Patent Number: 
Section: claims

1. An X-ray imaging apparatus, comprising:a radiator housing;an X-ray tube being rotatable about a longitudinal axis defined therethrough and being disposed at least partially within the radiator housing, the X-ray tube including a first portion and a second portion;a source of X-ray beams which emits at least one X-ray beam at least partially through the X-ray tube and exiting the X-ray tube at an annular X-ray window peripherally disposed on the X-ray tube adjacent the second portion;at least one filtration material disposed on the X-ray tube and at least partially covering a portion of the annular X-ray window, wherein the X-ray beam becomes filtered as it passes through the filtration material; andwherein rotation of the X-ray tube causes the X-ray beam to pass through a plurality of locations in the annular X-ray window and wherein at least a portion of the X-ray beam is filtered by the filtration material,wherein the X-ray imaging apparatus includes a first filtration material and a second filtration material, a plurality of the first filtration material and a plurality of the second filtration material being disposed in an alternating orientation at least partially covering the annular X-ray window. 2. The X-ray imaging apparatus of claim 1, wherein the at least one filtration material is disposed in a plurality of spaced-apart locations on the X-ray tube. 3. The X-ray imaging apparatus of claim 1, wherein the X-ray tube includes an interior surface and an exterior surface and wherein the at least one filtration material is disposed on an interior surface of the X-ray tube. 4. The X-ray imaging apparatus of claim 1, wherein the X-ray tube includes an interior surface and an exterior surface and wherein the at least one filtration material is disposed on an exterior surface of the X-ray tube. 5. The X-ray imaging apparatus of claim 1, wherein the at least one filtration material is essentially comprised of uranium. 6. The X-ray imaging apparatus of claim 1, wherein the at least one filtration material is essentially comprised of thorium. 7. The X-ray imaging apparatus of claim 1, wherein the first filtration material is made from a material whose K-Shell electron binding energy is outside the range of about 30 keV to about 120 keV and the second filtration material is made from a material whose K-Shell electron binding energy is within the range of about 30 keV to about 120 keV. 8. The X-ray imaging apparatus of claim 1, wherein the first filtration material is aluminum and the thickness is in the range of about 5 mm to about 7 mm. 9. The X-ray imaging apparatus of claim 8, wherein the second filtration material is uranium and the thickness is in the range of about 40 μm to about 60 μm. 10. The X-ray imaging apparatus of claim 1, wherein the X-ray tube includes a voltage setting in the range of about 40 kilovolts and 160 kilovolts. 11. The X-ray imaging apparatus of claim 1, wherein the radiator housing is at least partially filled with a coolant. 12. The X-ray imaging apparatus of claim 1 further defined as an X-ray Computed Tomography (CT) apparatus. 13. A method for rapidly switching the energy spectrum of X-ray beams, comprising:providing an X-ray imaging apparatus, including:a radiator housing;an X-ray tube being rotatable about a longitudinal axis defined therethrough and being disposed at least partially within the radiator housing;a source of X-ray beams which emits at least one X-ray beam at least partially through the X-ray tube and exiting the X-ray tube at an annular X-ray window peripherally disposed on the X-ray tube; andat least one filtration material disposed on the X-ray tube and at least partially covering a portion of the annular X-ray window; androtating the X-ray tube to cause the X-ray beam to pass through a plurality of locations in the annular X-ray window,wherein the X-ray imaging apparatus includes a first filtration material and a second filtration material, a plurality of the first filtration material and a plurality of the second filtration material being disposed in an alternating orientation at least partially covering the annular X-ray window. 14. The method of claim 13, wherein the first filtration material is made from a material whose electron binding energy is outside the range of about 30 keV to about 120 keV and the second filtration material is made from a material whose electron binding energy is within the range of about 30 keV to about 120 keV. 15. The method of claim 13, wherein the at least one filtration material is essentially comprised of an actinide.