摘要:
An electron emitter assembly and a method for adjusting a size of electron beams are provided. The electron emitter assembly includes a laser configured to emit a first light beam. The electron emitter assembly further includes a lens assembly configured to receive the first light beam. The lens assembly is configured to adjust a size of the first light beam between a first predetermined size and a second predetermined size larger than the first predetermined size. The lens assembly emits the first light beam toward a photo-cathode. The photo-cathode is configured to emit a first electron beam having a third predetermined size when the first light beam having the first predetermined size contacts the photo-cathode. The photo-cathode is further configured to emit a second electron beam having a fourth predetermined size when the first light beam having the second predetermined size contacts the photo-cathode. The electron emitter assembly further includes an anode configured to receive the first and second electrons beams from the photo-cathode.
摘要:
An field emitter array system (10) includes a housing (50). An emitter array (80) generates an electron beam and has multiple emitter elements (81) that are disposed within the housing (50). Each of the emitter elements has multiple activation connections (92).
摘要:
An electron emitter assembly and a method for generating an electron beam are provided. The electron emitter assembly includes a laser configured to emit a first light beam and a second light beam. The electron emitter assembly further includes a mirror configured to move to a first operational position to reflect the first light beam toward a first region of a photo-cathode. The mirror is further configured to move to a second operational position to reflect the second light beam toward a second region of the photo-cathode. The photo-cathode is configured to emit a first electron beam when the first light beam contacts the first region and to emit a second electron beam when the second light beam contacts the second region. The electron emitter assembly further includes an anode configured to receive the first and second electron beams from the photo-cathode.
摘要:
An electron emitter assembly and a method for adjusting a power level of an electron beam are provided. The electron emitter assembly includes a laser configured to emit a first light beam. The electron emitter assembly further includes a light-attenuating device configured to receive the first light beam and to attenuate the first light beam between a first light intensity and a second light intensity greater than the first light intensity. The electron emitter assembly further includes a photo-cathode configured to receive the first light beam from the light-attenuating device. The photo-cathode is further configured to emit a first electron beam having a first power level in response to receiving the first light beam having the first light intensity. The photo-cathode is further configured to emit a second electron beam having a second power level greater than the first power level in response to receiving the first light beam having the second light intensity. The electron emitter assembly further includes an anode configured to receive the first and second electrons beams from the photo-cathode.
摘要:
An imaging tube (12) includes a cathode (30) that emits an electron beam (32) and an anode (38). The anode (38) includes multiple target surfaces (36). Each of the target surfaces (36) has a focal spot that receives the electron beam (32). The target surfaces (36) generate multiple x-ray beams (42) in response to the electron beam (32). Each x-ray beam (42) is associated with one of the target surfaces (36). An x-ray imaging system (10) includes the cathode (30) and the anode (38). A controller (28) is electrically coupled to the cathode (30) and adjusts emission of the electron beam (32) on the anode (38).
摘要:
A method for adjusting a focal spot position during a scan of a computed tomography (CT) imaging system having a z-axis. The CT imaging system includes a detector array having a plurality of detector elements and an x-ray tube configured to direct an x-ray beam towards the detector through an object to be imaged. The method includes turning on the x-ray tube and reading a z-ratio from the detector. A shift in a position of a focal spot of the x-ray tube is then determined utilizing the read z-ratio. The method further includes using a transfer function to determine a compensating electronic deflection value; and applying the electronic deflection value to the x-ray tube as at least one of a deflection voltage or a deflection current to track the focal spot in the z-axis direction.
摘要:
A system for generating a tunable X-ray pulse comprises a first electron beam source configured to direct a first electron pulse of predetermined energy and pulse length towards a first interaction zone, a laser beam source configured to direct a first photon pulse of predetermined energy and pulse length towards the first interaction zone to interact with the first electron pulse. The first interaction produces a substantially monochromatic second photon pulse of higher photon energy directed towards a second interaction zone, and a second electron beam source configured to direct a second electron pulse of predetermined energy and pulse length towards the second interaction zone so that the second interaction produces an X-ray pulse of predetermined energy and pulse length in a cascaded inverse Compton scattering (ICS) configuration.
摘要:
A system for generating images by using monochromatic x-rays is described. The system includes an accelerator configured to increase energy of an electron beam, at least one detector element configured to receive x-rays having multiple energies generated by interaction of the electron beam with at least one laser beam, and an image reconstructor configured to reconstruct at least one image by processing the x-rays.
摘要:
A system and method for forming x-rays. One exemplary system includes a target and electron emission subsystem with a plurality of electron sources. Each of the plurality of electron sources is configured to generate a plurality of discrete spots on the target from which x-rays are emitted. Another exemplary system includes a target, an electron emission subsystem with a plurality of electron sources, each of which generates at least one of the plurality of spots on the target, and a transient beam protection subsystem for protecting the electron emission subsystem from transient beam currents and material emissions from the target.
摘要:
A system and method for forming x-rays. One exemplary system includes a target and electron emission subsystem with a plurality of electron sources. Each of the plurality of electron sources is configured to generate a plurality of discrete spots on the target from which x-rays are emitted. Another exemplary system includes a target, an electron emission subsystem with a plurality of electron sources, each of which generates at least one of the plurality of spots on the target, and a transient beam protection subsystem for protecting the electron emission subsystem from transient beam currents, material emissions from the target, and electric field transients.