Multiradiation generation apparatus and radiation imaging system utilizing dual-purpose radiation sources

Patent metadata

Field	Value
Publication number	US-9408577-B2
Application number	US-201414189952-A
Country	US
Kind code	B2
Filing date	Feb 25, 2014
Priority date	Feb 26, 2013
Publication date	Aug 9, 2016
Grant date	Aug 9, 2016

Abstract

A multiradiation generation apparatus according to the present invention includes a plurality of radiation sources arranged in a row. Each of the radiation sources includes an electron source configured to emit electrons and a target unit configured to generate radiation upon receiving electrons emitted from the electron source. At least one of the radiation sources is a dual-purpose radiation source used for both tomosynthesis imaging and non-tomosynthesis imaging, and the other radiation sources are single-purpose radiation sources used only for tomosynthesis imaging.

First claim

What is claimed is:

1. A multiradiation generation apparatus comprising:
a plurality of radiation sources arranged in a row,
wherein at least one of the plurality of radiation sources is a dual-purpose radiation source and the remaining plurality of radiation sources are single-purpose radiation sources,
wherein the dual-purpose radiation source is used for both tomosynthesis imaging and non-tomosynthesis imaging, and the single-purpose radiation sources are used only for tomosynthesis imaging
wherein each of the plurality of radiation sources includes an electron source configured to emit electrons and a target unit configured to generate radiation upon receiving electrons emitted from the electron source,
wherein each of the plurality of radiation sources further includes a shield arranged around the corresponding target unit,
wherein the shield has a passage hole and an emission hole, and
wherein the passage hole or the emission hole of the shield of the dual-purpose radiation source has a smaller diameter at a place where the passage hole or the emission hole is in contact with the target unit than that of each of the passage holes or the emission holes of the shields of the single-purpose radiation sources.

2. The multiradiation generation apparatus according to claim 1 , wherein, when electrons are irradiated under the same conditions, an electron irradiated surface of the target unit of the dual-purpose radiation source is configured to have a smaller temperature increase than that of each of the target units of the single-purpose radiation sources.

3. The multiradiation generation apparatus according to claim 2 , wherein the target unit of the dual-purpose radiation source has higher heat release properties than those of each of the target units of the single-purpose radiation sources.

4. The multiradiation generation apparatus according to claim 2 ,
wherein the target unit includes a substrate and a target layer which is formed on a side of the substrate on the side facing the electron source, and
wherein the substrate of the target unit of the dual-purpose radiation source is thicker than the substrate of each of the target units of the single-purpose radiation sources.

5. The multiradiation generation apparatus according to claim 2 ,
wherein the target unit includes a substrate and a target layer which is formed on a side of the substrate on the side facing the electron source, and
wherein the substrate of the target unit of the dual-purpose radiation source has a larger diameter than that of each of the substrates of the target units of the single-purpose radiation sources.

6. The multiradiation generation apparatus according to claim 2 ,
wherein the target unit of the dual-purpose radiation source is arranged with an inclination with respect to a direction in which the electrons are caused to be incident, and
wherein each of the target units of the single-purpose radiation sources is arranged perpendicularly with respect to the direction in which the electrons are caused to be incident.

7. The multiradiation generation apparatus according to claim 1 ,
wherein the passage hole of the shield is arranged on the side of the electron source and passes the electrons, and
wherein the emission hole of the shield is arranged on the opposite side of the electron source and allows emission of radiation generated by the target unit to a predetermined region.

8. The multiradiation generation apparatus according to claim 7 , wherein the shield of the dual-purpose radiation source is thicker than each of the shields of the single-purpose radiation sources in a direction perpendicular to the row of the target units and a direction in which the electrons are caused to be incident.

9. The multiradiation generation apparatus according to claim 7 , wherein a heat-release fin is connected to the shield of the dual-purpose radiation source.

10. The multiradiation generation apparatus according to claim 7 , wherein the shields of the radiation sources are integrally formed.

11. A radiation imaging system comprising:
the multiradiation generation apparatus according to claim 1 ;
a radiation detection apparatus configured to detect radiation that has been emitted from the multiradiation generation apparatus and has passed through an object; and
a system control apparatus configured to perform cooperation control over the radiation generation apparatus and the radiation detection apparatus.

12. The radiation imaging system according to claim 11 , wherein the radiation imaging system has a tomosynthesis imaging mode in which radiation is sequentially emitted from the radiation sources arranged in a row, and a non-tomosynthesis imaging mode in which radiation is emitted only from the dual-purpose radiation source.

13. The radiation imaging system according to claim 12 , wherein the system control apparatus performs control so that a first acceleration voltage is applied between the electron source and the target unit of each of the radiation sources in the tomosynthesis imaging mode, and a second acceleration voltage different from the first acceleration voltage is applied between the electron source and the target unit of the dual-purpose radiation source in the non-tomosynthesis imaging mode.

14. A multi X-ray generation apparatus comprising:
a cathode array having a plurality of electron emitting sources each of which is aligned in a sequential manner;
an anode array having a shield member having a plurality of apertures corresponding to the electron emitting source and a plurality of targets each of which is secured to the corresponding aperture; and
a vacuum envelope having a cavity for storing the cathode array therein and an opening for securing the anode array,
wherein the plurality of targets includes a dual-purpose target used for both tomosynthesis imaging and non-tomosynthesis imaging and a plurality of single-purpose targets used only for tomosynthesis imaging, and
wherein a distance between a focal spot on the dual-purpose target and the shield member is shorter than a distance between a focal spot on any one of the plurality of single-purpose targets and the shield member such that a thermal transmittance from the dual-purpose target to the shield member is higher than a thermal transmittance from any one of the plurality of single-purpose targets to the shield member.

15. The multi X-ray generation apparatus according to claim 14 , wherein, when electrons are irradiated under the same conditions, an electron irradiated surface of the dual-purpose target is configured to have a smaller temperature increase than that of each of the single-purpose targets.

16. The multi X-ray generation apparatus according to claim 15 , wherein the dual-purpose target has higher heat release properties than those of each of the single-purpose targets.

17. The multi X-ray generation apparatus according to claim 15 ,
wherein the plurality of targets includes a substrate and a target layer which is formed on a side of the substrate on the side facing the electron emitting source, and
wherein the substrate of the dual-purpose target is thicker than the substrate of each of the single-purpose targets.

18. The multi X-ray generation apparatus according to claim 15 ,
wherein the plurality of targets includes a substrate and a target layer which is formed on a side of the substrate on the side facing the electron emitting source, and
wherein the substrate of the dual-purpose target has a larger diameter than that of each of the substrates of the single

Assignees

• Canon Kk

Inventors

• Tamura Miki
• Ueda Kazuyuki

Classifications

• H01J35/16

  Vessels; Containers; Shields associated therewith · CPC title

• H01J2235/166

  against electromagnetic radiation · CPC title

• H01J35/12

  Cooling non-rotary anodes · CPC title

• H01J2235/205

  Gettering · CPC title

• A61B6/025 Primary

  Tomosynthesis · CPC title