In-line x-ray focusing optics used for manipulation of x-rays in medical transmission radiography

Patent metadata

Field	Value
Publication number	US-11033243-B2
Application number	US-201916590645-A
Country	US
Kind code	B2
Filing date	Oct 2, 2019
Priority date	Apr 18, 2019
Publication date	Jun 15, 2021
Grant date	Jun 15, 2021

Abstract

There is provided an arrangement including an x-ray detector arranged in conjunction with in-line x-ray focusing optics configured for manipulation of x-rays in medical transmission radiography, wherein the in-line x-ray optics includes an array of lenses, in which the lenses cover parts of, or the entire, field of view, and in which the x-ray detector is a photon-counting detector. Furthermore, the x-ray detector is an energy-resolving detector and chromatic aberration of the lens array and/or limited coherence of the source is compensated for by the energy resolution of the energy-resolving detector, and/or the x-ray detector is a depth-resolving detector and chromatic aberration of the lens array and/or limited coherence of the source is compensated for by depth resolution or volumetric resolution in the detector.

First claim

The invention claimed is:

1. An arrangement comprising an x-ray detector arranged in conjunction with in-line x-ray focusing optics configured for manipulation of x-rays in medical transmission radiography, wherein the in-line x-ray optics comprises an array of lenses, in which the lenses cover parts of, or the entire, field of view, and in which the x-ray detector is a photon-counting detector,
wherein the x-ray detector is a depth-resolving detector and chromatic aberration of the lens array and/or limited coherence of the source is compensated for by depth resolution or volumetric resolution in the x-ray detector.

2. The arrangement according to claim 1 , which is configured to separate primary photons from scattered photons such that primary photons, which are parallel or near parallel, are concentrated to a focus, whereas scattered photons with a wider angular distribution are not concentrated to a focus.

3. The arrangement according to claim 2 , in which the x-ray detector is a pixelated detector and the separation between primary and scattered photons is conducted with the pixelated detector, said detector having two or more pixels covering each lens in the lens array.

4. The arrangement according to claim 2 , in which scattered photons are blocked by means of an anti-scatter grid in addition to the lens array.

5. The arrangement according to claim 2 , in which scattered photons are blocked by means of a pin hole or a slit upstream of the x-ray detector.

6. The arrangement according to claim 1 , in which the arrangement is configured for operation with raytracing methods used in conjunction with energy and/or depth resolution in the x-ray detector to increase spatial resolution of the arrangement.

7. The arrangement according to claim 1 , in which the arrangement is configured to estimate or enable estimation of the local phase gradient of the imaged object in one or two dimensions at each lens from the detected location of the focal spot relative to the optical axis of the lens.

8. The arrangement according to claim 1 , in which the arrangement is configured to obtain or enable the obtaining of information on small-angle scattering in the object from the broadening of the focal spot or from the total signal outside of the focal spot peak.

9. The arrangement according to claim 7 , in which the arrangement is configured to determine or enable determination of the location and/or size of the focal spot of each lens by scanning a grating or a number of pin holes in front of the x-ray detector.

10. The arrangement according to claim 7 , in which the x-ray detector is a high-resolution detector and the arrangement is configured to determine or enable determination of the location and/or size of the focal spot of each lens by detecting the signal with the high-resolution detector, said detector having a resolution higher than the deviation of the focal spot from the focal spot's nominal size and position.

11. The arrangement according to claim 7 , in which the arrangement is configured to determine or enable determination of the location and/or size of the focal spot to a higher resolution than the detector, where two or more detector elements of the x-ray detector sample the distribution of focused photons reaching the x-ray detector.

12. The arrangement according to claim 7 , in which the arrangement comprises a grating or a number of pin holes placed in front of the source, such that each lens in the lens array is operable for imaging a number of spots.

13. The arrangement according to claim 1 , which is configured for breast imaging.

14. The arrangement according to claim 1 , which is configured for computed tomography.

15. The arrangement according to claim 1 , which is configured for fluoroscopic imaging.

16. The arrangement according to claim 1 , which is configured to simultaneously acquire at least two of transmission, phase-contrast and dark-field images.

17. The arrangement according to claim 1 , in which the lens array focuses in one dimension so that the focus is a line.

18. The arrangement according to claim 1 , in which the lens array focuses in two dimensions so that the focus is a spot.

19. The arrangement according to claim 1 , in which the lens array is placed between the object and the x-ray detector.

20. The arrangement according to claim 1 , in which the lens array is placed between the source and the object.

21. The arrangement according to claim 1 , in which the energy and/or depth resolution of the photon-counting detector is used to sort photons into categories, which are treated differently depending on the energy and/or depth of interaction.

22. The arrangement according to claim 21 , in which the energy and/or depth resolution of the photon-counting detector is used for weighting of photons such that photons carrying more information are assigned a higher weight compared to photons carrying less information.

23. The arrangement according to claim 1 , in which the arrangement comprises processing circuitry configured to perform signal and/or data processing.

24. An x-ray imaging system and/or a system for medical x-ray imaging comprising an arrangement according to claim 1 .

25. The x-ray imaging system of claim 24 , in which the x-ray detector is an energy-resolving detector and the system is configured to decompose the focus into energy-resolved components.

26. The x-ray imaging system of claim 24 , in which the x-ray detector is a depth-resolving detector and the x-ray imaging system is configured to compensate for the chromatic aberration by using the depth resolution or volumetric resolution of the x-ray detector, either independently or in conjunction with energy resolution of the x-ray detector.

27. The x-ray imaging system of claim 24 , in which the x-ray imaging system is configured for performing raytracing in conjunction with energy and/or depth resolution in the detector to increase spatial resolution.

28. The x-ray imaging system of claim 24 , in which the x-ray imaging system comprises processing circuitry configured to perform signal and/or data processing.

29. The arrangement according to claim 1 , wherein the x-ray detector is an energy-resolving detector and chromatic aberration of the lens array and/or limited coherence of the source is compensated for by the energy resolution of the energy-resolving detector.

Assignees

• Prismatic Sensors Ab

Inventors

• Fredenberg Erik
• Loberg Johannes
• Danielsson Mats

Classifications

• A61B6/502

  for diagnosis of breast, i.e. mammography · CPC title

• A61B6/487

  involving fluoroscopy · CPC title

• A61B6/4021 Primary

  involving movement of the focal spot · CPC title

• A61B6/484

  involving phase contrast X-ray imaging · CPC title

• A61B6/4241 Primary

  using energy resolving detectors, e.g. photon counting · CPC title