WO2012053368A1 - Grid for radiation imaging, method for manufacturing same, and radiation imaging system - Google Patents

Grid for radiation imaging, method for manufacturing same, and radiation imaging system Download PDF

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Publication number
WO2012053368A1
WO2012053368A1 PCT/JP2011/073066 JP2011073066W WO2012053368A1 WO 2012053368 A1 WO2012053368 A1 WO 2012053368A1 JP 2011073066 W JP2011073066 W JP 2011073066W WO 2012053368 A1 WO2012053368 A1 WO 2012053368A1
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WIPO (PCT)
Prior art keywords
grid
support
radiation
ray
substrate
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PCT/JP2011/073066
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French (fr)
Japanese (ja)
Inventor
金子　泰久
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富士フイルム株式会社
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Publication of WO2012053368A1 publication Critical patent/WO2012053368A1/en

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    • 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
    • A61B6/06—Diaphragms
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21K—TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
    • G21K1/00—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating
    • G21K1/06—Arrangements for handling particles or ionising radiation, e.g. focusing or moderating using diffraction, refraction or reflection, e.g. monochromators
    • 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
    • A61B6/40—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment with arrangements for generating radiation specially adapted for radiation diagnosis
    • A61B6/4035—Apparatus for radiation diagnosis, e.g. combined with radiation therapy equipment with arrangements for generating radiation specially adapted for radiation diagnosis the source being combined with a filter or grating
    • 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
    • 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

Definitions

  • the present invention relates to a grid used for radiographic imaging, a method for manufacturing the grid, and a radiographic imaging system using the grid.
  • phase imaging is used to obtain a high-contrast image (hereinafter referred to as a phase contrast image) from a subject having a low X-ray absorption capacity based on the phase change of the X-ray by the subject.
  • An X-ray imaging system using the Talbot interference effect is known as a kind of X-ray phase imaging (see, for example, Patent Document 1 and Non-Patent Document 1).
  • the first grid is disposed behind the subject as viewed from the X-ray source, and the second grid is disposed downstream from the first grid by the Talbot distance.
  • An X-ray image detector that detects an X-ray and generates an image is disposed behind the second grid.
  • the first grid and the second grid are striped grids in which X-ray absorbing portions and X-ray transmitting portions extended in one direction are alternately arranged along an arrangement direction orthogonal to the extension direction.
  • the Talbot distance is the distance at which X-rays that have passed through the first grid form a self-image (stripe image) due to the Talbot interference effect.
  • a phase contrast image is acquired based on a change in a striped image intensity-modulated by superimposing the self-image of the first grid and the second grid depending on the subject.
  • This is called a fringe scanning method.
  • the second grid is intermittently moved with respect to the first grid, and photographing is performed while the second grid is stopped. This intermittent movement is performed at a constant scanning pitch obtained by equally dividing the grid pitch in a direction substantially parallel to the plane of the first grid and substantially perpendicular to the grid direction of the first grid.
  • a phase differential image representing the distribution of the X-ray refraction angle in the subject is obtained.
  • a phase contrast image is obtained from this phase differential image.
  • This fringe scanning method is also used in an imaging apparatus using laser light (see, for example, Non-Patent Document 2).
  • the first and second grids have a fine structure in which X-ray absorbers are arranged at a pitch of several ⁇ m.
  • This X-ray absorption part is required to have high X-ray absorption.
  • the X-ray absorption part of the second grid needs higher X-ray absorption than the X-ray absorption part of the first grid in order to surely modulate the intensity of the fringe image.
  • the X-ray absorption parts of the first and second grids are made of heavy atomic weight gold (Au).
  • the X-ray absorption part of the second grid needs to have a relatively large thickness with respect to the X-ray traveling direction and have a high aspect ratio (a value obtained by dividing the thickness of the part that absorbs X-rays by the width). It is.
  • a silicon semiconductor process cannot manufacture a grid having a large area larger than the size of the wafer because the area of the grid to be manufactured is limited to the size of the wafer.
  • phase imaging since the imaging range is limited to the size of the first and second grids, it is desired to increase the area of the grid.
  • small grids is formed by arranging a plurality of small-area grids (hereinafter referred to as small grids) (see, for example, Patent Documents 1 and 2).
  • Patent Document 1 discloses that vignetting is reduced by arranging a plurality of small grids on a concave surface to form a large-area grid.
  • Patent Document 2 discloses that a plurality of small grids are arranged on a concave surface to form a large-area grid having a converging structure, and further the small grids are curved.
  • An object of the present invention is to obtain a large-area grid having a converging structure without bending the grid portion.
  • the grid for radiographic imaging of the present invention includes a plurality of plate-like grid portions in which radiation absorbing portions and radiation transmitting portions are alternately arranged, and each of the above-mentioned respective so as to face the focal point of the radiation source. And a support portion that supports the grid portion in a state where the grid portion is inclined at a predetermined angle.
  • the support part has a plurality of support tables individually provided for each grid part. Moreover, it is preferable that each said support stand inclines the said grid part at an angle according to the position on the said support substrate.
  • each of the support bases is a base substrate at the time of manufacturing the grid portion, and preferably has radiation transparency.
  • each said support stand is joined to the surface on the opposite side to the radiation-incidence side of the said grid part, and has a radiation transmittance.
  • the support portion has a plurality of inclined surfaces having different inclination angles, and the grid portions are respectively joined to the inclined surfaces.
  • the method for manufacturing a radiographic imaging grid includes a grid portion forming step of forming a flat grid portion in which radiation absorbing portions and radiation transmitting portions are alternately arranged, and the grid portion is inclined at a predetermined angle.
  • the support table forming step includes a base material holding step for holding the grid portion and the base substrate as the support table in a state inclined at a predetermined angle, and a polishing surface parallel to the surface of the support substrate. It is preferable to include a polishing step of forming a bonding surface with the support substrate by polishing the base substrate with a polishing apparatus.
  • the support table forming step includes a base material holding step for holding a base material having radiation transparency in a state inclined at a predetermined angle, and a polishing apparatus having a polishing surface parallel to the surface of the support substrate.
  • the radiographic imaging system of the present invention includes a first grid that generates a fringe image by passing radiation emitted from a radiation source, a second grid that applies intensity modulation to the fringe image, and the second grid.
  • a radiographic image detector for detecting a fringe image intensity-modulated by the radiographic image detector, and generating a phase contrast image from the fringe image detected by the radiographic image detector.
  • At least one of the grids is supported in a state where each of the grid portions is inclined at a predetermined angle so as to face the focal point of the radiation source and a plurality of flat grid portions in which radiation absorbing portions and radiation transmitting portions are alternately arranged. And a supporting part.
  • a third grid disposed between the radiation source and the first grid and configured to selectively shield the radiation emitted from the radiation source to form a plurality of line-shaped radiation;
  • the third grid supports the plurality of flat grid portions in which the radiation absorption portions and the radiation transmission portions are alternately arranged, and the respective grid portions inclined at a predetermined angle so as to face the focal point of the radiation source. And a support part.
  • each grid part is supported by the support part so that it may face a radiation focus, it can comprise the grid of a convergence structure, although it is flat form.
  • FIG. 1 is a perspective view showing a configuration of an X-ray image capturing system. It is a top view of the 2nd grid.
  • FIG. 2B is a cross-sectional view taken along the line IIB-IIB in FIG. 2A. It is sectional drawing which shows the Y direction cross section of a small grid. It is sectional drawing which shows the manufacture procedure 1 of a small grid. It is sectional drawing which shows the manufacturing procedure 2 of a small grid. It is sectional drawing which shows the manufacturing procedure 3 of a small grid. It is sectional drawing which shows the manufacture procedure 4 of a small grid. It is explanatory drawing explaining the grinding
  • an X-ray imaging system 10 includes an X-ray source 11, a source grid 12, a first grid 13, and a second grid arranged along the Z direction that is an X-ray irradiation direction. 14 and an X-ray image detector 15.
  • the X-ray source 11 has a rotary anode type X-ray tube (not shown) and a collimator (not shown) for limiting the X-ray irradiation field, and the subject H is irradiated with X-rays. Radiate.
  • the radiation source grid 12, the first grid 13, and the second grid 14 are absorption grids that absorb X-rays, and are disposed to face the X-ray source 11 in the Z direction. Between the radiation source grid 12 and the first grid 13, an interval at which the subject H can be arranged is provided. The distance between the first grid 13 and the second grid 14 is not more than the minimum Talbot distance.
  • the X-ray image detector 15 is a flat panel detector using a semiconductor circuit, and is disposed behind the second grid 14.
  • the second grid 14 is composed of five small grids 17 to 21 and a support substrate 23 to which the small grids 17 to 21 are bonded via an adhesive 22.
  • the support substrate 23 is made of a material having high X-ray transparency, such as glass, carbon, and acrylic.
  • the adhesive 22 is an organic adhesive having X-ray transparency.
  • a gap between adjacent small grids is filled with a material having X-ray absorption.
  • Each small grid 17 to 21 has an elongated rectangular shape extending in the X direction.
  • the small grids 17 to 21 are arranged in the Y direction on the support substrate 23.
  • the small grids 17 to 21 are inclined at different angles so as to face the X-ray focal point 11a of the X-ray source 11.
  • the second grid 14 has a converging structure corresponding to cone-beam X-rays, X-ray vignetting is small.
  • at least two small grids are required.
  • the number of small grids is preferably as large as possible.
  • the small grids 17 to 21 include grid portions 17a to 21a and base substrates 17b to 21b.
  • the base substrates 17b to 21b constitute a support portion that supports the grid portions 17a to 21a in an inclined state so as to face the X-ray focal point of the X-ray source 11.
  • the grid part 17 a includes an X-ray absorption part 25 and an X-ray transmission part 26.
  • the X-ray absorption part 25 and the X-ray transmission part 26 are extended substantially in the X direction and are alternately arranged along the Y direction substantially orthogonal to the X direction.
  • the X-ray absorption part 25 is formed of a material having X-ray absorption such as gold or platinum.
  • the X-ray transmission part 26 is made of a material having X-ray transmission properties such as silicon.
  • the width W2 and the pitch P2 of the X-ray absorber 25 are the distance between the source grid 12 and the first grid 13, the distance between the first grid 13 and the second grid 14, and the first It is determined by the pitch of the X-ray absorption part of the grid 13 or the like.
  • the width W2 is about 2 to 20 ⁇ m.
  • the pitch P2 is about 4 to 40 ⁇ m.
  • the thickness T2 in the Z direction of the X-ray absorber 25 is preferably as thick as possible in order to obtain high X-ray absorption, but considering the vignetting of cone-beam X-rays emitted from the X-ray source 11.
  • the thickness is preferably about 100 ⁇ m.
  • the width W2 is 2.5 ⁇ m
  • the pitch P2 is 5 ⁇ m
  • the thickness T2 is 100 ⁇ m.
  • the other grid parts 18a, 19a, 20a, and 21a are the structures similar to the grid part 17a, detailed description is abbreviate
  • the base substrates 17b to 21b are reinforcing substrates joined to the lower surfaces of the grid portions 17a to 21a, and are formed of a material having high X-ray transmissivity such as glass, carbon, and acrylic.
  • the base substrates 17 b to 21 b have bonding surfaces 17 c to 21 c that are bonded to the support substrate 23.
  • the joint surfaces 17c to 21c are inclined at a predetermined angle so that the grid portions 17a to 21a face the X-ray focal point 11a.
  • the base substrates 17 b and 21 b of the small grids 17 and 21 at the outer edge portion having the largest inclination angle are small in the height of the small grids 17 and 21. It is formed thin so as to be approximately the same as the height of ⁇ 20.
  • the source grid 12 and the first grid 13 are composed of a plurality of small grids and a support substrate in which the small grids are bonded together with an adhesive, like the second grid 14. Further, the small grids of the source grid 12 and the first grid 13 are provided with a grid portion and a base substrate as in the case of the second grid 14.
  • the grid portion includes X-ray absorption portions and X-ray transmission portions that are extended in the X direction and alternately arranged along the Y direction orthogonal to the X direction. Since the X-ray absorption part and the X-ray transmission part have substantially the same configuration as the second grid 13 except that the width and pitch in the Y direction, the thickness in the Z direction, and the like are different, detailed description thereof is omitted.
  • the base substrate 17b is bonded to the lower surface of the X-ray transparent substrate 27 formed of silicon or the like.
  • a conductive seed layer 28 is provided on the surface of the base substrate 17b bonded to the X-ray transparent substrate 27.
  • a metal film such as Au or Ni, or a metal film such as Al, Ti, Cr, Cu, Ag, Ta, W, Pb, Pd, and Pt, or an alloy thereof is used.
  • the seed layer 28 is not limited to the base substrate 17b, but may be provided on the X-ray transparent substrate 27, or may be provided on both the X-ray transparent substrate 27 and the base substrate 17b.
  • an etching mask 30 is formed on the X-ray transmissive substrate 27 by using a general photolithography technique.
  • the etching mask 30 has a striped pattern that extends linearly in the X direction and is periodically arranged at a predetermined pitch in the Y direction.
  • a plurality of grooves 32 and a plurality of X-ray transmission portions 26 are formed in the X-ray transmission substrate 27.
  • the groove 32 requires a high aspect ratio with a width of several ⁇ m and a depth of about 100 ⁇ m. For this reason, for the dry etching for forming the grooves 32, deep etching such as a Bosch process or a cryo process is used.
  • the groove may be formed by forming the X-ray transparent substrate 27 using a photosensitive resist instead of silicon and exposing it with synchrotron radiation.
  • the groove 32 is filled with an X-ray absorbing material such as gold by electrolytic plating, and the X-ray absorbing portion 25 is formed.
  • the X-ray transparent substrate 27 is immersed in the plating solution with the current terminal connected to the sheath layer 28 while being held on the base substrate 17b.
  • the other electrode anode
  • the other electrode is prepared at a position facing the X-ray transparent substrate 27, and a current flows between the current terminal and the anode.
  • metal ions in the plating solution on the patterned X-ray transparent substrate 27 gold is embedded in the grooves 32. Thereafter, the etching mask 30 is removed using an ashing method or the like.
  • the filling method of the X-ray absorber in the groove 32 is not limited to the electrolytic plating method, and for example, the X-ray absorber may be filled as a paste or a colloid. In this case, the seeds layer 28 is unnecessary.
  • the lower portion of the base substrate 17b is cut obliquely to form an inclined bonding surface 17c.
  • the small grid 17 is held by a polishing holder 34 that sucks the grid portion 17a by air suction.
  • a suction surface 34a for suction is inclined at a predetermined angle.
  • the polishing holder 34 is moved above the polishing plate 35 of the polishing apparatus 36 by a moving mechanism (not shown).
  • the base substrate 17 b is pressed against the polishing plate 35 that is rotationally driven when the polishing holder 34 is lowered toward the polishing device 36.
  • the lower surface of the base substrate 17b is polished by the polishing plate 35, whereby the bonding surface 17c is formed.
  • alignment marks 38 are provided at two corners of the bonding surface 17c of the base substrate 17b.
  • the alignment mark 38 is provided at a predetermined position related to the grid pattern of the grid portion 17a. The recognition of the grid pattern is performed based on, for example, an image obtained by photographing with an imaging device (not shown).
  • the alignment mark 38 may be formed by cutting a groove in the base substrate 17b, or may be formed on the bonding surface 17c using a material having X-ray transparency.
  • the thickness of the alignment mark 38 is about 0.01 to 1 ⁇ m so as not to hinder the bonding to the support substrate 23. Is preferred.
  • the small grid 17 is bonded to the support substrate 23.
  • the small grid 17 is held by a bonding holder 40 that sucks the grid portion 17a by air suction.
  • the suction surface 40a that performs suction is inclined according to the angle of the joint surface 17c. Accordingly, the small grid 17 is held in a state where the joint surface 17c is horizontal.
  • the joining holder 40 is moved above the support substrate 23 coated with the adhesive 22 by a moving mechanism (not shown).
  • a pair of alignment marks 42 corresponding to the alignment marks 38 of the small grid 17 are provided on the upper surface of the support substrate 23.
  • Two position detection units 45 are inserted between the small grid 17 and the support substrate 23.
  • the position detection unit 45 is composed of a pair of alignment cameras 43 and 44 arranged back to back so that the upper and lower parts can be photographed simultaneously, and the alignment marks 38 and 42 are photographed by the respective cameras 43 and 44.
  • the Images taken by the alignment cameras 43 and 44 are processed by an image processing device (not shown), and the amount of positional deviation between the alignment mark 38 and the alignment mark 42 is detected.
  • the moving mechanism of the bonding holder 40 moves the small grid 17 based on the detected positional deviation amount, and performs position adjustment.
  • the adhesive 22 is preferably one that has X-ray transparency and does not undergo deformation such as shrinkage when solidified.
  • a thermosetting adhesive or an instantaneous adhesive is used.
  • the small grids 18 to 21 are manufactured in the same manner as the small grid 17 and are bonded to the support substrate 23 in the same manner, detailed description is omitted.
  • the small grid 19 attached to the center of the support substrate 23 does not need to incline the grid part 19a, the grinding
  • the source grid 12 and the first grid 13 are manufactured in the same manner as the second grid 14, a detailed description thereof is omitted.
  • X-rays radiated from the X-ray source 11 are partially shielded by the X-ray absorption part of the source grid 12, thereby reducing the effective focal size in the Y direction, and arranging many in the Y direction.
  • a line-shaped X-ray is formed.
  • the phase of each line-shaped X-ray changes when passing through the subject H.
  • a fringe image reflecting the transmission phase information of the subject H determined from the refractive index of the subject H and the transmitted optical path length is formed.
  • the fringe image generated by each line-shaped X-ray is projected onto the second grid 14 and overlaps at the position of the second grid 14.
  • the stripe image is intensity-modulated by being partially shielded by the second grid 14.
  • the second grid 14 is intermittently moved with respect to the first grid 13 using a fringe scanning method, and X-rays are irradiated from the X-ray source 11 to the subject H during the stop.
  • the X-ray image detector 15 takes an image. This intermittent movement is performed in the Y direction at a constant scanning pitch obtained by equally dividing the lattice pitch (for example, five divisions).
  • phase differentiation An image is obtained.
  • the phase differential image corresponds to the distribution of the X-ray refraction angle in the subject H.
  • the radiation source grid 12, the first grid 13, and the second grid 14 are each configured by a plurality of small grids to increase the area. For this reason, an imaging area expands rather than the case where each of the source grid 12, the first grid 13, and the second grid 14 is configured by one grid formed using a semiconductor process. Moreover, since the source grid 12, the first grid 13, and the second grid 14 are configured by a plurality of small grids that are inclined at different angles so as to face the X-ray focal point 11a, the thickness thereof as a whole is increased. A thin convergence structure is obtained. Thereby, the vignetting of the X-rays at the periphery of the grid is reduced, and a high-quality phase contrast image is obtained.
  • the small grids 17 to 21 are held by the polishing holder 34 and the bonding holder 40 for polishing and bonding. For this reason, it is necessary to prepare a plurality of types of polishing holders 34 and bonding holders 40 having suction surfaces inclined in accordance with the inclination angles of the bonding surfaces 17c to 21c of the base substrates 17b to 21b, which is inefficient. is there. Further, since the polishing holder 34 and the joining holder 40 must be exchanged in accordance with each of the small grids 17 to 21, the throughput during manufacturing is low.
  • the horizontal member 50 is attached as an adapter to the upper surface of the grid portion 17a of the small grid 17.
  • the horizontal member 50 has a lower surface inclined in accordance with the angle of the bonding surface formed on the base substrate 17b. According to the present embodiment, when the base substrate 17b is polished to form the bonding surface, the horizontal member 50 is sucked by the one type of polishing holder 51 having the horizontal suction surface 51a to hold the small grid 17. Therefore, it is not necessary to prepare a plurality of types of polishing holders.
  • the horizontal member 50 when joining the small grid 17 to the support substrate 23 after polishing the base substrate 17b, one kind of joining having a horizontal suction surface 53a. Since the horizontal member 50 can be adsorbed by the holder 53 and the small grid 17 can be held, it is not necessary to facilitate a plurality of types of joining holders.
  • the horizontal member 50 is preferably removed from the grid portion 17a after the small grid 17 is joined to the support substrate 23. However, when the horizontal member 50 is formed of an X-ray transmissive material, the grid member 17a is not changed as it is after the joining. It may be left.
  • the base substrate 17b which is the base at the time of manufacturing the grid portion 17a, is used as the support portion of the final small grid 17, but the base substrate 17b is removed and separated from the grid portion 17a. It is good also considering the formed support stand as a support part.
  • a method of manufacturing the grid according to the third embodiment will be described.
  • a base material 60 which is a material for the support base is held by a polishing holder 61 and polished by a polishing apparatus 36.
  • the polishing holder 61 has a suction surface 61a inclined at a predetermined angle, and holds and holds the substrate 60 by the suction surface 61a.
  • the base material 60 is made of a material having high X-ray permeability such as glass, carbon, and acrylic.
  • a support base 62 having a joint surface 62a is formed.
  • the support base 62 is sucked and held by a fixed stage 63 having a suction surface 63a inclined in accordance with the joining surface 62a. Thereby, the support surface 62b which supports the grid part 17a of the support stand 62 is kept horizontal.
  • An adhesive 64 is applied to the support surface 62b.
  • the adhesive 64 is an organic adhesive that has X-ray transparency and does not deform when solidified.
  • the grid portion 17a is formed by the same manufacturing method as in the first embodiment.
  • the grid portion 17 a is held by an assembly holder 65 having a horizontal suction surface 65 a and is joined to the support surface 62 b of the support base 62 via an adhesive 64.
  • the small grid 66 (refer FIG. 12) comprised by the grid part 17a and the support stand 62 is completed.
  • an alignment mark is formed on the joint surface 62a of the support base 62 as in the first embodiment.
  • the small grid 66 is held by a joining holder 67 having a suction surface 67a inclined in accordance with the joining surface 62a, as in the first embodiment.
  • the position of the bonding surface 62 a is adjusted using the alignment mark while being kept horizontal, and is bonded to the support substrate 23 via the adhesive 22.
  • the grid portions 18a to 21a are also bonded to the support substrate 23 using the support base in the same manner as the grid portion 17a.
  • the support base 62 when using resin materials, such as an acryl, as a base material of the support stand 62, you may shape
  • resin materials such as an acryl
  • polishing when the support base 62 is formed of a resin material, the alignment mark may be formed at the same time. According to this, since the polishing process of the support base 62 and the alignment mark forming process can be omitted, the throughput during manufacturing is improved.
  • the horizontal member 68 as an adapter is affixed to the grid part 17a of the small grid 66 of this 3rd Embodiment similarly to 2nd Embodiment, and this horizontal member 68 is made into horizontal It may be held by the bonding holder 69 having the suction surface 69 a and bonded to the support substrate 23.
  • the horizontal member 68 may be removed after the small grid 66 is bonded to the support substrate 23, or may be left as it is when formed of an X-ray transparent material.
  • the support base 62 is formed by polishing the base material 60.
  • flat angle members 75a and 75b having different widths are connected to the grid portion 17a and the ends.
  • the support base 76 for inclining the grid portion 17a may be formed by aligning and laminating the portions.
  • the grid portion 17a is a phase-type grid, it is preferable to place an angle member 77 outside the grid portion 17a as shown in FIG. 14B in order to prevent X-ray diffraction by the angle member.
  • the small grids 17 to 21 are arranged in the Y direction to form a grid having a concave convergence structure.
  • the small grids are arranged in a matrix to form a grid having a spherical convergence structure. It is also possible to do.
  • the second grid 80 includes small grids 81a to 81y having a cross-shaped grid pattern arranged in a matrix on the XY plane of the support substrate 82, and each of the small grids 81a to 81y is X by a base substrate. It is inclined to face the line focal point 11a.
  • the support part is comprised by providing the support stand of the small grid 17 for every small grid 17, these support stands may be integrated and a support part may be comprised.
  • the second grid 90 includes a support base 91 formed integrally with a resin material such as acrylic.
  • the support base 91 has inclined surfaces 90 a to 90 e that are inclined so as to face the X-ray focal point 11 a of the X-ray source 11.
  • the grid portions 17a to 21a of the first embodiment are joined to the inclined surfaces 90a to 90e, respectively.
  • the integral support base 91 since the integral support base 91 is used, a joining step for joining a plurality of small grids to the support substrate is unnecessary, and the manufacturing is easy. Further, since the inclined surfaces 90a to 90e are flat, deformation and cracking due to stress do not occur when the grid portions 17a to 21a are joined.
  • the support base 91 since the inclined surfaces 90a to 90e are formed along a concave shape centered on the X-ray focal point 11a, the support base 91 has a thicker outer peripheral portion than the central portion. For this reason, a difference in thermal expansion occurs between the central portion and the outer peripheral portion of the support base 91, and it is expected that the inclination angles of the inclined surfaces 90a to 90e change due to the deformation of the support base 91.
  • the inclined surfaces 93a to 93e are formed on the support base 93 of the second grid 92 by shifting their positions in the Z direction. Thereby, the thickness to the Z direction of the support stand 93 is averaged.
  • the inclined surfaces 93a to 93e are inclined so as to face the X-ray focal point 11a of the X-ray source 11, and the grid portions 17a to 21a of the first embodiment are joined to each other. .
  • the thickness of the support base 93 is averaged in the Z direction, there is little difference in thermal expansion between the central portion and the outer peripheral portion, and it is difficult to deform. Thereby, the inclination angles of the inclined surfaces 93a to 93e can be kept substantially constant.
  • the overall thickness of the second grid 92 in the Z direction can be made thinner than that of the second grid 90 of the fifth embodiment.
  • the thickness of the support base 95 of the second grid 94 is substantially uniform.
  • the inclined surfaces 95a to 95e are inclined so as to face the X-ray focal point 11a of the X-ray source 11, and the grid portions 17a to 21a of the first embodiment are joined to each other. .
  • the amount of X-ray radiated from the X-ray focal point 11a through the support table 95 is substantially uniform.
  • the configuration of the support table 95 is suitable when the first grid is a phase-type grid as will be described later. Since it is difficult for a phase difference to occur on the support base of the first grid, a high-quality self-image can be obtained by the Talbot interference effect.
  • the first and second grids are configured so as to linearly (geometrically optically) project the X-rays that have passed through the X-ray transmission part, but International Publication No. WO 2004/058070.
  • the Talbot interference effect may be generated by diffracting X-rays at the X-ray transmission part.
  • the first grid can be a phase grid instead of the absorption grid.
  • the phase type grid forms a fringe image (self-image) generated by the Talbot interference effect at the position of the second grid.
  • the subject H is disposed between the X-ray source and the first grid.
  • the subject H may be disposed between the first grid and the second grid. Good.
  • a phase contrast image is similarly generated.
  • the radiation source grid is provided, but the radiation source grid may be omitted.
  • a striped one-dimensional grid having X-ray absorbing portions and X-ray transmitting portions that are extended in one direction and alternately arranged along the arrangement direction orthogonal to the extending direction will be described as an example.
  • the present invention can also be applied to a two-dimensional grid in which the X-ray absorption part and the X-ray transmission part are arranged in two orthogonal directions.
  • the phase contrast image may be generated by a fringe scanning method in which a plurality of shootings are performed, or the phase contrast image may be generated by a single shooting.
  • phase contrast image In order to generate a phase contrast image by one shooting, for example, a checkered phase type grid is used for the first grid and a net type amplitude type grid is used for the second grid. .
  • This single photographed image is subjected to Fourier transform, and the primary spectra in the vertical and horizontal directions are respectively extracted. By performing inverse Fourier transform on these primary spectra, a phase differential image in two directions is obtained.
  • the above embodiments may be combined with each other within a consistent range.
  • the present invention is applicable not only to a radiographic imaging system for medical diagnosis but also to other radiographic systems for industrial use and nondestructive inspection.
  • the grid of the present invention can also be applied to a scattered radiation removal grid that removes scattered radiation in X-ray imaging.
  • the present invention can also be applied to a radiographic imaging system that uses gamma rays or the like in addition to X-rays.

Abstract

A large-area grid having a convergence structure is provided without bending a grid portion. A radiography system performs x-ray phase imaging. The radiography system has a first grid, a second grid and an x-ray source grid. Each of the grids is configured of a supporting substrate and a plurality of small grids (17-21) bonded to the supporting substrate. The small grids (17-21) are respectively provided with: a plurality of flat-board-like grid sections (17a-21a), each of which has x-ray absorbing portions and x-ray transmitting portions alternately disposed; and supporting tables (17b-21b), which support the grid sections (17a-21a) in a state wherein the grid sections are tilted at a predetermined angle such that the grid sections face the x-ray focal point (11a) of the x-ray source.

Description

放射線画像撮影用グリッド及びその製造方法、並びに放射線画像撮影システムRadiation imaging grid, manufacturing method thereof, and radiation imaging system
　本発明は、放射線画像の撮影に用いられるグリッド及びその製造方法と、このグリッドを用いた放射線画像撮影システムとに関する。 The present invention relates to a grid used for radiographic imaging, a method for manufacturing the grid, and a radiographic imaging system using the grid.
　放射線、例えばＸ線は、物体との相互作用により強度と位相とが変化し、位相変化が強度の変化よりも高い相互作用を示すことが知られている。このＸ線の性質を利用し、被検体によるＸ線の位相変化に基づいて、Ｘ線吸収能が低い被検体から高コントラストの画像（以下、位相コントラスト画像と称する）を得るＸ線位相イメージングの研究が着目されている。 It is known that radiation, for example, X-rays, changes in intensity and phase due to interaction with an object, and the phase change exhibits an interaction higher than the change in intensity. Using this X-ray property, X-ray phase imaging is used to obtain a high-contrast image (hereinafter referred to as a phase contrast image) from a subject having a low X-ray absorption capacity based on the phase change of the X-ray by the subject. Research has drawn attention.
　Ｘ線位相イメージングの一種として、タルボ干渉効果を用いたＸ線画像撮影システムが知られている（例えば、特許文献１、非特許文献１参照）。このＸ線画像撮影システムは、Ｘ線源から見て、被検体の背後に第１のグリッドを配置し、第１のグリッドからタルボ距離だけ下流に第２のグリッドを配置している。第２のグリッドの背後には、Ｘ線を検出して画像を生成するＸ線画像検出器が配置されている。第１のグリッド及び第２のグリッドは、一方向に延伸されたＸ線吸収部及びＸ線透過部を、延伸方向に直交する配列方向に沿って交互に配列した縞状のグリッドである。タルボ距離とは、第１のグリッドを通過したＸ線が、タルボ干渉効果によって自己像（縞画像）を形成する距離である An X-ray imaging system using the Talbot interference effect is known as a kind of X-ray phase imaging (see, for example, Patent Document 1 and Non-Patent Document 1). In this X-ray imaging system, the first grid is disposed behind the subject as viewed from the X-ray source, and the second grid is disposed downstream from the first grid by the Talbot distance. An X-ray image detector that detects an X-ray and generates an image is disposed behind the second grid. The first grid and the second grid are striped grids in which X-ray absorbing portions and X-ray transmitting portions extended in one direction are alternately arranged along an arrangement direction orthogonal to the extension direction. The Talbot distance is the distance at which X-rays that have passed through the first grid form a self-image (stripe image) due to the Talbot interference effect.
　このＸ線画像撮影システムでは、第１のグリッドの自己像と第２のグリッドとの重ね合わせにより強度変調された縞画像の被検体による変化に基づき、位相コントラスト画像を取得する。これは縞走査法と呼ばれている。縞走査法では、第１のグリッドに対して第２のグリッドを間欠移動させるとともに、その停止中に撮影を行う。この間欠移動は、第１のグリッドの面にほぼ平行で、かつ第１のグリッドの格子方向にほぼ垂直な方向に、格子ピッチを等分割した一定の走査ピッチずつ行う。Ｘ線画像検出器で得られる各画素値の強度変化から、被検体でのＸ線の屈折角度の分布を表す位相微分画像が得られる。この位相微分画像から位相コントラスト画像が得られる。この縞走査法は、レーザ光を利用した撮影装置においても用いられている（例えば、非特許文献２参照）。 In this X-ray imaging system, a phase contrast image is acquired based on a change in a striped image intensity-modulated by superimposing the self-image of the first grid and the second grid depending on the subject. This is called a fringe scanning method. In the fringe scanning method, the second grid is intermittently moved with respect to the first grid, and photographing is performed while the second grid is stopped. This intermittent movement is performed at a constant scanning pitch obtained by equally dividing the grid pitch in a direction substantially parallel to the plane of the first grid and substantially perpendicular to the grid direction of the first grid. From the intensity change of each pixel value obtained by the X-ray image detector, a phase differential image representing the distribution of the X-ray refraction angle in the subject is obtained. A phase contrast image is obtained from this phase differential image. This fringe scanning method is also used in an imaging apparatus using laser light (see, for example, Non-Patent Document 2).
　第１及び第２のグリッドは、Ｘ線吸収部が数μｍのピッチで配列された微細構造を有する。このＸ線吸収部には、高いＸ線吸収性が求められる。特に、第２のグリッドのＸ線吸収部は、縞画像を確実に強度変調させるために、第１のグリッドのＸ線吸収部よりも高いＸ線吸収性が必要である。このため、第１及び第２のグリッドのＸ線吸収部は、原子量の重い金（Ａｕ）で形成されている。第２のグリッドのＸ線吸収部は、Ｘ線の進行方向に対して比較的大きな厚みを有し、アスペクト比（Ｘ線を吸収する部分における厚みを幅で除算した値）が高いことが必要である。 The first and second grids have a fine structure in which X-ray absorbers are arranged at a pitch of several μm. This X-ray absorption part is required to have high X-ray absorption. In particular, the X-ray absorption part of the second grid needs higher X-ray absorption than the X-ray absorption part of the first grid in order to surely modulate the intensity of the fringe image. For this reason, the X-ray absorption parts of the first and second grids are made of heavy atomic weight gold (Au). The X-ray absorption part of the second grid needs to have a relatively large thickness with respect to the X-ray traveling direction and have a high aspect ratio (a value obtained by dividing the thickness of the part that absorbs X-rays by the width). It is.
　第１及び第２のグリッドを製造する方法として、シリコン半導体プロセスを用いることが考えられる。しかし、シリコン半導体プロセスは、製造されるグリッドの面積がウエハのサイズに制限されるため、ウエハのサイズより大きな大面積のグリッドを製造することができない。位相イメージングでは、撮影範囲が第１及び第２グリッドのサイズに制限されるため、グリッドの大面積化が望まれている。そこで、小面積のグリッド（以下、小グリッドと呼ぶ）を複数並べることにより、大面積のグリッドを構成することが知られている（例えば、特許文献１、２参照）。 It is conceivable to use a silicon semiconductor process as a method of manufacturing the first and second grids. However, the silicon semiconductor process cannot manufacture a grid having a large area larger than the size of the wafer because the area of the grid to be manufactured is limited to the size of the wafer. In phase imaging, since the imaging range is limited to the size of the first and second grids, it is desired to increase the area of the grid. Thus, it is known that a large-area grid is formed by arranging a plurality of small-area grids (hereinafter referred to as small grids) (see, for example, Patent Documents 1 and 2).
　また、Ｘ線源から放射されたＸ線はコーンビーム状に広がるので、平板状のグリッドでは、グリッドの周縁部におけるＸ線のケラレが問題となる。特許文献１には、複数の小グリッドを凹面上に配置して大面積のグリッドを構成することにより、ケラレを低減することが開示されている。また、特許文献２には、複数の小グリッドを凹面上に配置して収束構造を有する大面積のグリッドを構成し、更に小グリッドを湾曲させることが開示されている。 In addition, since the X-rays emitted from the X-ray source spread in a cone beam shape, the vignetting of the X-rays at the periphery of the grid becomes a problem in a flat grid. Patent Document 1 discloses that vignetting is reduced by arranging a plurality of small grids on a concave surface to form a large-area grid. Patent Document 2 discloses that a plurality of small grids are arranged on a concave surface to form a large-area grid having a converging structure, and further the small grids are curved.
特開２００７－２０３０６１号公報JP 2007-203061 A 特開平０９－３０４７３８号公報JP 09-304738 A
　しかしながら、特許文献１、２に記載のように、複数の小グリッドを凹面上に配置して大面積のグリッドを構成すると、平板状のグリッドに比べて、凹面形状の分だけ全体としての厚みが厚くなってしまう。更に、小グリッドを湾曲させた場合には、各小グリッドに応力が発生し、小グリッドに割れや剥がれ等が生じてしまう。小グリッドが割れたり剥がれたりすると、Ｘ線吸収部及びＸ線透過部のピッチが不規則になり、位相コントラスト画像の品質が劣化する。 However, as described in Patent Documents 1 and 2, when a large area grid is configured by arranging a plurality of small grids on the concave surface, the thickness of the concave surface as a whole is larger than the flat grid. It will be thick. Furthermore, when the small grid is curved, stress is generated in each small grid, and the small grid is cracked or peeled off. If the small grid is cracked or peeled off, the pitch of the X-ray absorption part and the X-ray transmission part becomes irregular, and the quality of the phase contrast image deteriorates.
　本発明の目的は、グリッド部を湾曲させずに収束構造の大面積のグリッドを得ることにある。 An object of the present invention is to obtain a large-area grid having a converging structure without bending the grid portion.
　上記課題を解決するために、本発明の放射線画像撮影用グリッドは、放射線吸収部及び放射線透過部を交互に配列した平板状の複数のグリッド部と、放射線源の焦点を向くように、前記各グリッド部を所定の角度に傾斜した状態で支持する支持部と、を備えている。 In order to solve the above-mentioned problems, the grid for radiographic imaging of the present invention includes a plurality of plate-like grid portions in which radiation absorbing portions and radiation transmitting portions are alternately arranged, and each of the above-mentioned respective so as to face the focal point of the radiation source. And a support portion that supports the grid portion in a state where the grid portion is inclined at a predetermined angle.
　前記支持部を支持する平板状の支持基板をさらに備えることが好ましい。この場合、前記支持部は、前記各グリッド部ごとに個別に設けられた複数の支持台を有することが好ましい。また、前記各支持台は、前記支持基板上の位置に応じた角度で前記グリッド部を傾斜させることが好ましい。 It is preferable to further include a flat support substrate that supports the support portion. In this case, it is preferable that the support part has a plurality of support tables individually provided for each grid part. Moreover, it is preferable that each said support stand inclines the said grid part at an angle according to the position on the said support substrate.
　また、前記各支持台は、前記グリッド部の製造時の下地基板であり、放射線透過性を有することが好ましい。また、前記各支持台は、前記グリッド部の放射線入射側とは反対の面に接合され、放射線透過性を有することが好ましい。 Further, each of the support bases is a base substrate at the time of manufacturing the grid portion, and preferably has radiation transparency. Moreover, it is preferable that each said support stand is joined to the surface on the opposite side to the radiation-incidence side of the said grid part, and has a radiation transmittance.
　また、前記支持部は、傾斜角の異なる複数の傾斜面を有し、前記各傾斜面に前記グリッド部がそれぞれ接合されていることが好ましい。 Further, it is preferable that the support portion has a plurality of inclined surfaces having different inclination angles, and the grid portions are respectively joined to the inclined surfaces.
　また、本発明の放射線画像撮影用グリッドの製造方法は、放射線吸収部及び放射線透過部を交互に配列した平板状のグリッド部を形成するグリッド部形成工程と、前記グリッド部を所定の角度に傾斜した状態で支持する支持台を形成する支持台形成工程と、前記グリッド部を支持する前記支持台を、平板状の支持基板に複数個接合する接合工程と、を備えている。 In addition, the method for manufacturing a radiographic imaging grid according to the present invention includes a grid portion forming step of forming a flat grid portion in which radiation absorbing portions and radiation transmitting portions are alternately arranged, and the grid portion is inclined at a predetermined angle. A support base forming step of forming a support base that supports the grid portion, and a joining step of joining a plurality of the support bases supporting the grid portion to a flat support substrate.
　前記支持台形成工程は、前記グリッド部と、前記支持台としての下地基板とを所定の角度に傾斜させた状態で保持する基材保持工程と、前記支持基板の表面と平行な研磨面を有する研磨装置で前記下地基板を研磨することにより、前記支持基板との接合面を形成する研磨工程と、を含むことが好ましい。 The support table forming step includes a base material holding step for holding the grid portion and the base substrate as the support table in a state inclined at a predetermined angle, and a polishing surface parallel to the surface of the support substrate. It is preferable to include a polishing step of forming a bonding surface with the support substrate by polishing the base substrate with a polishing apparatus.
　また、前記支持台形成工程は、放射線透過性を有する基材を所定の角度に傾斜した状態で保持する基材保持工程と、前記支持基板の表面と平行な研磨面を有する研磨装置で前記基材を研磨することにより、前記支持基板との接合面を形成する研磨工程と、前記研磨工程後に、前記基材を前記支持台として前記グリッド部に接合するグリッド部接合工程と、を含むことが好ましい。 Further, the support table forming step includes a base material holding step for holding a base material having radiation transparency in a state inclined at a predetermined angle, and a polishing apparatus having a polishing surface parallel to the surface of the support substrate. A polishing step of forming a bonding surface with the support substrate by polishing a material, and a grid portion bonding step of bonding the base material to the grid portion as the support base after the polishing step. preferable.
　本発明の放射線画像撮影システムは、放射線源から放射された放射線を通過させて縞画像を生成する第１のグリッドと、前記縞画像に強度変調を与える第２のグリッドと、前記第２のグリッドにより強度変調された縞画像を検出する放射線画像検出器とを有し、前記放射線画像検出器により検出された縞画像から位相コントラスト画像を生成する放射線画像撮影システムにおいて、前記第１または第２のグリッドの少なくとも一方は、放射線吸収部及び放射線透過部を交互に配列した平板状の複数のグリッド部と、放射線源の焦点を向くように、前記各グリッド部を所定の角度に傾斜した状態で支持する支持部と、を備えている。 The radiographic imaging system of the present invention includes a first grid that generates a fringe image by passing radiation emitted from a radiation source, a second grid that applies intensity modulation to the fringe image, and the second grid. A radiographic image detector for detecting a fringe image intensity-modulated by the radiographic image detector, and generating a phase contrast image from the fringe image detected by the radiographic image detector. At least one of the grids is supported in a state where each of the grid portions is inclined at a predetermined angle so as to face the focal point of the radiation source and a plurality of flat grid portions in which radiation absorbing portions and radiation transmitting portions are alternately arranged. And a supporting part.
　前記放射線源と前記第１のグリッドとの間に配置され、前記放射線源から照射された放射線を領域選択的に遮蔽して多数のライン状の放射線を形成する第３のグリッドをさらに備え、この第３グリッドは、放射線吸収部及び放射線透過部を交互に配列した平板状の複数のグリッド部と、放射線源の焦点を向くように、前記各グリッド部を所定の角度に傾斜した状態で支持する支持部と、を有している。 A third grid disposed between the radiation source and the first grid and configured to selectively shield the radiation emitted from the radiation source to form a plurality of line-shaped radiation; The third grid supports the plurality of flat grid portions in which the radiation absorption portions and the radiation transmission portions are alternately arranged, and the respective grid portions inclined at a predetermined angle so as to face the focal point of the radiation source. And a support part.
　本発明によれば、平板状の複数のグリッド部によって構成されているので、容易に大面積化することができる。また、各グリッド部は、放射線焦点を向くように支持部によって支持されているので、平板状でありながら収束構造のグリッドを構成することができる。 According to the present invention, since it is configured by a plurality of flat grid portions, the area can be easily increased. Moreover, since each grid part is supported by the support part so that it may face a radiation focus, it can comprise the grid of a convergence structure, although it is flat form.
Ｘ線画像撮影システムの構成を示す斜視図である。1 is a perspective view showing a configuration of an X-ray image capturing system. 第２のグリッドの平面図である。It is a top view of the 2nd grid. 図２ＡのＩＩＢ－ＩＩＢ線に沿う断面図である。FIG. 2B is a cross-sectional view taken along the line IIB-IIB in FIG. 2A. 小グリッドのＹ方向断面を示す断面図である。It is sectional drawing which shows the Y direction cross section of a small grid. 小グリッドの製造手順１を示す断面図である。It is sectional drawing which shows the manufacture procedure 1 of a small grid. 小グリッドの製造手順２を示す断面図である。It is sectional drawing which shows the manufacturing procedure 2 of a small grid. 小グリッドの製造手順３を示す断面図である。It is sectional drawing which shows the manufacturing procedure 3 of a small grid. 小グリッドの製造手順４を示す断面図である。It is sectional drawing which shows the manufacture procedure 4 of a small grid. 下地基板の研磨工程を説明する説明図である。It is explanatory drawing explaining the grinding | polishing process of a base substrate. 小グリッドを示す斜視図である。It is a perspective view which shows a small grid. 小グリッドの支持基板への接合工程を説明する説明図である。It is explanatory drawing explaining the joining process to the support substrate of a small grid. 小グリッドと支持基板との位置調整工程を説明する説明図である。It is explanatory drawing explaining the position adjustment process of a small grid and a support substrate. 第２実施形態の研磨工程を説明する説明図である。It is explanatory drawing explaining the grinding | polishing process of 2nd Embodiment. 第２実施形態の接合工程を説明する説明図である。It is explanatory drawing explaining the joining process of 2nd Embodiment. 第３実施形態における基材の研磨工程を説明する説明図である。It is explanatory drawing explaining the grinding | polishing process of the base material in 3rd Embodiment. 研磨工程により形成された支持台を示す側面図である。It is a side view which shows the support stand formed by the grinding | polishing process. 第３実施形態のグリッド部と支持台との接合工程を説明する説明図である。It is explanatory drawing explaining the joining process of the grid part of 3rd Embodiment, and a support stand. 第３実施形態の小グリッドと支持基板との接合工程を説明する説明図である。It is explanatory drawing explaining the joining process of the small grid of 3rd Embodiment, and a support substrate. 第３実施形態の小グリッドに水平部材を貼り付けた例を示す側面図である。It is a side view which shows the example which affixed the horizontal member on the small grid of 3rd Embodiment. 支持台の第１の変形例を示す側面図である。It is a side view which shows the 1st modification of a support stand. 支持台の第２の変形例を示す側面図である。It is a side view which shows the 2nd modification of a support stand. 第４実施形態のグリッドを示す図であり、（Ａ）は平面図、（Ｂ）はＸＶＢ－ＸＶＢ線に沿う断面図、（Ｃ）はＸＶＣ－ＸＶＣ線に沿う断面図である。It is a figure which shows the grid of 4th Embodiment, (A) is a top view, (B) is sectional drawing which follows a XVB-XVB line, (C) is sectional drawing which follows a XVC-XVC line. 第５実施形態のグリッドを示す断面図である。It is sectional drawing which shows the grid of 5th Embodiment. 第６実施形態のグリッドを示す断面図である。It is sectional drawing which shows the grid of 6th Embodiment. 第７実施形態のグリッドを示す断面図である。It is sectional drawing which shows the grid of 7th Embodiment.
［第１実施形態］
　図１において、Ｘ線画像撮影システム１０は、Ｘ線照射方向であるＺ方向に沿って配置されたＸ線源１１、線源グリッド（source grid）１２、第１のグリッド１３、第２のグリッド１４、及びＸ線画像検出器１５を備えている。 [First Embodiment]
In FIG. 1, an X-ray imaging system 10 includes an X-ray source 11, a source grid 12, a first grid 13, and a second grid arranged along the Z direction that is an X-ray irradiation direction. 14 and an X-ray image detector 15.
　Ｘ線源１１は、周知のように、回転陽極型のＸ線管（図示せず）と、Ｘ線の照射野を制限するコリメータ（図示せず）とを有し、被検体ＨにＸ線を放射する。線源グリッド１２、第１のグリッド１３及び第２のグリッド１４は、Ｘ線を吸収する吸収型グリッドであり、Ｚ方向においてＸ線源１１に対向配置されている。線源グリッド１２と第１のグリッド１３との間には、被検体Ｈが配置可能な間隔が設けられている。第１のグリッド１３と第２のグリッド１４との距離は、最小のタルボ距離以下とされている。Ｘ線画像検出器１５は、周知のように、半導体回路を用いたフラットパネル検出器であり、第２のグリッド１４の背後に配置されている。 As is well known, the X-ray source 11 has a rotary anode type X-ray tube (not shown) and a collimator (not shown) for limiting the X-ray irradiation field, and the subject H is irradiated with X-rays. Radiate. The radiation source grid 12, the first grid 13, and the second grid 14 are absorption grids that absorb X-rays, and are disposed to face the X-ray source 11 in the Z direction. Between the radiation source grid 12 and the first grid 13, an interval at which the subject H can be arranged is provided. The distance between the first grid 13 and the second grid 14 is not more than the minimum Talbot distance. As is well known, the X-ray image detector 15 is a flat panel detector using a semiconductor circuit, and is disposed behind the second grid 14.
　第２のグリッド１４を例にして、グリッドの構造を説明する。図２Ａ及び図２Ｂにおいて、第２のグリッド１４は、５枚の小グリッド１７～２１と、接着材２２を介して小グリッド１７～２１が接合された支持基板２３とで構成されている。支持基板２３は、ガラス、カーボン、アクリル等の高いＸ線透過性を有する材料によって形成されている。接着剤２２は、Ｘ線透過性を有する有機系接着剤である。小グリッド１７～２１のうち、隣り合う小グリッドの間の隙間は、Ｘ線吸収性を有する材料により埋められている。 The grid structure will be described by taking the second grid 14 as an example. 2A and 2B, the second grid 14 is composed of five small grids 17 to 21 and a support substrate 23 to which the small grids 17 to 21 are bonded via an adhesive 22. The support substrate 23 is made of a material having high X-ray transparency, such as glass, carbon, and acrylic. The adhesive 22 is an organic adhesive having X-ray transparency. Among the small grids 17 to 21, a gap between adjacent small grids is filled with a material having X-ray absorption.
　各小グリッド１７～２１は、Ｘ方向に伸びた細長い矩形状である。小グリッド１７～２１は、支持基板２３上にＹ方向に並べられている。各小グリッド１７～２１は、Ｘ線源１１のＸ線焦点１１ａを向くように、それぞれ異なる角度で傾斜されている。このように、第２のグリッド１４は、コーンビーム状のＸ線に対応した収束構造であるため、Ｘ線のケラレが少ない。なお、第２のグリッド１４を収束構造に構成するためには、最低でも２枚の小グリッドが必要である。適正な収束構造を得るには小グリッドの枚数はできるだけ多いことが好ましい。 Each small grid 17 to 21 has an elongated rectangular shape extending in the X direction. The small grids 17 to 21 are arranged in the Y direction on the support substrate 23. The small grids 17 to 21 are inclined at different angles so as to face the X-ray focal point 11a of the X-ray source 11. Thus, since the second grid 14 has a converging structure corresponding to cone-beam X-rays, X-ray vignetting is small. In order to configure the second grid 14 in a convergent structure, at least two small grids are required. In order to obtain an appropriate convergence structure, the number of small grids is preferably as large as possible.
　小グリッド１７～２１は、グリッド部１７ａ～２１ａと、下地基板１７ｂ～２１ｂとを備えている。下地基板１７ｂ～２１ｂは、グリッド部１７ａ～２１ａをＸ線源１１のＸ線焦点を向くように傾斜させた状態で支持する支持部を構成する。図３において、グリッド部１７ａは、Ｘ線吸収部２５及びＸ線透過部２６を備える。Ｘ線吸収部２５及びＸ線透過部２６は、ほぼＸ方向に延伸され、Ｘ方向にほぼ直交するＹ方向に沿って交互に配列されている。Ｘ線吸収部２５は、金やプラチナ等のＸ線吸収性を有する材料により形成されている。Ｘ線透過部２６は、シリコン等のＸ線透過性を有する材料により形成されている。 The small grids 17 to 21 include grid portions 17a to 21a and base substrates 17b to 21b. The base substrates 17b to 21b constitute a support portion that supports the grid portions 17a to 21a in an inclined state so as to face the X-ray focal point of the X-ray source 11. In FIG. 3, the grid part 17 a includes an X-ray absorption part 25 and an X-ray transmission part 26. The X-ray absorption part 25 and the X-ray transmission part 26 are extended substantially in the X direction and are alternately arranged along the Y direction substantially orthogonal to the X direction. The X-ray absorption part 25 is formed of a material having X-ray absorption such as gold or platinum. The X-ray transmission part 26 is made of a material having X-ray transmission properties such as silicon.
　Ｘ線吸収部２５の幅Ｗ２及びピッチＰ２は、線源グリッド１２と第１のグリッド１３との間の距離、第１のグリッド１３と第２のグリッド１４との間の距離、及び第１のグリッド１３のＸ線吸収部のピッチ等によって決まる。幅Ｗ２は、２～２０μｍ程度である。ピッチＰ２は、４～４０μｍ程度である。また、Ｘ線吸収部２５のＺ方向の厚みＴ２は、高いＸ線吸収性を得るためには厚いほどよいが、Ｘ線源１１から放射されるコーンビーム状のＸ線のケラレを考慮して、１００μｍ程度とすることが好ましい。本実施形態では、例えば、幅Ｗ２を２．５μｍ、ピッチＰ２を５μｍ、厚みＴ２を１００μｍとする。なお、他のグリッド部１８ａ、１９ａ、２０ａ、２１ａは、グリッド部１７ａと同様の構成であるため、詳しい説明は省略する。 The width W2 and the pitch P2 of the X-ray absorber 25 are the distance between the source grid 12 and the first grid 13, the distance between the first grid 13 and the second grid 14, and the first It is determined by the pitch of the X-ray absorption part of the grid 13 or the like. The width W2 is about 2 to 20 μm. The pitch P2 is about 4 to 40 μm. Further, the thickness T2 in the Z direction of the X-ray absorber 25 is preferably as thick as possible in order to obtain high X-ray absorption, but considering the vignetting of cone-beam X-rays emitted from the X-ray source 11. The thickness is preferably about 100 μm. In the present embodiment, for example, the width W2 is 2.5 μm, the pitch P2 is 5 μm, and the thickness T2 is 100 μm. In addition, since the other grid parts 18a, 19a, 20a, and 21a are the structures similar to the grid part 17a, detailed description is abbreviate | omitted.
　下地基板１７ｂ～２１ｂは、グリッド部１７ａ～２１ａの下面に接合された補強用の基板であり、ガラス、カーボン、アクリル等の高いＸ線透過性を有する材料によって形成されている。下地基板１７ｂ～２１ｂは、支持基板２３に接合される接合面１７ｃ～２１ｃを有する。接合面１７ｃ～２１ｃは、グリッド部１７ａ～２１ａがそれぞれＸ線焦点１１ａを向くように、所定の角度に傾斜している。また、第２のグリッド１４の全体としての厚みを薄くするため、傾斜角度の最も大きな外縁部の小グリッド１７、２１の下地基板１７ｂ、２１ｂは、小グリッド１７、２１の高さが小グリッド１８～２０の高さと同程度になるように薄く形成されている。 The base substrates 17b to 21b are reinforcing substrates joined to the lower surfaces of the grid portions 17a to 21a, and are formed of a material having high X-ray transmissivity such as glass, carbon, and acrylic. The base substrates 17 b to 21 b have bonding surfaces 17 c to 21 c that are bonded to the support substrate 23. The joint surfaces 17c to 21c are inclined at a predetermined angle so that the grid portions 17a to 21a face the X-ray focal point 11a. In addition, in order to reduce the overall thickness of the second grid 14, the base substrates 17 b and 21 b of the small grids 17 and 21 at the outer edge portion having the largest inclination angle are small in the height of the small grids 17 and 21. It is formed thin so as to be approximately the same as the height of ˜20.
　線源グリッド１２及び第１のグリッド１３は、第２のグリッド１４と同様に、複数の小グリッドと、小グリッドが接着剤によって接合された支持基板とで構成されている。また、線源グリッド１２及び第１のグリッド１３の小グリッドは、第２のグリッド１４と同様にグリッド部及び下地基板を備えている。このグリッド部は、Ｘ方向に延伸されＸ方向に直交するＹ方向に沿って交互に配列されたＸ線吸収部及びＸ線透過部を備えている。このＸ線吸収部及びＸ線透過部は、Ｙ方向の幅及びピッチと、Ｚ方向の厚さ等が異なる以外は第２のグリッド１３とほぼ同様の構成であるため、詳しい説明は省略する。 The source grid 12 and the first grid 13 are composed of a plurality of small grids and a support substrate in which the small grids are bonded together with an adhesive, like the second grid 14. Further, the small grids of the source grid 12 and the first grid 13 are provided with a grid portion and a base substrate as in the case of the second grid 14. The grid portion includes X-ray absorption portions and X-ray transmission portions that are extended in the X direction and alternately arranged along the Y direction orthogonal to the X direction. Since the X-ray absorption part and the X-ray transmission part have substantially the same configuration as the second grid 13 except that the width and pitch in the Y direction, the thickness in the Z direction, and the like are different, detailed description thereof is omitted.
　次に、第２のグリッド１４を例にして、本発明のグリッドの製造方法について説明する。なお、小グリッド１８～２１も同様の手順で製造されるため、詳しい説明は省略する。図４Ａにおいて、シリコン等により形成されたＸ線透過性基板２７の下面に下地基板１７ｂが接合される。下地基板１７ｂのＸ線透過性基板２７に接合された面には、導電性を有するシーズ層２８が設けられている。シーズ層２８には、例えば、ＡｕまたはＮｉ、もしくはＡｌ、Ｔｉ、Ｃｒ、Ｃｕ、Ａｇ、Ｔａ、Ｗ、Ｐｂ、Ｐｄ、Ｐｔ等の金属膜、あるいはそれらの合金を材料とする金属膜が用いられる。なお、シーズ層２８は、下地基板１７ｂに限られず、Ｘ線透過性基板２７に設けてもよいし、Ｘ線透過性基板２７と下地基板１７ｂとの両方に設けてもよい。 Next, the method for manufacturing the grid of the present invention will be described using the second grid 14 as an example. Since the small grids 18 to 21 are manufactured in the same procedure, detailed description is omitted. In FIG. 4A, the base substrate 17b is bonded to the lower surface of the X-ray transparent substrate 27 formed of silicon or the like. A conductive seed layer 28 is provided on the surface of the base substrate 17b bonded to the X-ray transparent substrate 27. For the seed layer 28, for example, a metal film such as Au or Ni, or a metal film such as Al, Ti, Cr, Cu, Ag, Ta, W, Pb, Pd, and Pt, or an alloy thereof is used. . The seed layer 28 is not limited to the base substrate 17b, but may be provided on the X-ray transparent substrate 27, or may be provided on both the X-ray transparent substrate 27 and the base substrate 17b.
　図４Ｂにおいて、一般的なフォトリソグラフィ技術を用いて、Ｘ線透過性基板２７の上にエッチングマスク３０が形成される。エッチングマスク３０は、Ｘ方向に直線状に延伸され、かつＹ方向に所定ピッチで周期的に配列された縞模様のパターンを有する。 4B, an etching mask 30 is formed on the X-ray transmissive substrate 27 by using a general photolithography technique. The etching mask 30 has a striped pattern that extends linearly in the X direction and is periodically arranged at a predetermined pitch in the Y direction.
　図４Ｃにおいて、エッチングマスク３０を用いたドライエッチングにより、Ｘ線透過性基板２７に、複数の溝３２が形成されるとともに、複数のＸ線透過部２６が形成される。溝３２は、幅数μｍ、深さ１００μｍ程度の高いアスペクト比を必要とする。このため、溝３２を形成するドライエッチングには、ボッシュプロセス、クライオプロセス等の深堀用のドライエッチングが用いられる。なお、シリコンに代えて感光性レジストを用いてＸ線透過性基板２７を形成し、シンクロトロン放射光で露光することにより溝を形成してもよい。 4C, by dry etching using the etching mask 30, a plurality of grooves 32 and a plurality of X-ray transmission portions 26 are formed in the X-ray transmission substrate 27. The groove 32 requires a high aspect ratio with a width of several μm and a depth of about 100 μm. For this reason, for the dry etching for forming the grooves 32, deep etching such as a Bosch process or a cryo process is used. The groove may be formed by forming the X-ray transparent substrate 27 using a photosensitive resist instead of silicon and exposing it with synchrotron radiation.
　図４Ｄにおいて、電解メッキにより溝３２内に金などのＸ線吸収材が充填され、Ｘ線吸収部２５が形成される。Ｘ線透過性基板２７は、下地基板１７ｂに保持されたまま、シーズ層２８に電流端子が接続されて、メッキ液中に浸漬される。Ｘ線透過性基板２７と対向させた位置には、もう一方の電極（陽極）が用意され、電流端子と陽極との間に電流が流される。メッキ液中の金属イオンがパターン加工されたＸ線透過性基板２７に析出されることにより、溝３２内に金が埋め込まれる。この後、エッチングマスク３０がアッシング法等を用いて除去される。 4D, the groove 32 is filled with an X-ray absorbing material such as gold by electrolytic plating, and the X-ray absorbing portion 25 is formed. The X-ray transparent substrate 27 is immersed in the plating solution with the current terminal connected to the sheath layer 28 while being held on the base substrate 17b. The other electrode (anode) is prepared at a position facing the X-ray transparent substrate 27, and a current flows between the current terminal and the anode. By depositing metal ions in the plating solution on the patterned X-ray transparent substrate 27, gold is embedded in the grooves 32. Thereafter, the etching mask 30 is removed using an ashing method or the like.
なお、溝３２へのＸ線吸収材の充填方法は、電解メッキ法に限定されず、例えば、Ｘ線吸収材をペースト状やコロイド状として充填してもよい。この場合にはシーズ層２８は不要である。 In addition, the filling method of the X-ray absorber in the groove 32 is not limited to the electrolytic plating method, and for example, the X-ray absorber may be filled as a paste or a colloid. In this case, the seeds layer 28 is unnecessary.
　図５において、下地基板１７ｂの下部が斜めにカットされ、傾斜した接合面１７ｃが形成される。このとき、小グリッド１７は、エアー吸引によりグリッド部１７ａを吸着する研磨用ホルダ３４により保持される。研磨用ホルダ３４は、吸着を行なう吸着面３４ａが、所定の角度に傾斜している。研磨用ホルダ３４は、移動機構（図示せず）により、研磨装置３６の研磨板３５の上方に移動される。下地基板１７ｂは、研磨用ホルダ３４が研磨装置３６に向けて下降することにより、回転駆動された研磨板３５に押し付けられる。下地基板１７ｂの下部が研磨板３５により研磨されることにより接合面１７ｃが形成される。 In FIG. 5, the lower portion of the base substrate 17b is cut obliquely to form an inclined bonding surface 17c. At this time, the small grid 17 is held by a polishing holder 34 that sucks the grid portion 17a by air suction. In the polishing holder 34, a suction surface 34a for suction is inclined at a predetermined angle. The polishing holder 34 is moved above the polishing plate 35 of the polishing apparatus 36 by a moving mechanism (not shown). The base substrate 17 b is pressed against the polishing plate 35 that is rotationally driven when the polishing holder 34 is lowered toward the polishing device 36. The lower surface of the base substrate 17b is polished by the polishing plate 35, whereby the bonding surface 17c is formed.
　図６において、下地基板１７ｂの接合面１７ｃの２つの角部にアライメントマーク３８が設けられる。アライメントマーク３８は、例えば、グリッド部１７ａのグリッドパターンに関連した所定位置に設けられる。このグリッドパターンの認識は、例えば、撮像装置（図示せず）により撮影することにより得られた画像に基づいて行う。アライメントマーク３８は、下地基板１７ｂに溝を刻み込むことにより形成してもよいし、Ｘ線透過性を有する材料を用いて接合面１７ｃ上に形成してもよい。Ｘ線透過性を有する材料を用いてアライメントマーク３８を形成する場合には、アライメントマーク３８の厚みは、支持基板２３への接合に支障をきたさないように、０．０１～１μｍ程度であることが好ましい。 In FIG. 6, alignment marks 38 are provided at two corners of the bonding surface 17c of the base substrate 17b. For example, the alignment mark 38 is provided at a predetermined position related to the grid pattern of the grid portion 17a. The recognition of the grid pattern is performed based on, for example, an image obtained by photographing with an imaging device (not shown). The alignment mark 38 may be formed by cutting a groove in the base substrate 17b, or may be formed on the bonding surface 17c using a material having X-ray transparency. When the alignment mark 38 is formed using a material having X-ray transparency, the thickness of the alignment mark 38 is about 0.01 to 1 μm so as not to hinder the bonding to the support substrate 23. Is preferred.
　図７において、小グリッド１７が支持基板２３に接合される。このとき、小グリッド１７は、エアー吸引によりグリッド部１７ａを吸着する接合用ホルダ４０により保持される。接合用ホルダ４０は、吸着を行なう吸着面４０ａが、接合面１７ｃの角度に合わせて傾斜している。したがって、小グリッド１７は、接合面１７ｃが水平な状態に保持される。接合用ホルダ４０は、移動機構（図示せず）により、接着剤２２が塗布された支持基板２３の上方に移動される。 7, the small grid 17 is bonded to the support substrate 23. At this time, the small grid 17 is held by a bonding holder 40 that sucks the grid portion 17a by air suction. In the bonding holder 40, the suction surface 40a that performs suction is inclined according to the angle of the joint surface 17c. Accordingly, the small grid 17 is held in a state where the joint surface 17c is horizontal. The joining holder 40 is moved above the support substrate 23 coated with the adhesive 22 by a moving mechanism (not shown).
　図８において、支持基板２３の上面には、小グリッド１７のアライメントマーク３８に対応した一対のアライメントマーク４２が設けられている。小グリッド１７と支持基板２３との間には、２つの位置検出ユニット４５が挿入される。位置検出ユニット４５は、上方及び下方を同時に撮影可能とするように、背中合わせに配置された一対のアライメント用カメラ４３、４４により構成され、アライメントマーク３８、４２がそれぞれのカメラ４３、４４により撮影される。アライメント用カメラ４３、４４により撮影された画像は、画像処理装置（図示せず）によって処理され、アライメントマーク３８とアライメントマーク４２の位置ずれ量が検出される。接合用ホルダ４０の移動機構は、検出された位置ずれ量に基づいて小グリッド１７を移動させ、位置調整を行う。 8, a pair of alignment marks 42 corresponding to the alignment marks 38 of the small grid 17 are provided on the upper surface of the support substrate 23. Two position detection units 45 are inserted between the small grid 17 and the support substrate 23. The position detection unit 45 is composed of a pair of alignment cameras 43 and 44 arranged back to back so that the upper and lower parts can be photographed simultaneously, and the alignment marks 38 and 42 are photographed by the respective cameras 43 and 44. The Images taken by the alignment cameras 43 and 44 are processed by an image processing device (not shown), and the amount of positional deviation between the alignment mark 38 and the alignment mark 42 is detected. The moving mechanism of the bonding holder 40 moves the small grid 17 based on the detected positional deviation amount, and performs position adjustment.
　小グリッド１７の位置調整後、小グリッド１７と支持基板２３との間から位置検出ユニット４５が退避される。そして、接合用ホルダ４０が支持基板２３に向けて下降することにより、下地基板１７ｂが接着剤２２を介して支持基板２３に接合される。接着剤２２としては、Ｘ線透過性を有し、固化時に収縮等の変形をしないものが好ましく、例えば、熱硬化接着剤、瞬間接着剤等が用いられる。また、接着剤の代わりに、Ｘ線透過性を有する低融点金属（例えば、ハンダ、インジウム等）を用いてもよい。 After the position adjustment of the small grid 17, the position detection unit 45 is retracted from between the small grid 17 and the support substrate 23. Then, when the bonding holder 40 is lowered toward the support substrate 23, the base substrate 17 b is bonded to the support substrate 23 via the adhesive 22. The adhesive 22 is preferably one that has X-ray transparency and does not undergo deformation such as shrinkage when solidified. For example, a thermosetting adhesive or an instantaneous adhesive is used. Moreover, you may use the low melting metal (for example, solder | pewter, indium, etc.) which has X-ray permeability instead of an adhesive agent.
　小グリッド１８～２１は、小グリッド１７と同様に製造され、同様に支持基板２３に接合されるため、詳しい説明は省略する。なお、支持基板２３の中央に取り付けられる小グリッド１９は、グリッド部１９ａを傾斜させる必要がないため、小グリッド１９の製造工程では、下地基板１９ｂの研磨工程は省略される。また、線源グリッド１２及び第１のグリッド１３は、第２のグリッド１４と同様に製造されるため、詳しい説明は省略する。 Since the small grids 18 to 21 are manufactured in the same manner as the small grid 17 and are bonded to the support substrate 23 in the same manner, detailed description is omitted. In addition, since the small grid 19 attached to the center of the support substrate 23 does not need to incline the grid part 19a, the grinding | polishing process of the base substrate 19b is abbreviate | omitted in the manufacturing process of the small grid 19. FIG. Further, since the source grid 12 and the first grid 13 are manufactured in the same manner as the second grid 14, a detailed description thereof is omitted.
　次に、Ｘ線画像撮影システムの作用について説明する。Ｘ線源１１から放射されたＸ線は、線源グリッド１２のＸ線吸収部によって部分的に遮蔽されることにより、Ｙ方向に関する実効的な焦点サイズが縮小され、Ｙ方向に配列された多数のライン状のＸ線が形成される。各ライン状のＸ線は、被検体Ｈを通過する際に位相が変化する。この各Ｘ線が第１のグリッド１３を通過することにより、被検体Ｈの屈折率と透過光路長とから決定される被検体Ｈの透過位相情報を反映した縞画像が形成される。各ライン状のＸ線により生成された縞画像は、第２のグリッド１４に投影され、第２のグリッド１４の位置で重なり合う。 Next, the operation of the X-ray imaging system will be described. X-rays radiated from the X-ray source 11 are partially shielded by the X-ray absorption part of the source grid 12, thereby reducing the effective focal size in the Y direction, and arranging many in the Y direction. A line-shaped X-ray is formed. The phase of each line-shaped X-ray changes when passing through the subject H. As each X-ray passes through the first grid 13, a fringe image reflecting the transmission phase information of the subject H determined from the refractive index of the subject H and the transmitted optical path length is formed. The fringe image generated by each line-shaped X-ray is projected onto the second grid 14 and overlaps at the position of the second grid 14.
　縞画像は、第２のグリッド１４により部分的に遮蔽されることにより強度変調される。本実施形態では、縞走査法を用い、第１のグリッド１３に対して第２のグリッド１４を、間欠移動させるとともに、その停止中に、Ｘ線源１１から被検体ＨにＸ線を照射してＸ線画像検出器１５により撮影を行う。この間欠移動は、格子ピッチを等分割（例えば、５分割）した一定の走査ピッチでＹ方向に行う。 The stripe image is intensity-modulated by being partially shielded by the second grid 14. In the present embodiment, the second grid 14 is intermittently moved with respect to the first grid 13 using a fringe scanning method, and X-rays are irradiated from the X-ray source 11 to the subject H during the stop. The X-ray image detector 15 takes an image. This intermittent movement is performed in the Y direction at a constant scanning pitch obtained by equally dividing the lattice pitch (for example, five divisions).
　Ｘ線画像検出器１５の各画素の画素データの強度変化を表す強度変調信号の位相ズレ量（被検体Ｈがある場合とない場合とでの位相のズレ量）を算出することにより、位相微分画像が得られる。位相微分画像は、被検体ＨでのＸ線の屈折角度の分布に対応する。この位相微分画像をＸ方向に沿って積分することにより、位相コントラスト画像が得られる。 By calculating the phase shift amount (the phase shift amount with and without the subject H) of the intensity modulation signal representing the intensity change of the pixel data of each pixel of the X-ray image detector 15, the phase differentiation An image is obtained. The phase differential image corresponds to the distribution of the X-ray refraction angle in the subject H. By integrating this phase differential image along the X direction, a phase contrast image is obtained.
　以上の通り、Ｘ線画像撮影システム１０は、線源グリッド１２、第１のグリッド１３、及び第２のグリッド１４を、それぞれ複数の小グリッドにより構成して大面積化している。このため、半導体プロセスを用いて形成された１枚のグリッドで線源グリッド１２、第１のグリッド１３、及び第２のグリッド１４のそれぞれを構成する場合よりも、撮影面積が拡大する。また、線源グリッド１２、第１のグリッド１３、及び第２のグリッド１４は、Ｘ線焦点１１ａを向くようにそれぞれ異なる角度で傾斜した複数の小グリッドにより構成されているので、全体として厚みが薄い収束構造が得られる。これにより、グリッドの周縁部におけるＸ線のケラレが低減され、高画質な位相コントラスト画像が得られる。 As described above, in the X-ray imaging system 10, the radiation source grid 12, the first grid 13, and the second grid 14 are each configured by a plurality of small grids to increase the area. For this reason, an imaging area expands rather than the case where each of the source grid 12, the first grid 13, and the second grid 14 is configured by one grid formed using a semiconductor process. Moreover, since the source grid 12, the first grid 13, and the second grid 14 are configured by a plurality of small grids that are inclined at different angles so as to face the X-ray focal point 11a, the thickness thereof as a whole is increased. A thin convergence structure is obtained. Thereby, the vignetting of the X-rays at the periphery of the grid is reduced, and a high-quality phase contrast image is obtained.
　以下に、本発明の別の実施形態について説明する。なお、第１実施形態と同じ構成については、同符号を用いて詳しい説明は省略する。また、以下の実施形態では、第２のグリッドについて説明するが、第１のグリッド及び線源グリッドについても同様である。 Hereinafter, another embodiment of the present invention will be described. In addition, about the same structure as 1st Embodiment, detailed description is abbreviate | omitted using a same sign. In the following embodiments, the second grid will be described, but the same applies to the first grid and the source grid.
［第２実施形態］
　第１実施形態では、小グリッド１７～２１を、研磨用ホルダ３４及び接合用ホルダ４０により保持して研磨及び接合を行なっている。このため、下地基板１７ｂ～２１ｂの接合面１７ｃ～２１ｃの傾斜角度に合わせて傾斜した吸着面を持つ、複数種類の研磨用ホルダ３４及び接合用ホルダ４０を用意しなければならず、非効率である。また、小グリッド１７～２１のそれぞれに合わせて研磨用ホルダ３４及び接合用ホルダ４０を交換しなければならないため、製造時のスループットが低い。 [Second Embodiment]
In the first embodiment, the small grids 17 to 21 are held by the polishing holder 34 and the bonding holder 40 for polishing and bonding. For this reason, it is necessary to prepare a plurality of types of polishing holders 34 and bonding holders 40 having suction surfaces inclined in accordance with the inclination angles of the bonding surfaces 17c to 21c of the base substrates 17b to 21b, which is inefficient. is there. Further, since the polishing holder 34 and the joining holder 40 must be exchanged in accordance with each of the small grids 17 to 21, the throughput during manufacturing is low.
　そこで、本第２実施形態では、図９Ａに示すように、小グリッド１７のグリッド部１７ａの上面に水平部材５０をアダプターとして貼り付ける。水平部材５０は、下地基板１７ｂに形成する接合面の角度に合わせて傾斜した下面を有する。本実施形態によれば、下地基板１７ｂを研磨して接合面を形成する際に、水平な吸着面５１ａを有する１種類の研磨用ホルダ５１により水平部材５０を吸着して小グリッド１７を保持することができるため、複数種類の研磨用ホルダを用意する必要がない。 Therefore, in the second embodiment, as shown in FIG. 9A, the horizontal member 50 is attached as an adapter to the upper surface of the grid portion 17a of the small grid 17. The horizontal member 50 has a lower surface inclined in accordance with the angle of the bonding surface formed on the base substrate 17b. According to the present embodiment, when the base substrate 17b is polished to form the bonding surface, the horizontal member 50 is sucked by the one type of polishing holder 51 having the horizontal suction surface 51a to hold the small grid 17. Therefore, it is not necessary to prepare a plurality of types of polishing holders.
　また、本第２実施形態によれば、図９Ｂに示すように、下地基板１７ｂの研磨後に小グリッド１７を支持基板２３に接合する際には、水平な吸着面５３ａを有する１種類の接合用ホルダ５３により水平部材５０を吸着して小グリッド１７を保持することができるため、複数種類の接合用ホルダを容易する必要がない。水平部材５０は、小グリッド１７の支持基板２３への接合後にグリッド部１７ａから取り外すことが好ましいが、水平部材５０をＸ線透過性材料で形成する場合には、該接合後にグリッド部１７ａにそのまま残存させてもよい。 Further, according to the second embodiment, as shown in FIG. 9B, when joining the small grid 17 to the support substrate 23 after polishing the base substrate 17b, one kind of joining having a horizontal suction surface 53a. Since the horizontal member 50 can be adsorbed by the holder 53 and the small grid 17 can be held, it is not necessary to facilitate a plurality of types of joining holders. The horizontal member 50 is preferably removed from the grid portion 17a after the small grid 17 is joined to the support substrate 23. However, when the horizontal member 50 is formed of an X-ray transmissive material, the grid member 17a is not changed as it is after the joining. It may be left.
［第３実施形態］
　第１実施形態では、最終的な小グリッド１７の支持部として、グリッド部１７ａの製造時の下地である下地基板１７ｂを用いているが、下地基板１７ｂを除去して、グリッド部１７ａとは別に形成された支持台を支持部としてもよい。以下、本第３実施形態のグリッドの製造方法を説明する。 [Third Embodiment]
In the first embodiment, the base substrate 17b, which is the base at the time of manufacturing the grid portion 17a, is used as the support portion of the final small grid 17, but the base substrate 17b is removed and separated from the grid portion 17a. It is good also considering the formed support stand as a support part. Hereinafter, a method of manufacturing the grid according to the third embodiment will be described.
　図１０Ａにおいて、支持台の材料となる基材６０を、研磨用ホルダ６１により保持し、研磨装置３６によって研磨する。研磨用ホルダ６１は、所定の角度に傾斜した吸着面６１ａを有し、この吸着面６１ａで基材６０を吸着保持する。基材６０には、ガラス、カーボン、アクリル等のＸ線透過性の高い材料が用いられる。これにより、図１０Ｂに示すように、接合面６２ａを有する支持台６２が形成される。 In FIG. 10A, a base material 60 which is a material for the support base is held by a polishing holder 61 and polished by a polishing apparatus 36. The polishing holder 61 has a suction surface 61a inclined at a predetermined angle, and holds and holds the substrate 60 by the suction surface 61a. The base material 60 is made of a material having high X-ray permeability such as glass, carbon, and acrylic. As a result, as shown in FIG. 10B, a support base 62 having a joint surface 62a is formed.
　図１１において、支持台６２は、接合面６２ａに合わせて傾斜した吸着面６３ａを有する固定ステージ６３により吸着保持される。これにより、支持台６２のグリッド部１７ａを支持する支持面６２ｂは、水平に保たれる。支持面６２ｂには、接着剤６４が塗布される。接着剤６４は、Ｘ線透過性を有し、固化時に変形しない有機系接着剤である。 In FIG. 11, the support base 62 is sucked and held by a fixed stage 63 having a suction surface 63a inclined in accordance with the joining surface 62a. Thereby, the support surface 62b which supports the grid part 17a of the support stand 62 is kept horizontal. An adhesive 64 is applied to the support surface 62b. The adhesive 64 is an organic adhesive that has X-ray transparency and does not deform when solidified.
　グリッド部１７ａは、第１実施形態と同様の製造方法により形成されたものである。グリッド部１７ａは、水平な吸着面６５ａを有する組立用ホルダ６５により保持され、接着剤６４を介して支持台６２の支持面６２ｂに接合される。これにより、グリッド部１７ａと支持台６２とにより構成された小グリッド６６（図１２参照）が完成する。この後、支持台６２の接合面６２ａには、第１実施形態と同様にアライメントマークが形成される。 The grid portion 17a is formed by the same manufacturing method as in the first embodiment. The grid portion 17 a is held by an assembly holder 65 having a horizontal suction surface 65 a and is joined to the support surface 62 b of the support base 62 via an adhesive 64. Thereby, the small grid 66 (refer FIG. 12) comprised by the grid part 17a and the support stand 62 is completed. Thereafter, an alignment mark is formed on the joint surface 62a of the support base 62 as in the first embodiment.
　図１２において、小グリッド６６は、第１実施形態と同様に、接合面６２ａに合わせて傾斜した吸着面６７ａを有する接合用ホルダ６７により保持される。接合面６２ａは、水平に保たれたまま、アライメントマークを利用して位置調整され、接着剤２２を介して支持基板２３に接合される。この後、グリッド部１８ａ～２１ａについても、グリッド部１７ａと同様に支持台を用いて支持基板２３に接合される。 12, the small grid 66 is held by a joining holder 67 having a suction surface 67a inclined in accordance with the joining surface 62a, as in the first embodiment. The position of the bonding surface 62 a is adjusted using the alignment mark while being kept horizontal, and is bonded to the support substrate 23 via the adhesive 22. Thereafter, the grid portions 18a to 21a are also bonded to the support substrate 23 using the support base in the same manner as the grid portion 17a.
　なお、支持台６２の基材としてアクリル等の樹脂材を用いる場合には、研磨等を行わず、樹脂材をそのまま支持台６２の形状に成形してもよい。また、支持台６２を樹脂材で成形する際に、アライメントマークを同時に形成してもよい。これによれば、支持台６２の研磨工程とアライメントマークの形成工程とを省略することできるので、製造時のスループットが向上する。 In addition, when using resin materials, such as an acryl, as a base material of the support stand 62, you may shape | mold the resin material in the shape of the support stand 62 as it is, without grind | polishing. Further, when the support base 62 is formed of a resin material, the alignment mark may be formed at the same time. According to this, since the polishing process of the support base 62 and the alignment mark forming process can be omitted, the throughput during manufacturing is improved.
　また、図１３に示すように、本第３実施形態の小グリッド６６のグリッド部１７ａに、第２実施形態と同様に、アダプターとしての水平部材６８を貼り付け、この水平部材６８を、水平な吸着面６９ａを有する接合用ホルダ６９により保持して支持基板２３に接合してもよい。この水平部材６８は、第２実施形態と同様に、小グリッド６６の支持基板２３への接合後に除去してもよいし、Ｘ線透過性材料で形成する場合にはそのまま残存させてもよい。 Moreover, as shown in FIG. 13, the horizontal member 68 as an adapter is affixed to the grid part 17a of the small grid 66 of this 3rd Embodiment similarly to 2nd Embodiment, and this horizontal member 68 is made into horizontal It may be held by the bonding holder 69 having the suction surface 69 a and bonded to the support substrate 23. As in the second embodiment, the horizontal member 68 may be removed after the small grid 66 is bonded to the support substrate 23, or may be left as it is when formed of an X-ray transparent material.
　また、本第３実施形態では、基材６０を研磨して支持台６２を形成しているが、図１４Ａに示すように、幅の異なる平板状の角度部材７５ａ、７５ｂをグリッド部１７ａと端部を揃えて積層することにより、グリッド部１７ａを傾斜させる支持台７６を形成してもよい。また、グリッド部１７ａを位相型グリッドとする場合には、角度部材によるＸ線の回折を防止するため、図１４Ｂに示すように、グリッド部１７ａの外側に角度部材７７を配置するのが好ましい。 In the third embodiment, the support base 62 is formed by polishing the base material 60. However, as shown in FIG. 14A, flat angle members 75a and 75b having different widths are connected to the grid portion 17a and the ends. The support base 76 for inclining the grid portion 17a may be formed by aligning and laminating the portions. When the grid portion 17a is a phase-type grid, it is preferable to place an angle member 77 outside the grid portion 17a as shown in FIG. 14B in order to prevent X-ray diffraction by the angle member.
［第４実施形態］
　第１実施形態では、小グリッド１７～２１をＹ方向に並べて凹面状の収束構造を有するグリッドを形成しているが、小グリッドをマトリクス状に配置して球面状の収束構造を有するグリッドを形成することも可能である。図１５において、第２のグリッド８０は、十字状のグリッドパターンを有する小グリッド８１ａ～８１ｙを支持基板８２のＸＹ平面状にマトリクス状に配置するとともに、各小グリッド８１ａ～８１ｙを下地基板によってＸ線焦点１１ａを向くように傾斜させている。 [Fourth Embodiment]
In the first embodiment, the small grids 17 to 21 are arranged in the Y direction to form a grid having a concave convergence structure. However, the small grids are arranged in a matrix to form a grid having a spherical convergence structure. It is also possible to do. In FIG. 15, the second grid 80 includes small grids 81a to 81y having a cross-shaped grid pattern arranged in a matrix on the XY plane of the support substrate 82, and each of the small grids 81a to 81y is X by a base substrate. It is inclined to face the line focal point 11a.
［第５実施形態］
　上記各実施形態では、小グリッド１７の支持台を、小グリッド１７毎に個別に設けることにより支持部を構成しているが、これらの支持台を一体化して支持部を構成してもよい。図１６Ａにおいて、第２のグリッド９０は、アクリル等の樹脂材で一体的に成形された支持台９１を備える。支持台９１は、Ｘ線源１１のＸ線焦点１１ａを向くようにそれぞれが傾斜した傾斜面９０ａ～９０ｅを有している。各傾斜面９０ａ～９０ｅには、第１実施形態のグリッド部１７ａ～２１ａがそれぞれ接合されている。 [Fifth Embodiment]
In each said embodiment, although the support part is comprised by providing the support stand of the small grid 17 for every small grid 17, these support stands may be integrated and a support part may be comprised. In FIG. 16A, the second grid 90 includes a support base 91 formed integrally with a resin material such as acrylic. The support base 91 has inclined surfaces 90 a to 90 e that are inclined so as to face the X-ray focal point 11 a of the X-ray source 11. The grid portions 17a to 21a of the first embodiment are joined to the inclined surfaces 90a to 90e, respectively.
　本第５実施形態では、一体的な支持台９１を用いているため、複数の小グリッドを支持基板に接合する接合工程が不要であり、製造が容易である。また、各傾斜面９０ａ～９０ｅが平坦であるため、グリッド部１７ａ～２１ａを接合する際に応力による変形や割れが生じることはない。 In the fifth embodiment, since the integral support base 91 is used, a joining step for joining a plurality of small grids to the support substrate is unnecessary, and the manufacturing is easy. Further, since the inclined surfaces 90a to 90e are flat, deformation and cracking due to stress do not occur when the grid portions 17a to 21a are joined.
［第６実施形態］
　第５実施形態では、傾斜面９０ａ～９０ｅがＸ線焦点１１ａを中心とした凹面状に沿って形成されているため、支持台９１は、中央部に比べて外周部の厚さが厚い。このため、支持台９１の中央部と外周部とで熱膨張差が発生し、支持台９１が変形することにより、傾斜面９０ａ～９０ｅの傾斜角が変化することが予想される。 [Sixth Embodiment]
In the fifth embodiment, since the inclined surfaces 90a to 90e are formed along a concave shape centered on the X-ray focal point 11a, the support base 91 has a thicker outer peripheral portion than the central portion. For this reason, a difference in thermal expansion occurs between the central portion and the outer peripheral portion of the support base 91, and it is expected that the inclination angles of the inclined surfaces 90a to 90e change due to the deformation of the support base 91.
　そこで、第６実施形態では、図１６Ｂに示すように、第２のグリッド９２の支持台９３に、傾斜面９３ａ～９３ｅを、Ｚ方向への互いの位置をずらして形成する。これにより、支持台９３のＺ方向への厚さが平均化される。第５実施形態と同様に、各傾斜面９３ａ～９３ｅは、Ｘ線源１１のＸ線焦点１１ａを向くように傾斜しており、第１実施形態のグリッド部１７ａ～２１ａがそれぞれ接合されている。 Therefore, in the sixth embodiment, as shown in FIG. 16B, the inclined surfaces 93a to 93e are formed on the support base 93 of the second grid 92 by shifting their positions in the Z direction. Thereby, the thickness to the Z direction of the support stand 93 is averaged. As in the fifth embodiment, the inclined surfaces 93a to 93e are inclined so as to face the X-ray focal point 11a of the X-ray source 11, and the grid portions 17a to 21a of the first embodiment are joined to each other. .
　支持台９３は、Ｚ方向への厚さが平均化されているため、中央部と外周部とでの熱膨張差が少なく、変形しにくい。これにより、傾斜面９３ａ～９３ｅの傾斜角をほぼ一定に保つことができる。また、本第６実施形態では、第２グリッド９２のＺ方向への全体の厚みを、第５実施形態の第２のグリッド９０より薄くすることができる。 Since the thickness of the support base 93 is averaged in the Z direction, there is little difference in thermal expansion between the central portion and the outer peripheral portion, and it is difficult to deform. Thereby, the inclination angles of the inclined surfaces 93a to 93e can be kept substantially constant. In the sixth embodiment, the overall thickness of the second grid 92 in the Z direction can be made thinner than that of the second grid 90 of the fifth embodiment.
［第７実施形態］
　第７実施形態では、図１６Ｃに示すように、第２のグリッド９４の支持台９５の厚みがほぼ均一である。第５実施形態と同様に、各傾斜面９５ａ～９５ｅは、Ｘ線源１１のＸ線焦点１１ａを向くように傾斜しており、第１実施形態のグリッド部１７ａ～２１ａがそれぞれ接合されている。このため、Ｘ線焦点１１ａから放射されたＸ線の支持台９５の透過量がほぼ均一となる。この支持台９５の構成は、後述するように第１のグリッドを位相型グリッドとする場合に好適である。第１のグリッドの支持台で位相差が生じ難くいため、タルボ干渉効果により高品質な自己像が得られる。 [Seventh Embodiment]
In the seventh embodiment, as shown in FIG. 16C, the thickness of the support base 95 of the second grid 94 is substantially uniform. As in the fifth embodiment, the inclined surfaces 95a to 95e are inclined so as to face the X-ray focal point 11a of the X-ray source 11, and the grid portions 17a to 21a of the first embodiment are joined to each other. . For this reason, the amount of X-ray radiated from the X-ray focal point 11a through the support table 95 is substantially uniform. The configuration of the support table 95 is suitable when the first grid is a phase-type grid as will be described later. Since it is difficult for a phase difference to occur on the support base of the first grid, a high-quality self-image can be obtained by the Talbot interference effect.
［その他の実施形態］
　上記各実施形態は、第１及び第２のグリッドを、そのＸ線透過部を通過したＸ線を線形的（幾何光学的）に投影するように構成しているが、国際公開ＷＯ２００４／０５８０７０号公報（米国特許７１８０９７９号明細書）等に記載のように、Ｘ線透過部でＸ線を回折することによりタルボ干渉効果が生じる構成としてもよい。この場合には、第１及び第２のグリッド間の距離をタルボ距離に設定する必要がある。また、この場合には、第１のグリッドを、吸収型グリッドに代えて、位相型グリッドとすることが可能である。位相型グリッドは、タルボ干渉効果により生じる縞画像（自己像）を、第２のグリッドの位置に形成する。 [Other Embodiments]
In each of the above embodiments, the first and second grids are configured so as to linearly (geometrically optically) project the X-rays that have passed through the X-ray transmission part, but International Publication No. WO 2004/058070. As described in the publication (US Pat. No. 7,180,796) and the like, the Talbot interference effect may be generated by diffracting X-rays at the X-ray transmission part. In this case, it is necessary to set the distance between the first and second grids to the Talbot distance. In this case, the first grid can be a phase grid instead of the absorption grid. The phase type grid forms a fringe image (self-image) generated by the Talbot interference effect at the position of the second grid.
　また、上記実施形態では、被検体ＨをＸ線源と第１のグリッドとの間に配置しているが、被検体Ｈを第１のグリッドと第２のグリッドとの間に配置してもよい。この場合にも同様に位相コントラスト画像が生成される。また、上記実施形態では、線源グリッドを設けているが、線源グリッドを省略してもよい。 In the above embodiment, the subject H is disposed between the X-ray source and the first grid. However, the subject H may be disposed between the first grid and the second grid. Good. In this case as well, a phase contrast image is similarly generated. In the above embodiment, the radiation source grid is provided, but the radiation source grid may be omitted.
　また、上記各実施形態では、一方向に延伸されかつ延伸方向に直交する配列方向に沿って交互に配置されたＸ線吸収部及びＸ線透過部を有する縞状の一次元グリッドを例に説明したが、本発明は、Ｘ線吸収部及びＸ線透過部が直交する２方向に配列された二次元グリッドにも適用が可能である。この場合、複数回の撮影を行う縞走査法により位相コントラスト画像を生成してもよいし、１回の撮影によって位相コントラスト画像を生成してもよい。１回の撮影で位相コントラスト画像を生成するには、例えば、第１のグリッドに市松模様の位相型グリッドを使用し、第２のグリッドに網目模様の振幅型グリッドを使用して、撮影を行う。この１枚の撮影画像にフーリエ変換を行い、縦横方向の１次スペクトルをそれぞれ抽出する。これらの１次スペクトルをフーリエ逆変換することで、２方向の位相微分画像が得られる。 Further, in each of the above embodiments, a striped one-dimensional grid having X-ray absorbing portions and X-ray transmitting portions that are extended in one direction and alternately arranged along the arrangement direction orthogonal to the extending direction will be described as an example. However, the present invention can also be applied to a two-dimensional grid in which the X-ray absorption part and the X-ray transmission part are arranged in two orthogonal directions. In this case, the phase contrast image may be generated by a fringe scanning method in which a plurality of shootings are performed, or the phase contrast image may be generated by a single shooting. In order to generate a phase contrast image by one shooting, for example, a checkered phase type grid is used for the first grid and a net type amplitude type grid is used for the second grid. . This single photographed image is subjected to Fourier transform, and the primary spectra in the vertical and horizontal directions are respectively extracted. By performing inverse Fourier transform on these primary spectra, a phase differential image in two directions is obtained.
　上記各実施形態は、矛盾しない範囲で相互に組み合わせてもよい。本発明は、医療診断用の放射線画像撮影システムのほか、工業用や、非破壊検査等のその他の放射線撮影システムに適用可能である。また、本発明のグリッドは、Ｘ線撮影において散乱線を除去する散乱線除去用グリッドにも適用可能である。更に、本発明は、放射線として、Ｘ線以外にガンマ線等を用いる放射線画像撮影システムにも適用可能である。 The above embodiments may be combined with each other within a consistent range. The present invention is applicable not only to a radiographic imaging system for medical diagnosis but also to other radiographic systems for industrial use and nondestructive inspection. The grid of the present invention can also be applied to a scattered radiation removal grid that removes scattered radiation in X-ray imaging. Furthermore, the present invention can also be applied to a radiographic imaging system that uses gamma rays or the like in addition to X-rays.
　１０　Ｘ線画像撮影システム
　１１　Ｘ線源
　１２　線源グリッド
　１３　第１のグリッド
　１４、８０　第２のグリッド
　１５　Ｘ線画像検出器
　１７～２１、８１ａ～８１ｙ　小グリッド
　１７ａ～２１ａ　グリッド部
　１７ｂ～２１ｂ　下地基板
　１７ｃ～２１ｃ　接合面
　２２　接着剤
　２３　支持基板
　２５　Ｘ線吸収部
　２６　Ｘ線透過部
　３８　アライメントマーク
　５０　水平部材
　６２　支持台 DESCRIPTION OF SYMBOLS 10 X-ray imaging system 11 X-ray source 12 Source grid 13 1st grid 14, 80 2nd grid 15 X-ray image detector 17-21, 81a-81y Small grid 17a-21a Grid part 17b-21b Ground Substrate 17c to 21c Bonding surface 22 Adhesive 23 Support substrate 25 X-ray absorption part 26 X-ray transmission part 38 Alignment mark 50 Horizontal member 62 Support base

Claims (12)

  1. 　放射線吸収部及び放射線透過部を交互に配列した平板状の複数のグリッド部と、
    　放射線源の焦点を向くように、前記各グリッド部を所定の角度に傾斜した状態で支持する支持部と、
    　を備えることを特徴とする放射線画像撮影用グリッド。     A plurality of flat grid portions in which radiation absorbing portions and radiation transmitting portions are alternately arranged;
    A support part that supports each grid part in a state inclined at a predetermined angle so as to face the focal point of the radiation source;
    A grid for radiographic imaging, comprising:
  2. 　前記支持部を支持する平板状の支持基板をさらに備えることを特徴とする請求の範囲第１項に記載の放射線画像撮影用グリッド。 The radiation image capturing grid according to claim 1, further comprising a flat support substrate that supports the support portion.
  3. 　前記支持部は、前記各グリッド部ごとに個別に設けられた複数の支持台を有することを特徴とする請求の範囲第２項に記載の放射線画像撮影用グリッド。 3. The radiographic imaging grid according to claim 2, wherein the support section has a plurality of support bases individually provided for each of the grid sections.
  4. 　前記各支持台は、前記支持基板上の位置に応じた角度で前記グリッド部を傾斜させることを特徴とする請求の範囲第３項に記載の放射線画像撮影用グリッド。 The radiographic imaging grid according to claim 3, wherein each of the support bases inclines the grid portion at an angle corresponding to a position on the support substrate.
  5. 　前記各支持台は、前記グリッド部の製造時の下地基板であり、放射線透過性を有することを特徴とする請求の範囲第３項または第４項に記載の放射線画像撮影用グリッド。 The radiographic imaging grid according to claim 3 or 4, wherein each of the support bases is a base substrate at the time of manufacturing the grid portion, and has radiation transparency.
  6. 　前記各支持台は、前記グリッド部の放射線入射側とは反対の面に接合され、放射線透過性を有することを特徴とする請求の範囲第３項または第４項に記載の放射線画像撮影用グリッド。 The radiographic imaging grid according to claim 3 or 4, wherein each of the support bases is bonded to a surface opposite to the radiation incident side of the grid portion and has radiation transparency. .
  7. 　前記支持部は、傾斜角の異なる複数の傾斜面を有し、前記各傾斜面に前記グリッド部がそれぞれ接合されていることを特徴とする請求の範囲第１項に記載の放射線画像撮影用グリッド。 The radiographic imaging grid according to claim 1, wherein the support portion has a plurality of inclined surfaces having different inclination angles, and the grid portions are joined to the inclined surfaces, respectively. .
  8. 　放射線吸収部及び放射線透過部を交互に配列した平板状のグリッド部を形成するグリッド部形成工程と、
    　前記グリッド部を所定の角度に傾斜した状態で支持する支持台を形成する支持台形成工程と、
    　前記グリッド部を支持する前記支持台を、平板状の支持基板に複数個接合する接合工程と、
    　を備えることを特徴とする放射線画像撮影用グリッドの製造方法。     A grid portion forming step for forming a flat grid portion in which radiation absorbing portions and radiation transmitting portions are alternately arranged;
    A support base forming step for forming a support base for supporting the grid portion in a state inclined at a predetermined angle;
    A bonding step of bonding a plurality of the support bases supporting the grid portion to a flat support substrate;
    The manufacturing method of the grid for radiographic imaging characterized by comprising.
  9. 　前記支持台形成工程は、
    　前記グリッド部と、前記支持台としての下地基板とを所定の角度に傾斜させた状態で保持する基材保持工程と、
    　前記支持基板の表面と平行な研磨面を有する研磨装置で前記下地基板を研磨することにより、前記支持基板との接合面を形成する研磨工程と、
    　を含むことを特徴とする請求の範囲第８項に記載の放射線画像撮影用グリッドの製造方法。     The support table forming step includes
    A base material holding step for holding the grid portion and the base substrate as the support base in a state inclined at a predetermined angle;
    A polishing step of forming a bonding surface with the support substrate by polishing the base substrate with a polishing apparatus having a polishing surface parallel to the surface of the support substrate;
    The manufacturing method of the grid for radiographic imaging of Claim 8 characterized by the above-mentioned.
  10. 　前記支持台形成工程は、
    　放射線透過性を有する基材を所定の角度に傾斜した状態で保持する基材保持工程と、
    　前記支持基板の表面と平行な研磨面を有する研磨装置で前記基材を研磨することにより、前記支持基板との接合面を形成する研磨工程と、
    　前記研磨工程後に、前記基材を前記支持台として前記グリッド部に接合するグリッド部接合工程と、
    　を含むことを特徴とする請求の範囲第８項に記載の放射線画像撮影用グリッドの製造方法。     The support table forming step includes
    A substrate holding step of holding the substrate having radiation transparency in a state inclined at a predetermined angle;
    A polishing step of forming a bonding surface with the support substrate by polishing the base material with a polishing apparatus having a polishing surface parallel to the surface of the support substrate;
    After the polishing step, a grid portion joining step for joining the base material to the grid portion as the support base,
    The manufacturing method of the grid for radiographic imaging of Claim 8 characterized by the above-mentioned.
  11. 　放射線源から放射された放射線を通過させて縞画像を生成する第１のグリッドと、前記縞画像に強度変調を与える第２のグリッドと、前記第２のグリッドにより強度変調された縞画像を検出する放射線画像検出器とを有し、前記放射線画像検出器により検出された縞画像から位相コントラスト画像を生成する放射線画像撮影システムにおいて、
    　前記第１または第２のグリッドの少なくとも一方は、
    　放射線吸収部及び放射線透過部を交互に配列した平板状の複数のグリッド部と、
    　放射線源の焦点を向くように、前記各グリッド部を所定の角度に傾斜した状態で支持する支持部と、
    　を備えることを特徴とする放射線画像撮影システム。     A first grid that generates a fringe image by passing radiation emitted from a radiation source, a second grid that applies intensity modulation to the fringe image, and a fringe image that is intensity-modulated by the second grid are detected. A radiographic imaging system that generates a phase contrast image from a fringe image detected by the radiographic image detector,
    At least one of the first or second grid is
    A plurality of flat grid portions in which radiation absorbing portions and radiation transmitting portions are alternately arranged;
    A support part that supports each grid part in a state inclined at a predetermined angle so as to face the focal point of the radiation source;
    A radiographic imaging system comprising:
  12. 　前記放射線源と前記第１のグリッドとの間に配置され、前記放射線源から照射された放射線を領域選択的に遮蔽して多数のライン状の放射線を形成する第３のグリッドをさらに備え、この第３グリッドは、
    　放射線吸収部及び放射線透過部を交互に配列した平板状の複数のグリッド部と、
    　放射線源の焦点を向くように、前記各グリッド部を所定の角度に傾斜した状態で支持する支持部と、
    　を有することを特徴とする請求の範囲第１１項に記載の放射線画像撮影システム。     A third grid disposed between the radiation source and the first grid and configured to selectively shield the radiation emitted from the radiation source to form a plurality of line-shaped radiation; The third grid is
    A plurality of flat grid portions in which radiation absorbing portions and radiation transmitting portions are alternately arranged;
    A support part that supports each grid part in a state inclined at a predetermined angle so as to face the focal point of the radiation source;
    The radiation image capturing system according to claim 11, comprising:
PCT/JP2011/073066 2010-10-19 2011-10-06 Grid for radiation imaging, method for manufacturing same, and radiation imaging system WO2012053368A1 (en)

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CN109893776A (en) * 2017-12-07 2019-06-18 医科达有限公司 For determining the method and system of radiotherapy harness shape

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JP2001349952A (en) * 2000-06-12 2001-12-21 Fuji Photo Film Co Ltd Scattering ray removing grid
JP2002191596A (en) * 2000-08-24 2002-07-09 General Electric Co <Ge> X-ray scattering preventing grid
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CN103690185A (en) * 2013-02-06 2014-04-02 苏州波影医疗技术有限公司 Adjustable photon detection system for multilayer x-ray computed tomography system
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