Extended multi-spot computed tomography x-ray source
View Patent ↗Systems and methods for obtaining multi-slice images having a total thickness of up to about 160 mm or more in a single gantry rotation in computed tomography or volume computed tomography are described. One embodiment comprises an extended, multi-spot x-ray source for computed tomography or volume computed tomography imaging, comprising: an electron gun capable of producing a plurality of electron beams, each electron beam focused at a predetermined distance and aimed in a predetermined direction; and a plurality of targets positioned to receive the electron beams and generate x-rays in response thereto, each target comprising a predetermined focal spot thereon, wherein each electron beam is synchronized to strike, at an appropriate time, a predetermined target comprising a predetermined focal spot thereon.
1. An extended multi-spot x-ray source for computed tomography or volume computed tomography imaging, comprising:
an electron gun for producing a plurality of electron beams, each electron beam focused at a predetermined distance and aimed in a predetermined direction;
a plurality of targets positioned to receive the electron beams and generate x-rays in response thereto, each target comprising a predetermined focal spot thereon, and at least one target configured to let electron beams pass therethrough and strike another target at predetermined intervals; and
means for synchronizing each electron beam to strike, at a predetermined time, a predetermined target comprising a predetermined focal spot thereon wherein at least one target comprises a cut-out section that allows electron beams to pass therethrough and strike another target at predetermined intervals.
2. The x-ray source of claim 1 , wherein each target comprises a different focal spot thereon.
3. The x-ray source of claim 1 , wherein each electron beam is focused at a different distance.
4. The x-ray source of claim 1 , wherein each electron beam is aimed in a different direction.
5. The x-ray source of claim 1 , wherein each electron beam strikes a different target having the appropriate focal spot thereon.
6. The x-ray source of claim 1 , wherein the plurality of targets rotate about an axis of rotation.
7. The x-ray source of claim 1 , wherein a single electron beam, focused at a predetermined distance, strikes only one target, comprising a matching predetermined focal spot thereon, at a time.
8. The x-ray source of claim 1 , wherein adjusting an accelerating voltage placed on the electron gun accomplishes at least one of: focusing at least one electron beam, and changing electron beam properties.
9. The x-ray source of claim 1 , wherein multi-slice images having a total thickness of up to about 160 mm can be obtained in a single gantry rotation.
10. The x-ray source of claim 1 , further comprising:
a sensing device for identifying a rotational position of the targets.
11. The x-ray source of claim 10 , wherein the sensing device comprises:
a magnetic material disposed on a rotor; and
a magnetic pick-up device disposed in close proximity to the magnetic material; wherein, when the rotor spins around its axis of rotation, the magnetic pick-up device obtains a voltage or current signal as the magnetic material passes thereby, and then the magnetic pick-up device transmits an appropriately treated and amplified signal to the electron gun to do at least one of: change electron beam focusing parameters, and make deflection corrections.
12. The x-ray source of claim 1 , wherein adjusting a focal bias voltage placed on the electron gun accomplishes at least one of: focusing at least one electron beam, and changing electron beam properties.
13. A method for obtaining thick multi-slice images in a single gantry rotation in computed tomography or volume computed tomography, the method comprising:
providing an electron gun for producing a plurality of electron beams, each electron beam focused at a predetermined distance and aimed in a predetermined direction;
providing a plurality of targets positioned to receive the electron beams and generate x-rays in response thereto, each target comprising a predetermined focal spot thereon, and at least one target configured to let electron beams pass therethrough and strike another target at predetermined intervals; and
synchronizing each electron beam to strike, at a predetermined time, a predetermined target comprising a predetermined focal spot thereon wherein at least one target comprises a cut-out section that allows electron beams to pass therethrough and strike another target at predetermined intervals.
14. The method of claim 13 , further comprising:
adjusting an accelerating voltage placed on the electron gun to accomplish at least one of: focusing at least one electron beam, and changing electron beam properties.
15. The method of claim 13 , wherein multi-slice images having a total thickness of up to about 160 mm can be obtained in a single gantry rotation.
16. The method of claim 13 , wherein each target comprises a different focal spot thereon.
17. The method of claim 13 , wherein each electron beam is focused at a different distance.
18. The method of claim 13 , wherein each electron beam is aimed in a different direction.
19. The method of claim 13 , wherein each electron beam strikes a different target having the appropriate focal spot thereon.
20. The method of claim 13 , wherein the plurality of targets rotate about an axis of rotation.
21. The method of claim 13 , wherein a single electron beam, focused at a predetermined distance, strikes only one target, comprising a matching predetermined focal spot thereon, at a time.
22. The method of claim 13 , further comprising:
providing a sensing device for identifying a rotational position of the targets.
23. The method of claim 22 , wherein the sensing device comprises:
a magnetic material disposed on a rotor; and
a magnetic pick-up device disposed in close proximity to the magnetic material, wherein, when the rotor spins around its axis of rotation, the magnetic pick-up device obtains a voltage or current signal as the magnetic material passes thereby, and then the magnetic pick-up device transmits an appropriately treated and amplified signal to the electron gun to do at least one of: change electron beam focusing parameters, and make deflection corrections.
24. The method of claim 13 , further comprising:
adjusting a focal bias voltage placed on the electron gun to accomplish at least one of: focusing at least one electron beam, and changing electron beam properties.
25. A computed tomography or volume computed tomography imaging system, comprising:
an extended multi-spot x-ray source for computed tomography or volume computed tomography imaging, comprising:
an electron gun for producing a plurality of electron beams, each electron beam focused at a predetermined distance and aimed in a predetermined direction; and
a plurality of targets positioned to receive the electron beams and generate x-rays in response thereto, each target comprising a predetermined focal spot thereon, and at least one target configured to let electron beams pass therethrough and strike another target at predetermined intervals;
means for synchronizing each electron beam to strike, at a predetermined time, a predetermined target comprising a predetermined focal spot thereon; and
an x-ray detector, wherein the x-ray source projects a multi-spot beam of x-rays towards the x-ray detector, the x-ray detector detects the x-rays, and an image is created therefrom wherein at least one target comprises a cut-out section that allows electron beams to pass therethrough and strike another target at predetermined intervals.