X-ray source with non-planar voltage multiplier

Patent metadata

Field	Value
Publication number	US-10499484-B2
Application number	US-201816142334-A
Country	US
Kind code	B2
Filing date	Sep 26, 2018
Priority date	Nov 16, 2017
Publication date	Dec 3, 2019
Grant date	Dec 3, 2019

Abstract

In order to reduce the amount of electrical insulation needed for voltage isolation of large voltages generated by a voltage multiplier, the voltage multiplier can be shaped to smooth out electric field gradients. The voltage multiplier can comprise multiple sections, each section located in a different plane. The voltage multiplier can comprise a negative voltage multiplier and a positive voltage multiplier, each inclined at different angles with respect to each other. The voltage multiplier can include a curved shape.

First claim

What is claimed is:

1. An x-ray source comprising:
a voltage multiplier configured to multiply an input electrical voltage to produce an output bias voltage having an absolute value of ≥2 kV, the voltage multiplier comprising:
a low voltage section located in a first plane and a high voltage section located in a second plane;
the first plane and the second plane forming a V-shape with an angle of a channel of the V-shape being ≥60° and ≤170°;
the low voltage section configured to produce ≥1 kV absolute value of bias voltage and providing input electrical power to the high voltage section; and
the high voltage section configured to produce ≥1 kV absolute value of bias voltage and provide output electrical power to a high voltage apparatus at the output bias voltage;

an x-ray tube located in the channel of the V-shape; and
the voltage multiplier electrically coupled to the x-ray tube and configured to provide the output bias voltage to the x-ray tube.

2. The x-ray source of claim 1 , wherein an x-ray tube axis, extending from an electron emitter associated with a cathode to a target material associated with an anode of the x-ray tube, is aligned with the channel of the V-shape.

3. The x-ray source of claim 1 , further comprising:
a corona guard;
the corona guard including a curved profile wrapping at least partially around the voltage multiplier;
the corona guard having a material at a concave side of the curved profile with an electrical resistivity of ≥10 5 Ω*m; and
a voltage sensor electrically coupled to the output bias voltage and located on a convex side of the curved profile.

4. The x-ray source of claim 3 , wherein the curved profile wraps at least partially around a curved, cylindrical shape of the x-ray tube and is aligned with an x-ray tube axis, the x-ray tube axis extending from an electron emitter associated with a cathode to a target material associated with an anode of the x-ray tube.

5. The x-ray source of claim 1 , wherein:
the V-shape is a primary V-shape, the voltage multiplier is a negative voltage multiplier, the output bias voltage is a negative output bias voltage, the negative voltage multiplier is electrically coupled to a cathode of the x-ray tube and configured to provide the negative output bias voltage to the cathode, the low voltage section is a negative low voltage section, and the high voltage section is a negative high voltage section;
the x-ray source further comprises a positive voltage multiplier configured to multiply an input electrical voltage to produce a positive output bias voltage of ≥2 kV, the positive voltage multiplier comprising:
a positive low voltage section located in a third plane and a positive high voltage section located in a fourth plane;
the third plane and the fourth plane forming a secondary V-shape with an angle of a channel of the secondary V-shape being ≥60° and ≤170°;
the positive low voltage section configured to produce ≥1 kV of bias voltage and provide input electrical power to an input of the positive high voltage section; and
the positive high voltage section configured to produce ≥1 kV of bias voltage, electrically coupled to an anode of the x-ray tube, and configured to provide the positive output bias voltage to the anode.

6. The x-ray source of claim 5 , wherein an x-ray tube axis, extending from an electron emitter associated with the cathode to a target material associated with the anode, is aligned with the channel of the primary V-shape of the negative voltage multiplier and with the channel of the secondary V-shape of the positive voltage multiplier.

7. The x-ray source of claim 5 , wherein the negative output bias voltage and the positive output bias voltage are located on opposite sides of the x-ray tube.

8. The voltage multiplier of claim 1 , further comprising:
a middle voltage section electrically coupled between the low voltage section and the high voltage section;
the middle voltage section configured to produce 1 kV absolute value of bias voltage and provide input electrical power to the high voltage section;
the middle voltage section located in a seventh plane, the seventh plane being different from the first plane and the second plane; and
an angle between the seventh plane and the first plane and an angle between the seventh plane and the second plane, both located on a same side of the seventh plane, both have a value of ≥70° and ≤170°.

9. An x-ray source comprising:
a voltage multiplier including:
a negative voltage multiplier configured to multiply an input electrical voltage to produce a negative output bias voltage having a value of ≤−2 kV, the negative voltage multiplier having an end with a lowest absolute value of voltage, defining a negative low voltage end, and an end with a highest absolute value of voltage, defining a negative high voltage end;
a positive voltage multiplier configured to multiply an input electrical voltage to produce a positive output bias voltage having a value of 2 kV, the positive voltage multiplier having an end with a lowest voltage, defining a positive low voltage end, and an end with a highest voltage, defining a positive high voltage end; and
the negative voltage multiplier and the positive voltage multiplier inclined at different angles with respect to each other such that an end view of the voltage multipliers forms an X-shape by intersection of a plane of the negative voltage multiplier and a plane of the positive voltage multiplier;

an x-ray tube located in a channel of the X-shape;
the negative voltage multiplier: electrically coupled to a cathode of the x-ray tube; located closer than the positive voltage multiplier to the cathode; and configured to provide electrical power to the cathode at the negative output bias voltage; and
the positive voltage multiplier: electrically coupled to an anode of the x-ray tube; located closer than the negative voltage multiplier to the anode; and configured to provide electrical power to the anode at the positive output bias voltage.

10. The x-ray source of claim 9 , wherein an x-ray tube axis, extending from an electron emitter associated with a cathode to a target material associated with an anode of the x-ray tube, is aligned with the channel of the X-shape.

11. The voltage multiplier of claim 9 , wherein an angle of the channel of the X-shape is ≥15° and ≤170°.

12. The x-ray source of claim 9 , wherein the negative low voltage end is 2 times farther from the x-ray tube than the negative high voltage end; and the positive low voltage end is ≥2 times farther from the x-ray tube than the positive high voltage end.

13. The x-ray source of claim 9 , further comprising:
a corona guard;
the corona guard including a curved profile wrapping at least partially around the negative voltage multiplier and the positive voltage multiplier;
the corona guard having a material at a concave side of the curved profile with an electrical resistivity of ≥10 5 Ω*m;
a negative voltage sensor electrically coupled to the negative output bias voltage and located on a convex side of the curved profile; and
a positive voltage sensor electrically coupled to the positive output bias voltage and located on the convex side of the curved profile.

14. The x-ray source of claim 13 , wherein the negative voltage sensor and the positive voltage sensor wrap 180° of a 360° circumference around the cylindrical shape of the x-ray tube.

15. An x-ray source comprising:
a voltage multiplier configured to multiply an input electrical voltage to produce an output bias voltage having an absolute value of ≥2 kV, the voltage multiplier comprising:
a fir

Assignees

• Moxtek Inc

Inventors

• Miller Eric
• Hoffman David S
• Jones Vincent F

Classifications

• H05G1/06

  X-ray tube and at least part of the power supply apparatus being mounted within the same housing · CPC title

• H02M7/106 Primary

  With physical arrangement details · CPC title

• H05G1/10 Primary

  Power supply arrangements for feeding the X-ray tube {(supply circuits with converters in general H02M; supply circuits for emitters and amplifiers H04B1/16 - H04B1/1623)} · CPC title

• H01J35/025

  X-ray tubes with structurally associated circuit elements · CPC title