Methods, systems, and computer program products for binary multiplexing x-ray radiography

• US 8,189,893 B2
• Filed: 05/21/2007
• Issued: 05/29/2012
• Est. Priority Date: 05/19/2006
• Status: Active Grant

• Current Assignee: North Carolina State University (University of North Carolina System), University of North Carolina At Chapel Hill (University of North Carolina System)
• Original Assignee: North Carolina State University (University of North Carolina System), University of North Carolina At Chapel Hill (University of North Carolina System)
• Inventors: Lu, Jianping, Zhou, Otto Z., Lalush, David, Zhang, Jian
• Primary Examiner(s): CHANG, JON CARLTON
• Application Number:
  US11/804,897
• Publication Number:
  US 20080069420A1
• Time in Patent Office: 1,835 Days
• Field of Search: 382/131, 382/132, 378/4, 378/9, 378/12, 378/16
• US Class Current: 382/131
• CPC Class Codes: A61B 6/00 Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment instruments measuring radiation intensity for application in the field of nuclear medicine, e.g. in vivo counting, G01T1/161; apparatus for taking X-ray photographs G03B42/02
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/4021 involving movement of the focal spot
• CPC Class Codes: A61B 6/405 Source units specially adapted to modify characteristics of the beam during the data acquisition process A61B6/4021, A61B6/4035 take precedence
• CPC Class Codes: A61B 6/482 involving multiple energy imaging
• CPC Class Codes: G01N 23/00 Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
• CPC Class Codes: G06T 11/005 Specific pre-processing for tomographic reconstruction, e.g. calibration, source positioning, rebinning, scatter correction, retrospective gating
• CPC Class Codes: G06T 2211/408 Dual energy
• CPC Class Codes: H01J 2235/062 Cold cathodes
• CPC Class Codes: H01J 2235/068 Multi-cathode assembly
• CPC Class Codes: H01J 35/065 Field emission, photo emission or secondary emission cathodes
• CPC Class Codes: H05G 1/52 Target size or shape; Direction of electron beam, e.g. in tubes with one anode and more than one cathode

Abstract

Methods, systems, and computer program products for binary multiplexing x-ray radiography are disclosed. According to one aspect, the subject matter described herein can include irradiating an object with composite x-ray beams including signals based on a predetermined binary transform. Further, the subject matter described herein can include detecting x-ray intensities associated with the signals of the composite x-ray beams. An inverse binary transform can be applied to the detected x-ray intensities associated with the signals of the composite x-ray beams to recover the signals of the composite x-ray beams.

Claims

1. A method of binary multiplexing x-ray radiography, the method comprising:

irradiating an object from a plurality of different locations with N composite x-ray beams including signals from N different x-ray sources based on a predetermined binary transform in which each of the different x-ray sources is turned on at least (N+1)/2 times;

detecting x-ray intensities associated with the signals of the composite x-ray beams that have passed through the object; and

applying an inverse binary transform to the detected x-ray intensities associated with the signals of the composite x-ray beams to recover the signals from the different x-ray sources.

2. The method of claim 1 wherein irradiating an object comprises irradiating the object with the composite x-ray beams generated by a plurality of x-ray sources.

3. The method of claim 1 wherein the x-ray sources comprise multi beam field emission x-ray sources.

4. The method of claim 1 wherein irradiating an object comprises irradiating the object with a predetermined pattern of the composite x-ray beams.

5. The method of claim 1 wherein irradiating an object comprises irradiating the object with composite x-ray beams including signals based on a predetermined Hadamard binary transform.

6. The method of claim 1 wherein irradiating the object with composite x-ray beams comprises irradiating the object with a plurality of monochromatic x-ray beams.

7. The method of claim 1 irradiating the object with a plurality of x-ray beams having different ray energies.

8. The method of claim 1 wherein detecting x-ray intensities comprises detecting the x-ray intensities with an one dimensional array or two dimension array of x-ray detectors.

9. The method of claim 8 wherein the x-ray detector is configured to record the x-ray intensities associated with the signals of the composite x-ray beams at a fast frame rate.

10. A binary multiplexing x-ray radiography system comprising:

a plurality of x-ray sources configured to irradiate an object from a plurality of different locations with N composite x-ray beams including signals from N individual x-ray beams based on a predetermined binary transform in which each of the individual x-ray beams is turned on at least (N+1)/2 times;

an x-ray detector configured to detect x-ray intensities associated with the signals of the composite x-ray beams that have passed through the object; and

an inverse binary transform function processor configured to apply an inverse binary transform to the detected x-ray intensities associated with the signals of the composite x-ray beams to recover the signals from individual x-ray beams.

11. The system of claim 10 wherein the x-ray sources comprise a plurality of field emission x-ray sources.

12. The system of claim 10 wherein the x-ray sources are configured to irradiate the object with a predetermined pattern of the composite x-ray beams.

13. The system of claim 10 wherein the x-ray sources are configured to irradiate the object with composite x-ray beams including signals based on a predetermined Hadamard binary transform.

14. The system of claim 10 wherein the plurality of x-ray sources are configured to irradiate the object with a plurality of monochromatic x-ray beams.

15. The system of claim 10 wherein irradiating the object with a plurality of x-ray beams with different energies.

16. The system of claim 10 wherein the x-ray detector comprises an array of one dimensional or two dimensional detector elements.

17. The system of claim 10 wherein the x-ray detector is configured to record the x-ray intensities associated with the signals of the composite x-ray beams at a fast frame rate.

18. A computer program product comprising computer-executable instructions embodied in a non-transitory computer-readable medium for directing a computer to perform steps comprising:

irradiating an object from a plurality of different locations with N composite x-ray beams including N individual signals based on a predetermined binary transform in which each of the individual signals is turned on at least (N+1)/2 times;

detecting x-ray intensities associated with the signals of the composite x-ray beams that have passed through the object; and

applying an inverse binary transform to the detected x-ray intensities associated with the signals of the composite x-ray beams to recover the signals from individual x-ray beams.

19. A binary multiplexing computed tomography x-ray imaging system comprising:

a plurality of x-ray sources configured to irradiate an object with N composite x-ray beams including signals from N individual x-ray beams based on a predetermined binary transform in which each of the individual x-ray beams is turned on at least (N+1)/2 times;

an x-ray detector configured to detect x-ray intensities associated with the signals of the composite x-ray beams;

an object stage positioned between the plurality of x-ray sources and the x-ray detector;

an electronic controller and a first computer program that enable the system to collect a sequence of composite images of the object corresponding to the x-ray intensities;

a second computer program that applies an inverse binary transform to the composite images to obtain the projection images of the object from the individual x-ray beams; and

an image reconstruction program to generate computed tomography images of the object.

20. The device of claim 19 wherein the binary transform is a Hadamard binary transform.

21. The device of claim 19 comprising an anti-scattering device configured to minimize scattered x-ray signals collected by the x-ray detector.

22. The device of claim 19 comprising a third computer program configured to analyze each composite x-ray image and configured to remove scattered x-ray intensities from the multiple x-ray beams based on an algorithm.

23. The device of claim 19 wherein the multiple x-ray emitting pixels are one of enclosed in one vacuum enclosure, enclosed in several vacuum enclosures wherein each vacuum enclosure contains a plurality of x-ray pixels, and enclosed in several vacuum enclosures wherein each vacuum enclosure encloses a single x-ray pixel.

24. The device of claim 19 wherein the x-ray source is an electron field emission multi-pixel x-ray source.