Phase contrast imaging computed tomography scanner
A grating based differential phase contrast imaging (DPCI) apparatus and acquisition technique whereby the system generates horizontal moiré fringes on a detector of the DPCI system by tilting at least one of the G1 and G2 gratings, and capturing images of an object including moving the object in a direction perpendicular to the lines of the moiré fringes.
1. A method comprising:
providing a DPCI system having an x-ray source and, in order along a z axis starting from the x-ray source, a G0 grating, a G1 grating, a G2 grating, and a digital detector;
aligning in parallel to a y axis, grating bars of the G0 grating, the G1 grating, and the G2 grating; and
generating moiré fringes on the detector, the moiré fringes aligned in a direction transverse to the y axis, including tilting about an x axis at least one of the G1 and G2 gratings of the system relative to each other,
wherein the x axis, the y axis and the z axis are perpendicular to each other.
2. The method of claim 1 , further comprising capturing images of an object positioned between the x-ray source and the G1 grating, including linearly translating the object in a direction parallel to the y axis.
3. The method of claim 2 , further comprising rotating the object about a rotation axis parallel to the y axis, the rotation axis coinciding with the object, to generate a helical scan of the object.
4. The method of claim 3 , further comprising using a slot scanning configuration of the DPCI system, wherein a length of each captured image is at least six times greater than its width.
5. A method comprising:
providing a DPCI system having an x-ray source and, in order along a z axis starting from the x-ray source, a G0 grating, a G1 grating, a G2 grating, and a digital detector;
aligning in parallel to a y axis, the grating bars of the G0 grating, the G1 grating, and the G2 grating; and
generating moiré fringes on the detector of the DPCI system, including tilting the G1 grating about an x axis,
wherein the x axis, the y axis and the z axis are perpendicular to each other.
6. The method of claim 5 , further comprising capturing images of an object positioned between the x-ray source and the G1 grating.
7. The method of claim 6 , further comprising linearly translating the object in a direction parallel to the y axis during the step of capturing images of the object.
8. The method of claim 7 , further comprising rotating the object about a rotation axis parallel to the y axis, the rotation axis coinciding with the object, during the step of capturing images of the object.
9. The method of claim 8 , further comprising using a slot scanning configuration of the DPCI system, wherein a length of each captured image is at least six times greater than its width.
10. A method comprising:
providing a DPCI system having an x-ray source and, in order along a z axis starting from the x-ray source, a G0 grating, a G1 grating, a G2 grating, and a digital detector;
aligning in parallel to a y axis, grating bars of the G0 grating, the G1 grating, and the G2 grating; and
generating moiré fringes on the detector of the DPCI system, including tilting the G2 grating about an x axis and not tilting the G1 grating,
wherein the x axis, the y axis and the z axis are perpendicular to each other.
11. The method of claim 10 , further comprising capturing images of an object positioned between the x-ray source and the G1 grating.
12. The method of claim 11 , further comprising linearly translating the object in a direction parallel to the y axis during the step of capturing images of the object.
13. The method of claim 12 , further comprising rotating the object about a rotation axis parallel to the y axis, the rotation axis coinciding with the object, during the step of capturing images of the object.
14. The method of claim 13 , further comprising using a slot scanning configuration of the DPCI system, wherein a length of each captured image is at least six times greater than its width.