts them into image data, and outputs them.
  • the detailed layer configuration of each pixel 30 is the same as the layer configuration described in Japanese Patent Laid-Open No. 2002-26300.
  • the readout circuit 36 includes an integration amplifier, an A / D converter, a correction circuit (none of which is shown), and the like.
  • the integrating amplifier integrates the charges output from each pixel 30 through the signal line 35 to generate an image signal.
  • the A / D converter converts the image signal generated by the integrating amplifier into digital image data.
  • the correction circuit performs dark current correction, gain correction, linearity correction, and the like on the image data, and inputs the corrected image data to the memory 14.
  • the X-ray image detector 13 is not limited to a direct conversion type that directly converts incident X-rays into electric charges, but converts incident X-rays into visible light with a scintillator such as cesium iodide (CsI) or gadolinium oxysulfide (GOS). Alternatively, an indirect conversion type in which visible light is converted into electric charge by a photodiode may be used.
  • the X-ray image detector 13 is not limited to a radiographic image detector based on a TFT panel, and a radiographic image detector based on a solid-state imaging device such as a CCD sensor or a CMOS sensor can also be used. .
  • X-rays irradiated from the X-ray source 11 are cone beams having the X-ray focal point 11a as a light emitting point.
  • the first grating 21 is configured to project the X-rays that have passed through the X-ray transmission part 21b substantially geometrically.
  • the width of the X-ray transmission part 21b in the X direction is set to a value sufficiently larger than the effective wavelength of X-rays radiated from the X-ray source 11, and straightness is achieved without diffracting most of the X-rays. It is realized by letting it pass while keeping.
  • the effective wavelength of X-rays is about 0.4 mm.
  • the width of the X-ray transmission part 21b may be about 1 to 10 ⁇ m. The same applies to the second grating 22.
  • the G1 image generated by the first grating 21 expands in proportion to the distance from the X-ray focal point 11a.
  • the grating pitch p 2 of the second grating 22 is determined so as to coincide with the periodic pattern of the G1 image at the position of the second grating 22.
  • the grating pitch p 2 of the second grating 22 is the grating pitch of the first grating 21 p 1 , the distance L 1 between the X-ray focal point 11 a and the first grating 21, the first grating 21.
  • the coordinates in the X, Y, and Z directions are x, y, and z.
  • the G1 image is modulated by the phase change in the X-ray caused by the subject H.
  • the modulation amount reflects the X-ray refraction angle ⁇ (x) of the subject H.
  • FIG. 3 illustrates an X-ray path emitted from the X-ray focal point 11a.
  • Reference numeral X1 indicates a path along which the X-ray goes straight when the subject H does not exist.
  • X-rays traveling along the path X 1 pass through the first and second gratings 21 and 22 and enter the X-ray image detector 13.
  • Reference numeral X2 indicates an X-ray path refracted by the subject H when the subject H exists.
  • X-rays traveling along the path X ⁇ b> 2 pass through the first grating 21 and are then absorbed by the X-ray absorption unit 22 a of the second grating 22.
  • phase shift distribution ⁇ (x) representing the amount of X-ray phase change by the subject H.
  • This phase shift distribution ⁇ (x) is expressed by the following equation (2), where X-ray wavelength is ⁇ and refractive index distribution of the subject H is n (x, z).
  • the y-coordinate is omitted for simplification of description.
  • This phase shift distribution ⁇ (x) is in the relationship of the refraction angle ⁇ (x) of X-ray and the following equation (3).
  • the amount of displacement ⁇ x in the X direction at the position of the second grating 22 between the X-ray traveling along the path X1 and the X-ray traveling along the path X2 is based on the fact that the refraction angle ⁇ (x) of the X-ray is very small. It is approximately represented by the following formula (4).
  • the displacement ⁇ x is proportional to the differential value of the phase shift distribution ⁇ (x).
  • This displacement amount ⁇ x can be detected by a fringe scanning method, and as a result, a phase differential image is obtained.
  • a value obtained by dividing the grating pitch p 2 into M pieces (p 2 / M) is set as a scanning pitch, and the scanning mechanism 23 intermittently moves the second grating 22 in the X direction at this scanning pitch. By doing so, fringe scanning is performed.
  • X-rays are emitted from the X-ray source 11 and a G2 image is detected by the X-ray image detector 13.
  • M pieces of image data are obtained, and M pixel values are obtained for each pixel 30 of the X-ray image detector 13.
  • the scanning position k is a position that is discrete in the X direction by a scanning pitch (p 2 / M).
  • a signal representing a change in the pixel value I k with respect to the scanning position k is referred to as an intensity modulation signal.
  • the broken line in the figure shows an intensity modulation signal obtained by pre-imaging (a state where the subject H is not arranged).
  • the solid line indicates the intensity modulation signal in which the phase shift amount ⁇ (x) is generated by the subject H in the main imaging (the state where the subject H is arranged).
  • This phase shift amount ⁇ (x) is in the relationship of the displacement amount ⁇ x and the following equation (5).
  • a phase differential image is obtained by obtaining the phase shift amount ⁇ (x) of the intensity modulation signal based on the M pixel values I k obtained by the fringe scanning.
  • the intensity modulation signal is generally expressed by the following formula (6).
  • a 0 represents the average intensity of the incident X-ray
  • a n represents the amplitude of the intensity-modulated signal.
  • N is a positive integer
  • phase shift amount ⁇ (x) is represented by the following equation (8).
  • arg vein is a function that extracts the argument of a complex number.
  • phase shift amount ⁇ (x) can also be expressed by the following equation (9) using an arctangent function.
  • the phase shift amount ⁇ (x) is ⁇ Take a value that is convolved (wrapped) in the range of ⁇ to + ⁇ .
  • the range of the arc tangent function is usually in the range of ⁇ / 2 to + ⁇ / 2
  • the phase shift amount ⁇ (x) is calculated based on the above equation (9)
  • the phase shift amount ⁇ (x) takes a value convolved in a range of ⁇ / 2 to + ⁇ / 2.
  • the range of the arc tangent function can be expanded from ⁇ to + ⁇ by determining the denominator and the sign of the numerator in the arc tangent function. Therefore, the phase shift amount ⁇ (x) can be calculated in the range of ⁇ to + ⁇ based on the above equation (9).
  • phase differential image an image represented by data obtained by calculating the phase shift amount ⁇ (x) for each pixel 30 is referred to as a phase differential image.
  • an image represented by data obtained by multiplying or adding a phase shift amount ⁇ (x) by a constant may be a phase differential image.
  • the image processing unit 15 includes a phase differential image generation unit 40, an offset image storage unit 41, an OK / NG region detection unit 42, a first unwrap processing unit 43, a second unwrap processing unit 44, and an offset processing unit. 45 and a phase contrast image generation unit 46.
  • the phase differential image generation unit 40 uses M image data acquired by fringe scanning and stored in the memory 14 in main photographing or pre-photographing, and performs calculation based on the above equation (8) or the above equation (9). By doing so, a phase differential image is generated.
  • the phase differential image generated by the phase differential image generation unit 40 at the time of pre-photographing is stored in the offset image storage unit 41 as an offset image.
  • the phase differential image generated by the phase differential image generation unit 40 during the main photographing is input to the first unwrap processing unit 43.
  • the offset image storage unit 41 deletes the stored offset image and then stores the input offset image.
  • the OK / NG area detection unit 42 detects an area (hereinafter referred to as an NG area) in which an unwrapping error is likely to occur in the phase differential image based on the M image data stored in the memory 14 at the time of actual photographing.
  • the area other than is set as the OK area, and the area in the offset image corresponding to the OK area is set as the OK area.
  • This NG region corresponds to a high-absorber region included in the subject H (such as a bone portion having a high X-ray absorption ability when the subject H is a human body). This is based on the fact that the average intensity A 0 , the amplitude A 1 , or the visibility A 1 / A 0 decreases due to the X-rays being absorbed by the high absorber.
  • the NG region may be detected by combining two or more of the average intensity A 0 , the amplitude A 1 , and the visibility A 1 / A 0 .
  • the size of the detected NG region may be adjusted by changing the threshold value.
  • the first unwrap processing unit 43 unwraps only the OK region for the phase differential image input from the phase differential image generation unit 40.
  • the second unwrap processing unit 44 unwraps the entire image or only the OK region with respect to the offset image stored in the offset image storage unit 41.
  • the offset processing unit 45 performs offset correction by subtracting the offset image subjected to the unwrap processing by the second unwrap processing unit 44 from the phase differential image subjected to the unwrap processing by the first unwrap processing unit 43. Specifically, the pixel value is subtracted within the corresponding pixel 30.
  • the phase contrast image generation unit 46 generates a phase contrast image representing the phase shift distribution by integrating the phase differential image after the offset correction along the X direction.
  • the phase differential image (difference image) after the offset correction and the phase contrast image are recorded in the image recording unit 16.
  • FIG. 7 shows the phase differential image as an image of 10 ⁇ 7 pixels for the sake of simplicity of explanation.
  • the NG area detected by the OK / NG area detection unit 42 is shown.
  • the OK area is an area other than the NG area.
  • the starting point for starting the unwrapping process is set for each row or column of the phase differential image (step S10).
  • a through line that passes only through the OK region and penetrates the phase differential image in the X direction or the Y direction is searched, and a starting point is set along one of the through lines.
  • the penetrating lines along the shorter Y direction are given priority, and starting points P0 to P6 are set in one of them.
  • the starting points P0 to P6 are set along the X direction end (short side) of the phase differential image.
  • linear straight paths R0 to R6 having the starting points P0 to P6 as starting points in a direction (X direction) orthogonal to the through line where the starting points P0 to P6 are set. Is set, and the unwrapping process is executed along each of the straight paths R0 to R6 (step S11). These straight paths R0 to R6 are not set in the NG area. Therefore, behind the NG area viewed from the starting points P0 to P6, pixels that belong to the same OK area as the starting points P0 to P6 but do not have the straight paths R0 to R6 set remain.
  • step S11 first, unwrap processing is performed in order along the straight line route R0 from the starting point P0, and when the unwrap processing of the straight line route R0 ends, the unwrapping processing of the starting point P1 is performed with reference to the starting point P0. Thereafter, the unwrapping process is sequentially performed from the starting point P1 along the straight path R1. Then, the unwrapping process is not performed on the pixels remaining behind the NG area in the same row as the straight line R1, and the unwrapping process of the starting point P2 is performed with the starting point P1 as a reference. Thereafter, the unwrapping process is performed in the same procedure, and when the unwrapping process for the straight line route R6 is finished, the step S11 is finished.
  • a wraparound path is set for the pixels remaining behind the NG area, and a wraparound process is performed for performing an unwrap process along the wraparound path (step S12).
  • the wraparound path WR0 is set for pixels remaining in the same row as the straight line route R1
  • the wraparound path WR1 is set for pixels remaining in the same row as the straight line route R5.
  • the wraparound path WR0 is unwrapped from the pixel on the adjacent straight path R0.
  • the wraparound path WR1 is subjected to unwrap processing starting from a pixel on the adjacent straight path R6.
  • the unwrapping process on each path sequentially detects discontinuous points DP that change from the upper limit to the lower limit of the function range of the function of the above formula (8) or the above formula (9), or from the lower limit to the upper limit.
  • the data after the detected discontinuous point DP is uniformly added or subtracted with a value corresponding to this range to eliminate the discontinuous point DP and to make the data continuous.
  • the phase differential image may be divided by the NG region, and there may be a plurality of OK regions.
  • steps S10 to S12 are individually executed for each OK area.
  • the phase differential image of FIG. 9 includes first and second OK regions.
  • the first OK region starting points P0a to P6a are set on the penetrating line along the end in the X direction, and straight paths R0a to R6a are set in the Y direction from the starting points P0a to P6a. Then, an unwrap process along each straight path R0a to R6a and an unwrap process between the start points of the respective start points P0a to P6a are performed.
  • starting points P0b to P6b are set on the penetrating line along the end in the X direction, and straight paths R0b to R6b are set in the Y direction from the starting points P0b to P6b. Then, an unwrap process along each of the straight paths R0b to R6b and an unwrap process between the start points of the start points P0b to P6b are performed.
  • the setting is appropriately performed, and the unwrap process is performed along the set wraparound path.
  • the second unwrap processing unit 44 performs the unwrap processing on the entire offset image. Specifically, as shown in FIG. 10, the second unwrap processing unit 44 sets starting points P0 to P6 along the X direction end of the offset image, and linear paths from the starting points P0 to P6 in the Y direction. R0 to R6 are set, and an unwrap process along each straight path R0 to R6 and an unwrap process between the start points of the respective start points P0 to P6 are performed. In this case, the start point (start point P0) for starting the unwrap process for the offset image and the start point (start point P0) for starting the unwrap process for the phase differential image are set to the same pixel position.
  • the second unwrap processing unit 44 determines the first starting point, the straight line route, and the wraparound route with respect to the offset image.
  • the unwrap processing is set in the same position as the starting point, straight line route, and wraparound route set by the unwrap processing unit 43, and unwrap processing is performed in the same order as the unwrap processing by the first unwrap processing unit 43.
  • step S20 When the shooting mode is selected using the operation unit 18a (step S20), it is determined whether or not the selected shooting mode is pre-shooting (step S21). If it is pre-photographing, a standby state for photographing instructions is entered (step S22).
  • step S22 When an imaging instruction is given using the operation unit 18a (YES in step S22), the X-ray source 11 X is scanned at each scanning position k while the second grating 22 is moved by a predetermined scanning pitch by the scanning mechanism 23. Radiation and detection of the G2 image by the X-ray image detector 13 are performed (step S23). As a result of the fringe scanning, M pieces of image data are generated and stored in the memory 14.
  • the image data for M sheets stored in the memory 14 is read by the image processing unit 15.
  • a phase differential image is generated by the phase differential image generation unit 40 (step S24).
  • This phase differential image is stored in the offset image storage unit 41 as an offset image (step S25).
  • the pre-photographing operation ends here. Note that this pre-imaging may be performed at least once in a state in which the subject H is not disposed when the X-ray imaging apparatus 10 is started up, and need not be performed every time before the main imaging.
  • step S30 when the subject H is arranged and the main imaging is selected by selecting the imaging mode in step S20 (NO in step S21), the imaging instruction standby state is set (step S30).
  • a photographing instruction is given using the operation unit 18a (YES in step S30)
  • the same stripe scanning as in step S23 is performed (step S31), and M pieces of image data are stored in the memory 14.
  • the phase differential image is generated by the phase differential image generation unit 40 (step S32).
  • the NG area and the OK area are detected by the OK / NG area detecting unit 42 (step S33).
  • the first unwrap processing unit 43 unwraps only the OK region of the phase differential image generated in step S32 (step S34).
  • the second unwrap processing unit 44 performs unwrap processing on the offset image stored in the offset image storage unit 41. It is determined whether or not there are a plurality of OK regions in the offset image (step S35). If there are a plurality of OK regions (YES in step S35), only the OK region of the offset image is subjected to the first unwrap process. Unwrap processing is performed in the same procedure as the unit 43 (step S36). On the other hand, if there is only one OK area in the offset image (NO in step S35), unwrap processing is performed on the entire offset image (step S37).
  • the offset correction unit 45 subtracts the offset image that has been unwrapped by the second unwrap processor 44 from the phase differential image that has been unwrapped by the first unwrap processor 43. Performed (step S38). Thereby, subtraction of the pixel value is performed in the corresponding pixel 30.
  • the phase contrast image generation unit 46 integrates the differential phase image (difference image) after the offset correction, thereby generating a phase contrast image (step S39).
  • the phase differential image and the phase contrast image after the offset correction are recorded in the image recording unit 16 and then displayed on the monitor 18b (step S40).
  • the first unwrap processing unit 43 performs the unwrap process only on the OK region other than the NG region in which the unwrap error is likely to occur in the phase differential image. Therefore, the unwrap error hardly occurs and the noise is small. A phase differential image is obtained. Since soft tissue (cartilage portion or the like), which is a region of interest in X-ray phase imaging, exists outside the NG region, it is prevented that imaging of the soft tissue is inhibited by noise due to unwrapping errors.
  • the second unwrap processing unit 44 performs unwrap processing in the same procedure (the same start point and the same processing route) as the first unwrap processing unit 43 when there are a plurality of OK regions.
  • the noise unevenness included in the phase differential image is almost the same as the noise unevenness of the offset image.
  • FIG. 13C in the differential phase image (difference image) after the offset correction, there is almost no difference in pixel value between the OK regions.
  • the same unwrap processing is performed on each OK region by the first and second unwrap processing units 43 and 44.
  • the pixel values of the OK areas of the images do not match and a difference is generated.
  • the offset correction becomes incomplete, and a slight level difference occurs in the pixel value between the OK regions in the difference image.
  • the calibration processing unit 47 calculates a difference in pixel value at the starting point (starting point P0) of the unwrap process for each OK region with respect to the phase differential image after the unwrap process and the offset image after the unwrap process.
  • the pixel values in each OK region are calibrated. Specifically, for each OK region, as shown in FIGS. 15A and 15B, a difference ⁇ of the pixel value at the starting point P0 of the offset image with respect to the pixel value at the starting point P0 of the phase differential image is obtained. As shown in FIG. 15C, the difference ⁇ is added to the pixel value in the OK area of the offset image.
  • the degree of noise unevenness in the XY plane may differ between the phase differential image after unwrapping and the offset image after unwrapping. In this case, noise having an inclination remains in the differential image after offset correction. For this reason, as shown in FIG. 16, it is preferable to further provide an inclination correction processing unit 48 in the subsequent stage of the offset processing unit 45 in the image processing unit 15.
  • the inclination correction processing unit 48 performs a two-dimensional correction representing the inclination tendency in the XY plane by fitting each OK region of the difference image after the offset correction in the X direction and the Y direction with a linear form or a polynomial.
  • the inclination is removed by generating data and subtracting the correction data from the difference image. This prevents noise from remaining in the differential image after offset correction due to the difference in the slope of the noise unevenness.
  • the second unwrap processing unit 44 performs unwrap processing on the entire offset image when there is only one OK region. However, even when there is only one OK region, only the OK region is performed. On the other hand, unwrapping processing may be performed.
  • Each of the straight paths R0 to R6 from the starting points P0 to P6 may be unwrapped.
  • the Y direction is given priority in the Y direction.
  • the starting point is set so as to be along, the starting point may be set so as to be along the X direction in preference to the X direction.
  • the setting direction of the starting point is determined so that the number of wraparound processes performed on the pixels remaining behind the NG area is reduced.
  • the wrapping process is required for two lines along the X direction (lines including the starting points P1 and P5). The number of times is two.
  • the wraparound process is required for six lines along the Y direction, and the number of wraparound processes is 6. Therefore, when the NG area has the shape shown in FIG. 7, the Y direction in which the number of wraparound processes is reduced is determined as the starting direction setting direction.
  • the starting point is set along the X-direction end or the Y-direction end in the OK region, but the starting point is not necessarily OK. It is not necessary to set along the edge in the region.
  • a starting point is set to each column or each row so that an unwrap process may be performed for every column or each row of a phase differential image.
  • one starting point may be set in the OK region, and adjacent pixels from this starting point may be unwrapped in order.
  • a start point P0 is set in the OK region, and pixels adjacent in the X direction and the Y direction from this start point P0 are unwrapped.
  • the pixels adjacent in the X and Y directions are unwrapped from each unwrapped pixel.
  • the adjacent pixel is a pixel belonging to the NG area, it is not considered and the unwrapping process is not performed.
  • the adjacent pixel is an adjacent pixel of another pixel that has been unwrapped, priority is given to one of them.
  • the adjacent pixel in the X direction has priority over the adjacent pixel in the Y direction.
  • the unwrapping process may be advanced in the same manner.
  • the OK / NG region detection unit 42 detects an NG region in which an unwrapping error is likely to occur based on the average intensity, amplitude, or visibility of the intensity modulation signal. Is not limited to this, and an area where variation between pixels of the average intensity of the intensity modulation signal (that is, dispersion between pixels of the absorption image) or dispersion between pixels of the phase differential image is larger than a predetermined value is detected as an NG area. May be.
  • variation between the pixels of this phase differential image is a dispersion
  • an absolute value is taken for each pixel of the phase differential image, and an edge portion of the superabsorbent region can be detected by detecting a portion where the absolute value exceeds a predetermined value.
  • the region may be detected as an NG region.
  • an area where the average intensity or the maximum intensity of the intensity modulation signal is larger than a predetermined value and the intensity modulation signal is saturated may be detected as an NG area.
  • This saturation of the intensity modulation signal is likely to occur in a pixel region (elementary region) that is directly transmitted to the X-ray image detector 13 through the first and second gratings 21 and 22 without passing through the subject H.
  • the intensity modulation signal is saturated, the phase shift amount ⁇ (x) cannot be obtained accurately, and this unaccompanied region is also a region where unwrapping errors are likely to occur. You may combine the above detection criteria suitably.
  • the pixel value of the predetermined pixel 30 is always high or low. May be.
  • the region where such a pixel defect occurs is a region where an unwrapping error is likely to occur because the average intensity, amplitude, or visibility of the intensity modulation signal indicates an abnormal value.
  • Such a pixel defect region can also be detected as an NG region by appropriately combining the above detection criteria.
  • an NG area image replacement unit 50 may be provided in the image processing unit 15.
  • the NG region image replacement unit 50 generates an absorption image, a differential image of the absorption image, or a small-angle scattered image based on the M image data stored in the memory 14 at the time of the main photographing, and corresponds to the NG region of the image.
  • the portion to be replaced is inserted into the NG area of the phase differential image after offset correction.
  • the NG area of the phase contrast image may be replaced.
  • the absorption image is generated by imaging the average intensity of the intensity modulation signal.
  • the differential image of the absorption image is generated by differentiating the absorption image in a predetermined direction (for example, the X direction).
  • the small angle scattered image is generated by imaging the amplitude of the intensity modulation signal.
  • the first and second unwrap processing units 43 and 44 are provided as separate processing units. However, they may be integrated into a single unwrap processing unit.
  • the unwrap processing unit executes the processing by the first unwrap processing unit 43 on the phase differential image obtained in the main imaging, and performs the processing by the second unwrap processing unit 44 on the offset image. Execute.
  • the subject H is disposed between the X-ray source 11 and the first grating 21, but the subject H is disposed between the first grating 21 and the second grating 22. You may arrange.
  • the second grating 22 is moved in the direction (X direction) perpendicular to the grid lines during fringe scanning.
  • the second grid 22 is inclined with respect to the grid lines (XY plane). May be moved in a direction not orthogonal to the X direction and the Y direction.
  • This moving direction may be any direction as long as it is within the XY plane and other than the Y direction.
  • the scanning position k may be set based on the X-direction component of the movement of the second grating 22.
  • lattice 22 is moved at the time of fringe scanning, it replaces with the 2nd grating
  • the X-ray source 11 that emits cone-beam X-rays emitted from the X-ray source 11 is used.
  • an X-ray source that emits parallel-beam X-rays is used.
  • emitted from the X-ray source 11 are made to inject into the 1st grating
  • the X focus may be dispersed by providing a multi-slit (source grating) described in WO 2006/131235 between the X-ray source 11 and the first grating 21).
  • the pitch p 0 of the multi-slit needs to satisfy the following formula (10).
  • the distance L 0 represents the distance from the multi slit to the first grating 21.
  • the position of the multi-slit becomes the position of the X-ray focal point, so the distance L 1 in the above embodiment is replaced with the distance L 0 .
  • the first and second gratings 21 are used in addition to performing the fringe scanning by moving the first grating 21 or the second grating 22 while the multi-slit is fixed. , 22 is fixed, and the multi-slit is moved to perform the fringe scanning.
  • the multi-slit may be intermittently moved in the X direction using a value (p 0 / M) obtained by dividing the multi-slit pitch p 0 by M as described above.
  • lattice 21 is comprised so that incident X-ray may be projected geometrically optically, as known in WO2004 / 058070 etc.
  • lattice 21 is comprised. May be configured to generate the Talbot effect.
  • a small-focus X-ray light source or the multi-slit may be used so as to enhance the spatial coherence of X-rays.
  • the first grating 21 can be a phase-type grating.
  • Talbot distance Z m is dependent on the beam shape of the structure and the X-ray of the first grating 21.
  • the first grating 21 are absorption type grating
  • Talbot distance Z m is represented by the following formula (11).
  • “m” is a positive integer.
  • the grating pitches p 1 and p 2 are set so as to substantially satisfy the above formula (1) (however, when a multi-slit is used, the distance L 1 is replaced with the distance L 0 ).
  • the Talbot distance Z m is And expressed by the following formula (12).
  • “m” is “0” or a positive integer.
  • the grating pitches p 1 and p 2 are set so as to substantially satisfy the above formula (1) (however, when a multi-slit is used, the distance L 1 is replaced with the distance L 0 ).
  • the Talbot distance Z m is as follows. It is represented by Formula (13). Here, “m” is “0” or a positive integer. In this case, since the pattern period of the G1 image is 1 ⁇ 2 times the grating period of the first grating 21, the grating pitches p 1 and p 2 are set so as to substantially satisfy the following expression (14). (However, when using a multi-slit, the distance L 1 is replaced by a distance L 0).
  • the first grating 21 is absorption grating, if X-rays emitted from the X-ray source 11 is a parallel beam shape, Talbot distance Z m is represented by the following formula (15).
  • “m” is a positive integer.
  • the Talbot distance Z m is It is represented by the following formula (16).
  • “m” is “0” or a positive integer.
  • the Talbot distance Z m is It is represented by Formula (17).
  • “m” is “0” or a positive integer.
  • the grating portion 12 is provided with the two gratings of the first and second gratings 21 and 22.
  • the second grating 22 may be omitted and only the first grating 21 may be used. Is possible.
  • the second grating 22 can be omitted and only the first grating 21 can be provided.
  • This X-ray image detector is a direct conversion type X-ray image detector including a conversion layer that converts X-rays into electric charges and a charge collection electrode that collects electric charges converted in the conversion layer.
  • the charge collection electrode includes a plurality of linear electrode groups.
  • One linear electrode group is obtained by electrically connecting linear electrodes arranged at a constant period, and is arranged so that the phases thereof are different from those of other linear electrode groups.
  • This linear electrode group functions as the second grating 22, and the presence of a plurality of linear electrode groups allows detection of a plurality of G2 images having different phases in one imaging. Therefore, in this configuration, the scanning mechanism 23 can be omitted.
  • the single image data obtained by the X-ray image detector 13 is divided into groups of pixel rows (pixels arranged in the X direction) having different phases from each other with respect to the moire fringes, and a plurality of divided image data is obtained.
  • a phase differential image is generated in the same procedure as the above-described fringe scanning method, assuming that the images are based on a plurality of different G2 images by fringe scanning.
  • the intensity modulation signal described above is expressed as a change in intensity of pixel values for one cycle of moire fringes generated in single image data.
  • the scanning mechanism 23 is omitted, and the phase differential image is obtained based on the single image data obtained by the X-ray image detector 13 via the first and second gratings 21 and 22.
  • a Fourier transform method described in WO2010 / 050484 is known. This Fourier transform method obtains a Fourier spectrum by performing a Fourier transform on the single image data, separates a spectrum corresponding to a carrier frequency (a spectrum carrying phase information) from the Fourier spectrum, and then reverses the spectrum.
  • This is a method of generating a phase differential image by performing Fourier transform.
  • the intensity modulation signal described above is expressed as a change in intensity of pixel values for one cycle of moire fringes generated in a single image data, as in the case of the pixel division method.
  • the present invention can be applied to an industrial radiography apparatus and the like in addition to a radiography apparatus for medical diagnosis.
  • a radiography apparatus for medical diagnosis In addition to X-rays, gamma rays or the like can be used as radiation.

Abstract

L'objectif de la présente invention est de réduire les erreurs de déroulement et d'améliorer l'annulation du décalage. Un détecteur d'image à rayons X (13) détecte les rayons X qui sont émis par une source de rayons X (11) et qui traversent un sujet (H), un premier réseau (21) et un deuxième réseau (22), et produit des données d'image. Une section de production d'image différentielle de phase (40) produit une image différentielle de phase sur la base des données d'image. Un détecteur de régions appropriées/inappropriées (42) détecte des régions inappropriées dans lesquelles des erreurs de déroulement ont tendance à se produire dans l'image différentielle de phase, et définit les autres régions comme étant des régions appropriées. Une première section de déroulement (43) ne déroule que les régions appropriées de l'image différentielle de phase. Une deuxième section de déroulement (44) déroule l'image différentielle de phase (image décalée) obtenue par la section de production d'image différentielle de phase (40) sans retirer le sujet. Une section de traitement du décalage (45) soustrait l'image décalée déroulée de l'image différentielle de phase déroulée.
PCT/JP2012/069136 2011-08-22 2012-07-27 Dispositif de radiographie et procédé de radiographie WO2013027536A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2011180535A JP2014217398A (ja) 2011-08-22 2011-08-22 放射線撮影装置及び放射線撮影方法
JP2011-180535 2011-08-22

Publications (1)

Publication Number Publication Date
WO2013027536A1 true WO2013027536A1 (fr) 2013-02-28

Family

ID=47746287

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2012/069136 WO2013027536A1 (fr) 2011-08-22 2012-07-27 Dispositif de radiographie et procédé de radiographie

Country Status (2)

Country Link
JP (1) JP2014217398A (fr)
WO (1) WO2013027536A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111343921A (zh) * 2017-12-26 2020-06-26 株式会社岛津制作所 X射线摄影装置

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2020072912A (ja) * 2019-11-06 2020-05-14 株式会社三共 遊技機

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004058070A1 (fr) * 2002-12-26 2004-07-15 Atsushi Momose Systeme d'imagerie a rayons x et procede d'imagerie associe
JP2005152500A (ja) * 2003-11-28 2005-06-16 Hitachi Ltd Ｘ線撮像装置及び撮像方法
JP2008082869A (ja) * 2006-09-27 2008-04-10 Mitsutoyo Corp 干渉縞解析における位相接続方法
JP2011045655A (ja) * 2009-08-28 2011-03-10 Konica Minolta Medical & Graphic Inc Ｘ線撮影装置

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2004058070A1 (fr) * 2002-12-26 2004-07-15 Atsushi Momose Systeme d'imagerie a rayons x et procede d'imagerie associe
JP2005152500A (ja) * 2003-11-28 2005-06-16 Hitachi Ltd Ｘ線撮像装置及び撮像方法
JP2008082869A (ja) * 2006-09-27 2008-04-10 Mitsutoyo Corp 干渉縞解析における位相接続方法
JP2011045655A (ja) * 2009-08-28 2011-03-10 Konica Minolta Medical & Graphic Inc Ｘ線撮影装置

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
SHIGESUMI KUWASHIMA: "Jitsujikan Sanjigen Gazo Keisoku (Tokushu Hikari Sanjigen Keisoku Gijutsu no Genjo to Shorai Doko)", OPTICAL AND ELECTRO-OPTICAL ENGINEERING CONTACT, vol. 39, no. 2, February 2001 (2001-02-01), pages 92 - 102 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111343921A (zh) * 2017-12-26 2020-06-26 株式会社岛津制作所 X射线摄影装置
CN111343921B (zh) * 2017-12-26 2023-03-14 株式会社岛津制作所 X射线摄影装置

Also Published As

Publication number Publication date
JP2014217398A (ja) 2014-11-20

Similar Documents

Publication Publication Date Title
JP5475737B2 (ja) 放射線撮影装置及び画像処理方法
JP5731214B2 (ja) 放射線撮影システム及びその画像処理方法
JP5378335B2 (ja) 放射線撮影システム
JP5438649B2 (ja) 放射線撮影システム及び位置ずれ判定方法
JP2012090944A (ja) 放射線撮影システム及び放射線撮影方法
JP2011218147A (ja) 放射線撮影システム
JP2011224329A (ja) 放射線撮影システム及び方法
JP2012090945A (ja) 放射線検出装置、放射線撮影装置、放射線撮影システム
JP2011224330A (ja) 放射線撮影システム及びそのオフセット補正方法
WO2013065502A1 (fr) Procédé et dispositif d'imagerie radiographique
WO2012057022A1 (fr) Système et procédé de radiographie
JP2011206490A (ja) 放射線撮影システム及び放射線撮影方法
JP2014138625A (ja) 放射線撮影装置及び画像処理方法
WO2013027536A1 (fr) Dispositif de radiographie et procédé de radiographie
WO2013038881A1 (fr) Dispositif de radiographie et procédé de traitement d'image
WO2013027519A1 (fr) Dispositif de radiographie et procédé de déroulement
JP2013042788A (ja) 放射線撮影装置及びアンラップ処理方法
JP5635169B2 (ja) 放射線撮影システム
WO2013099467A1 (fr) Procédé et appareil de radiographie
JP5610480B2 (ja) 放射線画像処理装置及び方法
JP2011206162A (ja) 放射線撮影システム及び方法
JP2013063098A (ja) 放射線撮影装置及び画像処理方法
JP2012228301A (ja) 放射線撮影装置
WO2012057023A1 (fr) Système d'imagerie radiographique et procédé de commande de celui-ci
JP2012228361A (ja) 放射線撮影装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12826400

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12826400

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP