Patent Number: 
Section: claims

1. A multi-step X-ray contrast sensitivity gauge, comprising:a first step comprising:a first planar top face; anda first planar bottom face, the first planar top face being parallel to the first planar bottom face, the first step having a first thickness between the first planar top face and the first planar bottom face, the first planar top face comprising a first plurality of recesses of differing depths; and a second step comprising:a second planar top face; anda second planar bottom face, the second planar top face being parallel to the second planar bottom face, the second step having a second thickness between the second planar top face and the second planar bottom face that is greater than the first thickness, the second planar top face comprising a second plurality of recesses of differing depths; the first planar bottom face of the first step being coplanar with the second planar bottom face of the second step. 2. The sensitivity gauge of claim 1, the first planar top face comprising a first recess, a second recess, and a third recess, the first recess having a first depth that is 1% of the first thickness, the second recess having a second depth that is 2% of the first thickness, and the third recess having a third depth that is 4% of the first thickness, the second planar top face comprising a fourth recess, a fifth recess, and a sixth recess, the fourth recess having a fourth depth that is 1% of the second thickness, the fifth recess having a fifth depth that is 2% of the second thickness, and the sixth recess having a sixth depth that is 4% of the second thickness. 3. The sensitivity gauge of claim 1 being a unitary structure. 4. The sensitivity gauge of claim 1, the first step and the second step being modular steps. 5. The sensitivity gauge of claim 4, the first step comprising a first threaded aperture and the second step comprising a second threaded aperture, the first and second apertures configured to receive a first threaded fastener and a second threaded fastener, respectively, the sensitivity gauge of claim 4 further comprising:a bracket that is operative to couple the first step and the second step, the bracket comprises a first bracket aperture and a second bracket aperture that receive the first threaded fastener and the second threaded fastener, respectively. 6. The sensitivity gauge of claim 1, wherein a difference between the first thickness and the second thickness is approximately one inch. 7. The sensitivity gauge of claim 1, the first planar top face having a first length and a first width, the first plurality of recesses each extending the first width of the first planar top face. 8. The sensitivity gauge of claim 7, wherein the recesses in the first plurality of recesses have identical widths of approximately 0.5 inches. 9. The sensitivity gauge of claim 7, the second planar top face having a second length and a second width, the second plurality of recesses each extending the second width of the second planar top face, the recesses in the first plurality of recesses being in alignment with the recesses in the second plurality of recesses. 10. The sensitivity gauge of claim 1 being composed of one of stainless steel, iron, aluminum, brass, Lucite, or Poly (methyl methacrylate). 11. The sensitivity gauge of claim 1, wherein the second thickness is at least six inches. 12. The sensitivity gauge of claim 1, further comprising a plurality of other steps each having respective planar top surfaces that comprise recesses of varying depths. 13. A system, comprising:an X-ray contrast sensitivity gauge that comprises a plurality of steps of varying thicknesses, each step in the plurality of steps comprising a top face and a plurality of recesses, wherein depths of the plurality of recesses are a function of a thickness of the step associated therewith;an X-ray source that is positioned to project X-rays onto top faces of the steps in the X-ray contrast sensitivity gauge; anda detector that detects an amount of attenuation of the X-rays caused at least partially by the X-ray contrast sensitivity gauge. 14. The system of claim 13, wherein a thickness of a step in the plurality of steps is at least five inches. 15. The system of claim 13, wherein depths of the recesses on a step in the X-ray contrast sensitivity gauge are approximately 1% of a thickness of the step, approximately 2% of the thickness of the step, and approximately 4% of the thickness of the step. 16. The system of claim 13, further comprising a computing device that generates an image based at least in part upon the amount of attenuation detected by the detector, the image indicative of a contrast-to-noise ratio of the detector for a step thickness and recess depth. 17. The system of claim 13, the steps of the X-ray contrast sensitivity gauge being modular. 18. The system of claim 13, the X-ray source emitting X-rays at an energy above 5 MeV. 19. The system of claim 13, the X-ray source emitting X-rays at an energy above 20 MeV. 20. An X-ray contrast sensitivity gauge, comprising:a plurality of modular steps of differing thicknesses, each modular step in the plurality of modular steps comprising a plurality of recesses with differing depths that are a function of a thickness of the step associated therewith; andcoupling means that couples the plurality of modular steps.