Dual energy X-ray source
View Patent ↗A dual energy X-ray source for use in an explosive detection system includes only a single power supply and only a single X-ray tube. The X-ray tube includes only two electron guns and only a single anode. Each electron gun has its own grid and cathode. The X-ray source switches between producing a higher energy X-ray and producing a lower energy X-ray at a frequency of at least 4000 Hz.
1. A dual energy X-ray source comprising:
a power supply; and
only a single X-ray tube, the X-ray tube comprising:
only two electron guns and only a single anode,
each electron gun having a grid and a cathode, a first of the cathodes always connected to receive a first voltage and a second of the cathodes always connected to receive a second voltage, the first voltage being higher than the second voltage.
2. The dual energy X-ray source as claimed in claim 1 wherein each cathode has a heated filament.
3. The dual energy X-ray source as claimed in claim 1 wherein each cathode is a cold cathode that uses field emission.
4. The dual energy X-ray source as claimed in claim 3 wherein each cathode further uses carbon nanotubes.
5. A dual energy X-ray source as claimed in claim 1 wherein the anode is fixed.
6. A dual energy X-ray source as claimed in claim 1 wherein the grid is fixed.
7. A dual energy X-ray source as claimed in claim 1 wherein the X-ray tube is absent a filter.
8. An explosive detection system comprising:
a dual energy X-ray source comprising only a single X-ray tube, the X-ray tube comprising:
only two electron guns and only a single anode,
each electron gun having a grid and a cathode, a first of the cathodes always connected to receive a first voltage and a second of the cathodes always connected to receive a second voltage, the first voltage being higher than the second voltage; and
at least one X-ray detector.
9. The explosive detection system as claimed in claim 8 wherein each cathode has a heated filament.
10. The explosive detection system as claimed in claim 8 wherein each cathode is cold.
11. An explosive detection system as claimed in claim 8 wherein the anode is fixed.
12. An explosive detection system as claimed in claim 8 wherein the grid is fixed.
13. An explosive detection system as claimed in claim 8 wherein the X-ray tube is absent a filter.
14. A multiple energy X-ray source comprising:
a power supply; and
only a single X-ray tube, the X-ray tube comprising:
multiple electron guns and only a single anode,
each electron gun having a arid and a cathode, each of the cathodes always connected to receive a different voltage.
15. A multiple energy X-ray source as claimed in claim 14 wherein the anode is fixed.
16. A multiple energy X-ray source as claimed in claim 14 wherein the grid is fixed.
17. A multiple energy X-ray source as claimed in claim 14 wherein the X-ray tube is absent a filter.