X-ray tomography device

Patent metadata

Field	Value
Publication number	US-9841388-B2
Application number	US-201214123018-A
Country	US
Kind code	B2
Filing date	Jun 1, 2012
Priority date	Jun 1, 2011
Publication date	Dec 12, 2017
Grant date	Dec 12, 2017

Abstract

An X-ray tomography device for providing a 3D image of a sample comprising a X-ray source, a cell, a photon detector and a processing unit. The processing unit computes the 3D tomography image on the basis of the acquired images corresponding to a plurality of cell angles. The cell is positioned so as the photon detector senses mainly photons coming from the sample inside the cell, and the photon detector is overexposed to cancel pixels corresponding to photons not coming from the sample.

First claim

The invention claimed is:

1. An X-ray tomography device for providing a 3D tomography image of a sample, said device comprising:
a X-ray source emitting a photon beam in the direction of a beam axis,
a cell adapted to include a porous sample to be imaged, said cell being situated inside the photon beam and being able to rotate about a cell angle around a cell axis that is substantially perpendicular to the beam axis, and being adapted to enable the porous sample to be flooded by at least one fluid,
a photon detector receiving a transmitted photon beam that is transmitted through said cell, said photon detector providing at least one acquired image for each angle of a plurality of cell angles, and
a processor that computes the 3D tomography image on the basis of the acquired images corresponding to the plurality of cell angles,
wherein
the X-ray tomography device further comprises a mean for positioning the cell inside the photon beam so as each acquired image produced by the photon detector comprises at least 70% of pixels corresponding to the sample,
the processor controls an exposure length of time of the photon detector in the photon beam for each acquired image so as the exposure length of time is higher than a first time limit and lower than a second time limit, said first time limit being determined so as the pixels not corresponding to the sample are overexposed, and the second time limit being determined so as the pixels corresponding to the sample are not overexposed, and
the processor computes the 3D tomography image for a region of interest with the non overexposed pixels and with the overexposed pixels.

2. The X-ray tomography device according to claim 1 , wherein the cell comprises an outer casing made of a material having an X-ray transmission higher than 80%.

3. The X-ray tomography device according to claim 1 , wherein the cell comprises an outer casing being able to withstand to a pressure higher than 300 bars.

4. The X-ray tomography device according to claim 1 , wherein the cell comprises an outer casing being able to withstand to a temperature higher than 300° C.

5. The X-ray tomography device according to claim 1 , wherein the X-ray source is a monochromatic source, and preferably a compact light source using a collision between a laser beam and an opposing electron beam.

6. The X-ray tomography device according to claim 1 , wherein the processor is computing the 3D tomography image during a time period lower than an acquisition length of time used for producing the acquired images corresponding to all the images in the plurality of cell angles.

7. The X-ray tomography device according to claim 1 , wherein the cell has a size comprised in the range of 0.3 cm to 20 cm.

8. The X-ray tomography device according to claim 1 , wherein the casing of the cell is made of a material comprising beryllium, beryllium alloy, or a carbon-carbon composite.

9. The X-ray tomography device according to claim 1 , wherein the photon detector comprises a CCD of at least ten megapixels.

10. The X-ray tomography device according to claim 1 , further comprising a grating based interferometer situated between the cell and the photon detector.

11. The X-ray tomography device according to claim 1 , further comprising a microscope situated between the cell and the photon detector.

12. The X-ray tomography device according to claim 3 , wherein the outer casing is able to withstand to a pressure up to 1000 bars.

13. The X-ray tomography device according to claim 4 , wherein the outer casing is able to withstand to a temperature up to 650° C.

14. The X-ray tomography device according to claim 5 , wherein the X-ray source is a compact light source using a collision between a laser beam and an opposing electron beam.

15. The X-ray tomography device according to claim 1 , wherein the cell has a size comprised in the range of 0.6 cm to 10 cm.

16. A method for providing a 3D tomography image of a sample from an X-ray tomography device, said method comprising:
emitting a photon beam from an X-ray source in the direction of a beam axis at a cell adapted to include a porous sample to be imaged,
positioning the cell inside the photon beam so that each acquired image produced by a photon detector comprises at least 70% of pixels corresponding to the sample
rotating the cell about a cell angle around a cell axis that is substantially perpendicular to the beam axis,
flooding the cell with at least one fluid,
receiving a transmitted photon beam by the photon detector, said photon beam transmitted through said cell,
providing said photon detector with at least one acquired image for each angle of a plurality of cell angles, and
processing 3D tomography image on the basis of the acquired images corresponding to the plurality of cell angles,
controlling an exposure length of time of the photon detector in the photon beam for each acquired image so as the exposure length of time is higher than a first time limit and lower than a second time limit, said first time limit being determined so as the pixels not corresponding to the sample are overexposed, and the second time limit being determined so as the pixels corresponding to the sample are not overexposed, and
computing the 3D tomography image for a region of interest with the non overexposed pixels and with the overexposed pixels.

17. The method according to claim 16 , wherein computing the 3D tomography image occurs during a time period lower than an acquisition length of time used for producing the acquired images corresponding to all the images in the plurality of cell angles.

18. The method according to claim 16 further comprising disposing a grating based interferometer between the cell and the photon detector.

19. The method according to claim 16 , further comprising disposing a microscope between the cell and the photon detector.

20. The method according to claim 16 , wherein the X-ray source is a compact light source using a collision between a laser beam and an opposing electron beam.

Assignees

• Creux Patrice
• Hamon Gérald
• Total Sa
• Univ De Pau Et Des Pays De L'Adour

Inventors

• Creux Patrice
• Hamon Gérald

Classifications

• G01N23/046 Primary

  using tomography, e.g. computed tomography [CT] · CPC title

• G01N2223/419

  computed tomograph · CPC title