Apparatus and method to facilitate dynamically adjusting radiation intensity for imaging purposes

• US 7,991,117 B2
• Filed: 01/13/2009
• Issued: 08/02/2011
• Est. Priority Date: 01/13/2009
• Status: Active Grant

• Current Assignee: Varex Imaging Corporation
• Original Assignee: Varian Medical Systems Incorporated (Siemens AG)
• Inventors: Wilson, Zane J., Chen, Gongyin, Drubka, Robert Edward
• Primary Examiner(s): Yun; Jurie
• Application Number:
  US12/352,974
• Publication Number:
  US 20100177873A1
• Time in Patent Office: 931 Days
• Field of Search: 378/62, 378/95, 378/98.7, 378108-113, 378/138, 378150-153, 378/162
• US Class Current: 378/95
• CPC Class Codes: G01V 5/22 Active interrogation, i.e. by irradiating objects or goods using external radiation sources, e.g. using gamma rays or cosmic rays

Abstract

An x-ray-based radiation imaging apparatus (200) for use in imaging an object (201) can comprise a source of x-rays (202) having an output radiation intensity control input and a radiation intensity controller (207) operably coupled thereto. This radiation intensity controller can have a control output (209, 210) that is operably coupled to the output radiation intensity control input and an object information input (209). So configured, the radiation intensity controller can dynamically adjust radiation intensity as output by the source of x-rays as a function of information regarding the object itself.

Claims

1. An x-ray-based radiation imaging apparatus for use in imaging an object, the apparatus comprising:

a source of x-rays having an output radiation intensity control input, wherein the source of x-rays comprises;

an accelerator;

a radio frequency source having a radio frequency output operably coupled to feed the accelerator;

a particle source having a particle output operably coupled to the accelerator;

a radiation intensity controller having;

a control output that is operably coupled to the output radiation intensity control input; and

an object information input;

wherein the radiation intensity controller is configured to dynamically adjust radiation intensity as output by the source of x-rays as a function of information regarding the object.

2. The x-ray-based radiation imaging apparatus of claim 1 wherein:

the radiation intensity controller is configured to dynamically adjust radiation intensity as output by the source of x-rays as a function of information regarding the object by dynamically modifying a relative duration of providing particles to the accelerator from the particle source.

3. The x-ray-based radiation imaging apparatus of claim 2 wherein the particle source is configured to dynamically modify the relative duration of providing particles to the accelerator from the particle source by temporally shifting when a pulse of particles is provided by the particle source to the accelerator.

4. The x-ray-based radiation imaging apparatus of claim 2 wherein the particle source is configured to dynamically modify the relative duration of providing particles to the accelerator from the particle source by dynamically modifying a length of a pulse of particles as is provided by the particle source to the accelerator.

5. The x-ray-based radiation imaging apparatus of claim 2 wherein the radiation intensity controller is configured to dynamically adjust the radiation intensity while maintaining amplitudes of the radio frequency output and the particle output substantially stable.

6. The x-ray-based radiation imaging apparatus of claim 1 wherein the object information input is configured to receive x-ray-based information regarding the object.

7. The x-ray-based radiation imaging apparatus of claim 6 wherein the x-ray-based information regarding the object comprises information gleaned from a current in-process scan of the object.

8. The x-ray-based radiation imaging apparatus of claim 7 wherein the radiation intensity controller is configured to dynamically adjust the radiation intensity by:

tending to increase the radiation intensity, when possible, when the x-ray-based information corresponds to a portion of the object that comprises high attenuation material; and

tending to decrease the radiation intensity, when possible, when the x-ray-based information corresponds to a portion of the object that comprises low attenuation material.

9. The x-ray-based radiation imaging apparatus of claim 1 further comprising:

a selectively variable beam attenuator that is disposed between the source of x-rays and the object, wherein the selectively variable beam attenuator has a beam attenuator control input that is operably coupled to the radiation intensity controller;

and wherein the radiation intensity controller is configured to dynamically adjust radiation intensity as passes through the selectively variable beam attenuator as a function of information regarding the object.

10. The x-ray-based radiation imaging apparatus of claim 9 wherein the selectively variable beam attenuator comprises a plurality of individually selectable and automatically movable radiation-attenuating blocks.

11. A method for use in imaging an object, the method comprising:

providing a source of x-rays having an output radiation intensity control input, the source of x-rays comprising;

an accelerator;

a radio frequency source having a radio frequency output operably coupled to feed the accelerator; and

a particle source having a particle output operably coupled to the accelerator;

providing a radiation intensity controller having;

a control output that is operably coupled to the output radiation intensity control input; and

an object information input;

using the radiation intensity controller to dynamically adjust radiation intensity as output by the source of x-rays as a function of information regarding the object.

12. The method of claim 11 wherein:

using the radiation intensity controller to dynamically adjust radiation intensity as output by the source of x-rays as a function of information regarding the object comprises dynamically modifying a relative duration of providing particles to the accelerator from the particle source.

13. The method of claim 12 wherein using the particle source to dynamically modify the relative duration of providing particles to the accelerator from the particle source comprises temporally shifting when a pulse of particles is provided by the particle source to the accelerator.

14. The method of claim 12 wherein using the particle source to dynamically modify the relative duration of providing particles to the accelerator from the particle source comprises dynamically modifying a length of a pulse of particles as is provided by the particle source to the accelerator.

15. The method of claim 12 wherein using the radiation intensity controller comprises dynamically adjusting the radiation intensity while maintaining amplitudes of the radio frequency output and the particle output substantially stable.

16. The method of claim 11 wherein the object information input is configured to receive x-ray-based information regarding the object.

17. The method of claim 16 wherein the x-ray-based information regarding the object comprises information gleaned from a current in-process scan of the object.

18. The method of claim 17 wherein using the radiation intensity controller to dynamically adjust the radiation intensity comprises:

tending to increase the radiation intensity, when possible, when the x-ray-based information corresponds to a portion of the object that comprises high attenuation material; and

tending to decrease the radiation intensity, when possible, when the x-ray-based information corresponds to a portion of the object that comprises low attenuation material.

19. The method of claim 11 further comprising:

providing a selectively variable beam attenuator between the source of x-rays and the object, wherein the selectively variable beam attenuator has a beam attenuator control input that is operably coupled to the radiation intensity controller;

and wherein using the radiation intensity controller further comprises dynamically adjusting radiation intensity as passes through the selectively variable beam attenuator as a function of information regarding the object.

20. The method of claim 19 wherein dynamically adjusting radiation intensity as passes through the selectively variable beam attenuator comprises adjusting selected ones of a plurality of individually selectable and automatically movable radiation-attenuating blocks.