Large angle anode target for an X-ray tube and orthogonal cathode structure
Technology is described for steep angle of a focal track of an anode of an x-ray tube. In one example, an anode includes a disc-shaped anode and a focal track. The disc-shaped anode includes a bearing-facing surface, a window-facing surface positioned opposite the bearing-facing surface, and a focal track positioned between the window-facing surface and the bearing-facing surface, wherein the focal track is angled with respect to the window-facing surface, and the angle between the focal track and the window-facing surface is between 45° and 89°.
1. An anode for an x-ray tube, comprising:
a disk-shaped cylindrical body including:
a bearing-facing surface,
a window-facing surface positioned opposite the bearing-facing surface, and
a focal track positioned between the window-facing surface and the bearing-facing surface, wherein the focal track is angled with respect to the window-facing surface, and the angle between the focal track and a plane of the window-facing surface is between 45° and 89°.
2. The anode assembly of claim 1 , wherein the window-facing surface is parallel to a diameter of the disk-shaped cylindrical body.
3. The anode assembly of claim 1 , wherein:
the disk-shaped cylindrical body comprises a substrate including carbon fiber composite (CFC), titanium-zirconium-molybdenum (TZM), molybdenum-hafnium-carbon (MEW), other molybdenum alloy, or combination thereof; and
the focal track comprises a coating on the substrate, the coating comprising tungsten (W), rhenium (Re), or combinations thereof.
4. The anode assembly of claim 1 , wherein the angle between the focal track and the window-facing surface is between 65° and 85°.
5. The anode assembly of claim 1 , wherein the angle between the focal track and the window-facing surface is between 74° and 83°.
6. The anode assembly of claim 1 , wherein the anode includes at least two radial slots in the focal track.
7. The anode assembly of claim 6 , wherein at least one of the slots is angled such that one edge of the focal track overlaps another edge of the focal track.
8. The anode assembly of claim 1 , wherein the anode is a rotating anode.
9. An x-ray tube, comprising:
an evacuated enclosure;
an anode disposed within the evacuated enclosure;
a bearing assembly configured to permit the anode to rotate around an anode rotation axis; and
a cathode disposed within the evacuated enclosure, the cathode configured to emit electrons towards the anode to generate x-rays from electrons impinging on the anode, wherein the cathode is oriented transverse to the anode rotation axis.
10. The x-ray tube of claim 9 , wherein:
the cathode is configured to emit electrons substantially radially inward towards the anode rotation axis; and
the anode is configured to generate x-rays in a direction substantially parallel to the anode rotation axis.
11. The x-ray tube of claim 9 , further comprising a window positioned transverse to the anode rotation axis, the window comprising an x-ray transmissive material to allow x-rays to be emitted from the x-ray tube through the window.
12. The x-ray tube of claim 11 , wherein a plane formed by the window is substantially parallel to a window-facing surface of the anode.
13. The x-ray tube of claim 9 , further comprising a focal track positioned between a window-facing surface of the anode and a bearing-facing surface of the anode, wherein the focal track is angled with respect to the window-facing surface, and the angle between the focal track and the window-facing surface is between 45° and 89°.
14. The x-ray tube of claim 9 , further comprising:
a housing at least partially surrounding the evacuated enclosure, and
a high voltage power supply integrated into the housing.
15. The x-ray tube of claim 9 , wherein the anode includes a focal track angled between 1° and 45° with respect to the anode rotation axis.
16. The x-ray system of claim 15 , wherein the focal track is formed by a target coating on the anode.
17. A method of forming an anode for an x-ray tube, the method comprising:
providing a disk-shaped cylindrical anode including:
a bearing-facing surface,
a window-facing surface positioned opposite the bearing-facing surface, and
a taper formed between the window-facing circular plane surface and the bearing-facing surface, wherein the taper is angled with respect to the window-facing surface, and the angle between the taper and a plane of the window-facing surface is between 45° and 89°; and
forming a focal track on the taper, wherein the focal track is configured to generate x-rays when electrons strike the focal track.
18. The method of claim 17 , wherein the focal track is formed by depositing a coating material and includes:
an ion beam enhanced deposition (MED),
a physical vapor deposition (PVD),
a chemical vapor deposition (CVD),
plasma-enhanced chemical vapor deposition (PECVD), or
an atomic layer deposition (ALD).
19. The method of claim 18 , wherein:
a material of the coating includes tungsten (W), rhenium (Re), or combinations thereof; and
a material of the disk-shaped cylindrical anode includes carbon fiber composite (CFC), titanium-zirconium-molybdenum (TZM), molybdenum-hafnium-carbon (MHC), other molybdenum alloy, or combination thereof.
20. The method of claim 17 , wherein the taper, the bearing-facing surface, or the window-facing surface is formed by grinding, polishing, lapping, abrasive blasting, honing, electrical discharge machining (EDM), milling, lithography, industrial etching/chemical milling, or laser texturing the disk-shaped cylindrical substrate.