Patent Number: 
Section: claims

1. An X-ray imaging apparatus comprising:an X-ray source;a grating configured to divide diverging X-rays irradiated from the X-ray source; anda detector configured to detect X-rays which are divided by the grating and pass through a sample,wherein the grating includes a plurality of transparent objects which pass the diverging X-rays, and a plurality of opaque objects which shield the diverging X-rays,wherein the plurality of opaque objects which shield the diverging X-rays is arranged so that a plurality of extended lines intersects each other, each of the extended lines being formed by extending a center line, which connects a center of an X-ray source side of each of the plurality of opaque objects facing the X-ray source with a center of a detector side of each of the plurality of opaque objects facing the detector, toward the X-ray source, andwherein the grating is arranged so that a focused position of the grating at which the plurality of extended lines intersects each other and the X-ray source are arranged at positions different from each other. 2. The X-ray imaging apparatus according to claim 1, wherein the grating is arranged so that a position obtained by moving a position at which the X-ray source is located in a direction perpendicular to an optical axis corresponds to the focused position of the grating. 3. The X-ray imaging apparatus according to claim 1, wherein the grating is arranged so that a position obtained by rotating a position at which the X-ray source is located around one point on an optical axis corresponds to the focused position of the grating. 4. The X-ray imaging apparatus according to claim 1, whereinwhen an angle between the center line of the each of the plurality of opaque objects and X-rays entering each of the plurality of opaque object is θ,θ is greater than 0 degree and smaller than 20 degrees. 5. The X-ray imaging apparatus according to claim 4, wherein the θ is greater than 1 degree and smaller than 15 degrees. 6. The X-ray imaging apparatus according to claim 1, whereinX-rays entering the grating are shielded by a side surface of each of the plurality of opaque objects, so thata width of all X-rays divided by the grating on a surface of the grating facing the detector is smaller than a width of the transparent object on a surface of the grating facing the X-ray source. 7. An X-ray imaging apparatus comprising:an X-ray source;a grating configured to divide parallel X-rays irradiated from the X-ray source; anda detector configured to detect intensity of X-rays which are divided by the grating and pass through a sample,wherein the grating includes a plurality of transparent objects which pass the parallel X-rays and a plurality of opaque objects configured to shield the parallel X-rays, and an angle between a center line which connects a center of each side of each of the plurality of opaque objects facing the X-ray source and facing the detector, and X-rays entering the opaque object is greater than 0 degrees and smaller than 20 degrees, andwherein, when an aperture ratio of the grating is defined as a formula described below, the aperture ratio is greater than or equal to 5% and smaller than 50%:D =(Ga−t×tanθ)/(Ga+Gb)here, D is the aperture ratio, Ga is a width of the transparent object on a surface of the grating facing the X-ray source, t is a thickness of the grating, Gb is a width of the opaque object on a surface of the grating facing the X-ray source, and θ is an angle between the center line of the opaque object and X-rays entering the opaque object. 8. The X-ray imaging apparatus according to claim 7, wherein an angle between the center line and the X-rays entering the opaque object is greater than 1 degree and smaller than 15 degrees. 9. The X-ray imaging apparatus according to claim 1, whereinwhen an aperture ratio of the grating is defined as a formula described below, the aperture ratio is greater than or equal to 5% and smaller than 50%:D =(Ga−t×tanθ)/(Ga+Gb)here, D is the aperture ratio, Ga is a width of the transparent object on a surface of the grating facing the X-ray source, t is a thickness of the grating, Gb is a width of the opaque object on a surface of the grating facing the X-ray source, and θ is an angle between the center line of the opaque object and X-rays entering the opaque object. 10. The X-ray imaging apparatus according to claim 1, wherein X-ray beams are formed on the detector by the divide of the X-rays by the grating. 11. The X-ray imaging apparatus according to claim 1, wherein the sample is placed between the grating and the detector. 12. The X-ray imaging apparatus according to claim 10 further comprisinga calculation device configured to perform calculation based on a detection result of the detector, whereinthe calculation device calculates an amount of positional shift of the X-ray beams on the detector caused by the sample. 13. The X-ray imaging apparatus according to claim 1, wherein a width of the plurality of opaque objects is larger than a width of the plurality of transparent objects. 14. The X-ray imaging apparatus according to claim 7, wherein X-ray beams are formed on the detector by the divide of the X-rays by the grating. 15. The X-ray imaging apparatus according to claim 14, further comprisinga calculation device configured to perform calculation based on a detection result of the detector, whereinthe calculation device calculates an amount of positional shift of the X-ray beams on the detector caused by the sample. 16. The X-ray imaging apparatus according to claim 7, wherein a width of the plurality of opaque objects is larger than a width of the plurality of transparent objects. 17. The X-ray imaging apparatus according to claim 1, wherein the grating is a focused grid. 18. The X-ray imaging apparatus according to claim 1, wherein when an angle between the center line of the each of the plurality of opaque objects and X-rays entering each of the plurality of opaque object is θ,θ is greater than 0 degree. 19. The X-ray imaging apparatus according to claim 1, wherein the grating is two-dimensional grating.