X-ray source assembly

• US 9,666,322 B2
• Filed: 12/10/2014
• Issued: 05/30/2017
• Est. Priority Date: 02/23/2014
• Status: Active Grant

• Current Assignee: Bruker Technologies Ltd. (Bruker Corporation)
• Original Assignee: Bruker JV Israel, Ltd. (Bruker Corporation)
• Inventors: Mazor, Isaac, Wormington, Matthew, Peled, Asher, Brandt, Alex
• Primary Examiner(s): Song, Hoon
• Application Number:
  US14/565,474
• Publication Number:
  US 20150243469A1
• Time in Patent Office: 902 Days
• CPC Class Codes: G21K 1/06 using diffraction, refraction or reflection, e.g. monochromators G21K1/10, G21K7/00 take precedence
• CPC Class Codes: H01J 35/147 Spot size control
• 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

An apparatus includes an X-ray tube, X-ray optics, one or more coils and control circuitry. The X-ray tube is configured to direct an electron beam onto an anode so as to emit an X-ray beam. The X-ray optics which configured to receive the X-ray beam emitted from the X-ray tube and to direct the X-ray beam onto a target. The coils are configured to steer the electron beam in the X-ray tube using electrical currents flowing through the coils. The control circuitry is configured to compensate for misalignment between the X-ray tube and the X-ray optics by analyzing the X-ray beam output by the X-ray optics, and setting the electrical currents based on the analyzed X-ray beam.

Claims

1. Apparatus, comprising:

an X-ray tube, which comprises an X-ray window and is configured to direct an electron beam onto an anode so as to emit an X-ray beam through the X-ray window;

X-ray optics, which are mounted externally to the X-ray tube with a mechanical misalignment relative to the X-ray tube, and which are configured to receive the X-ray beam emitted from the X-ray tube through the X-ray window, and to direct the X-ray beam onto a target;

one or more coils, which are configured to steer the electron beam in the X-ray tube using electrical currents flowing through the coils; and

control circuitry, which is configured to;

determine, based on the X-ray beam output by the X-ray optics, respective values of the electrical currents that, when flowing in the coils, steer the electron beam to a region of the anode that causes the X-ray beam to compensate for the mechanical misalignment between the X-ray tube and the X-ray optics; and

set the electrical currents to the determined values.

2. The apparatus according to claim 1, wherein the control circuitry is configured to set the electrical currents to be constant.

3. The apparatus according to claim 1, wherein the control circuitry is configured to set the electrical currents adaptively based on the X-ray beam.

4. The apparatus according to claim 1, wherein the target comprises a detector comprised in the control circuitry, and wherein the control circuitry further comprises a processor configured to analyze an output of the detector and to set the electrical currents depending on the output.

5. The apparatus according to claim 1, wherein the control circuitry is configured to estimate a deviation of an actual characteristic of the emitted X-ray beam from a specified characteristic, and to set the electrical currents depending on the deviation.

6. The apparatus according to claim 5, wherein the actual and specified characteristics comprise at least one type of characteristic selected from a group of types consisting of a beam intensity, a beam spot size, and an intensity distribution across a beam spot.

7. The apparatus according to claim 1, wherein, in addition to compensating for the misalignment, the control circuitry is configured to optimize a characteristic of the X-ray beam by setting the electrical currents.

8. The apparatus according to claim 1, wherein the X-ray tube comprises an integrated magnetic shield, which is configured to protect the electron beam from magnetic fields external to the X-ray tube.

9. A method, comprising:

in an X-ray tube, which comprises an X-ray window, directing an electron beam onto an anode so as to emit an X-ray beam through the X-ray window;

receiving the X-ray beam emitted from the X-ray tube through the X-ray window, and directing the X-ray beam by X-ray optics, which are mounted externally to the X-ray tube with a mechanical misalignment relative to the X-ray tube, onto a target;

steering the electron beam in the X-ray tube using electrical currents flowing through coils surrounding the X-ray tube; and

determining, based on the X-ray beam output from the X-ray optics, respective values of the electrical currents that, when flowing in the coils, steer the electron beam to a region of the anode that causes the X-ray beam to compensate for the mechanical misalignment between the X-ray tube and the X-ray optics, and setting the electrical currents to the determined values.

10. The method according to claim 9, wherein setting the electrical currents comprises setting the electrical currents to be constant.

11. The method according to claim 9, wherein setting the electrical currents comprises setting the electrical currents adaptively based on the X-ray beam.

12. The method according to claim 9, wherein compensating for the misalignment comprises detecting the X-ray beam output by the X-ray optics using a detector, analyzing an output of the detector, and setting the electrical currents depending on the output.

13. The method according to claim 9, wherein determining the respective values comprises estimating a deviation of an actual characteristic of the emitted X-ray beam from a specified characteristic, and setting the electrical currents depending on the deviation.

14. The method according to claim 13, wherein the actual and specified characteristics comprise at least one type of characteristic selected from a group of types consisting of a beam intensity, a beam spot size, and an intensity distribution across a beam spot.

15. The method according to claim 9, and comprising, in addition to compensating for the misalignment, optimizing a characteristic of the X-ray beam by setting the electrical currents.

16. The method according to claim 9, and comprising protecting the electron beam from magnetic fields external to the X-ray tube by applying an integrated magnetic shield.