X-ray system for irradiating material used in transfusions

• US 7,706,506 B1
• Filed: 12/12/2008
• Issued: 04/27/2010
• Est. Priority Date: 12/14/2007
• Status: Expired due to Fees

• Current Assignee: Applied X-Rad Technology, LLC
• Original Assignee: Applied X-Rad Technology, LLC
• Inventors: Woodruff, Ralph R., Toshkov, Stoyan A., Donchev, Todor I.
• Primary Examiner(s): THOMAS, COURTNEY D
• Application Number:
  US12/316,503
• Time in Patent Office: 501 Days
• Field of Search: 378 64- 69, 378/119, 378/121, 378/140, 378156-159
• US Class Current: 378/121
• CPC Class Codes: G21K 1/10 Scattering devices; Absorbing devices; Ionising radiation filters
• CPC Class Codes: G21K 5/08 Holders for targets or for other objects to be irradiated
• CPC Class Codes: G21K 5/10 with provision for relative movement of beam source and object to be irradiated
• CPC Class Codes: H01J 2235/062 Cold cathodes
• CPC Class Codes: H01J 2235/083 Bonding or fixing with the support or substrate
• CPC Class Codes: H01J 2235/1204 of the anode
• CPC Class Codes: H01J 2235/1295 Contact between conducting bodies
• CPC Class Codes: H01J 2235/163 shaped for a particular application
• CPC Class Codes: H01J 2235/18 Windows, e.g. for X-ray transmission
• CPC Class Codes: H01J 35/065 Field emission, photo emission or secondary emission cathodes
• CPC Class Codes: H01J 35/116 Transmissive anodes acting as a window H01J35/186
• CPC Class Codes: H01J 35/13 Active cooling, e.g. fluid flow, heat pipes
• CPC Class Codes: H01J 35/186 used as targets or X-ray converters

Abstract

A system for irradiating material used in transfusions. The material can be pre-transfused blood, blood components and marrow. The system includes a vacuum chamber with a plate cathode inside. The cathode has a large beam electrode field-electron emissive surface with a selected cross-sectional shaped area. A power supply is connected to the cathode for generating negative high-voltage pulses and causing a selected cross-sectional shaped beam of electrons to be emitted. An electron window is also disposed inside the vacuum chamber and made of thin metal foil. The electron window receives the selected cross-sectional shaped beam of electrons therethrough and onto an electron target disposed outside the vacuum chamber. The electron target receives the selected cross-sectional shaped beam of electrons thereon and generates a selected cross-sectional shaped X-ray beam. A cathode filter is disposed next to the electron target and eliminates low energy beams from the spectrum of the X-ray beam. The filtered X-ray beam exposes the material to high energy beams for irradiation.

Claims

1. A system for irradiating material used in transfusions, the material can be pre-transfused blood, blood components and marrow, the system comprising:

a vacuum chamber;

a cathode disposed inside the vacuum chamber, the cathode having a large beam electrode emissive surface, the emission surface having a selected cross-sectional shaped area;

a power supply connected to the cathode for generating negative high-voltage pulses thereto, whereby the negative high-voltage pulses causing a selected cross-sectional shaped beam of electrons to be emitted from the selected cross-sectional shaped area of the emissive surface of the cathode;

an electron window disposed inside the vacuum chamber, the electron window made of thin metal foil, the thin metal foil having a low atomic number, the electron window for receiving the selected cross-sectional shaped beam of electrons therethrough;

an electron target disposed outside the vacuum chamber, the electron target positioned substantially parallel to the electron window and in a spaced relationship thereto, the electron target receiving the selected cross-sectional shaped beam of electrons thereon and generating a selected cross-sectional shaped X-ray beam; and

an X-ray beam filter in contact with and disposed next to the electron target and parallel thereto, the filter spaced apart from the material to be irradiated by the X-ray beam, the filter eliminating low energy beams from the spectrum of the X-ray beam when the X-ray beam is received therethrough, the filtered X-ray beam exposing the material to high energy beams from the spectrum of the X-ray beam.

2. The system as described in claim 1 further including a radiation sensor disposed next to the material to be irradiated, the radiation sensor connected to a radiation controller, the radiation controlled connected to the power supply, the radiation sensor measuring a total absorbed radiation dose by the material from the X-ray beam.

3. The system as described in claim 1 wherein the emissive surface of the cathode has an annular cross-sectional area for generating an annular cross-sectional shaped beam of electrons.

4. The system as described in claim 1 wherein the emissive surface of the cathode has an angular cross-sectional shaped area for generating an angular cross-sectional shaped beam of electrons.

5. The system as described in claim 1 wherein the width of the beam of electrons and the width of the X-ray beam is at least as wide as the width of the material to be irradiated.

6. The system as described in claim 1 wherein the width of the beam of electrons is equal to the width of the X-ray beam.

7. The system as described in claim 1 wherein the power supply is a Marx generator, or Tesla transformer generator, the generator generating negative pulses with respect to the window, between −

1000 kV and −

200 kV at a frequency between 0.1 Hz and 400 Hz.

8. The system as described in claim 1 wherein the metal foil electron window is made of titanium, titanium alloy, vanadium, chromium, cobalt, stainless steel or nickel, the metal foil electron target is made of molybdenum, tantalum, tungsten, rhenium, osmium, iridium, platinum or gold and the cathode filter is made of aluminum, copper, or zinc.

15. The system as described in claim 1 wherein the generator is a Marx generator, the generator generating negative pulses between −

1000 kV and −

200 kV at a frequency between 0.1 Hz and 400 Hz.

9. A system for irradiating material used in transfusions, the material can be pre-transfused blood, blood components and marrow, the system comprising:

a vacuum chamber;

a cathode disposed inside the vacuum chamber, the cathode having a large beam electrode emissive surface, the emission surface having a selected cross-sectional shaped area;

a high-voltage generator connected to the cathode for generating negative high-voltage pulses thereto and having pulse widths between 50 nanoseconds and 1 millisecond, whereby the negative high-voltage pulses causing a selected cross-sectional shaped beam of electrons to be emitted from the selected cross-sectional shaped area of the emissive surface of the cathode;

an electron window disposed inside the vacuum chamber, the electron window made of thin metal foil, the thin metal foil having a low atomic number, the electron window for receiving the selected cross-sectional shaped beam of electrons therethrough;

an electron target disposed outside the vacuum chamber, the electron target positioned substantially parallel to the electron window and spaced apart in a range of 5 to 30 mm, the electron target receiving the selected cross-sectional shaped beam of electrons thereon and generating a selected cross-sectional shaped X-ray beam; and

an X-ray beam filter disposed next to the electron target and parallel thereto, the filter spaced apart from the material to be irradiated by the X-ray beam, the filter eliminating low energy beams from the spectrum of the X-ray beam when the X-ray beam is received therethrough, the filtered X-ray beam exposing the material to high energy beams from the spectrum of the X-ray beam.

10. The system as described in claim 9 further including a radiation sensor disposed next to the material to be irradiated, the radiation sensor connected to a radiation controller, the radiation controlled connected to the power supply, the radiation sensor measuring a total absorbed radiation dose by the material from the X-ray beam.

11. The system as described in claim 9 wherein the emissive surface of the cathode has an annular cross-sectional shaped area for generating an annular cross-sectional shaped beam of electrons.

12. The system as described in claim 9 wherein the emissive surface of the cathode has an angular cross-sectional area for generating an angular cross-sectional shaped X-ray beam.

13. The system as described in claim 9 wherein the width of the beam of electrons and the width of the X-ray beam is at least as wide as the width of the material to be irradiated.

14. The system as described in claim 9 wherein the width of the beam of electrons is equal to the width of the X-ray beam.

16. A system for irradiating material used in transfusions, the material can be pre-transfused blood, blood components and marrow, the system comprising:

a vacuum chamber;

a plate cathode disposed inside the vacuum chamber, the cathode having a large beam electrode emissive surface, the emission surface having a selected cross-sectional shaped area;

a power supply connected to the cathode for generating negative high-voltage pulses thereto, whereby the negative high-voltage pulses causing a selected cross-sectional shaped beam of electrons to be emitted from the selected cross-sectional shaped area of the emissive surface of the cathode;

an electron target disposed inside the vacuum chamber, the electron target receiving the selected cross-sectional shaped beam of electrons thereon and generating a selected cross-sectional shaped X-ray beam;

an X-ray beam filter bonded to and disposed next to the electron target, the filter eliminating low energy beams from the spectrum of the X-ray beam when the X-ray beam is received therethrough, the filtered X-ray beam exposing the material to high energy beams from the spectrum of the X-ray beam;

an electron window disposed inside the vacuum chamber and spaced apart from the filter and parallel thereto, the electron window made of thin metal foil, the thin metal foil having a low atomic number, the electron window for receiving the filtered X-ray beam therethrough and exposing the material to be irradiated by the X-ray beam.

17. The system as described in claim 16 further including a radiation sensor disposed next to the material to be irradiated, the radiation sensor connected to a radiation controller, the radiation controlled connected to the power supply, the radiation sensor measuring a total absorbed radiation dose by the material from the X-ray beam.

18. The system as described in claim 16 wherein the emissive surface has an annular cross-sectional area for generating an annular cross-sectional shaped beam of electrons.

19. The system as described in claim 16 wherein the emissive surface of the cathode has an angular cross-sectional area for generating an angular cross-sectional shaped beam of electrons.

20. The system as described in claim 16 wherein the width of the beam of electrons and the width of the X-ray beam is at least as wide as the width of the material to be irradiated and the width of the beam of electrons is equal to the width of the X-ray beam.