Large-area individually addressable multi-beam x-ray system and method of forming same

A method of generating an x-ray image comprising the steps of:

• positioning an object within an imaging zone;
• switching each of a plurality of cathodes on a cathode structure at a predetermined frequency to field emit an electron, each of the plurality of cathodes individually addressable and electrically switched in a programmable sequence to field emit electrons toward an incidence point on a target structure, each cathode comprising a field emissive electron source including a field emissive material having an emitted electron current density of at least 1 mA/cm2 when the cathode is subjected to an applied electrical field of at least 2V/μm;
• emitting an x-ray from a target of the target structure at the predetermined frequency;
• imaging the object;
• and
• detecting the emitted x-ray,
• wherein a position on the target structure from which the x-ray emits corresponds spatially and temporally to a position on the cathode structure from which the electron emits,
• wherein at least one of a circumferential position and an elevation angle of the emitted x-ray is sufficiently discriminated with respect to the object to produce a three dimensional image, and
• wherein the field emissive material is selected from the group consisting of single walled carbon nanotubes, double walled carbon nanotubes, multi-wall carbon nanotubes, nanotubes comprising at least one non-carbon element, and nanorods/nanowires comprising at least one of a metal, a metal oxide, silicon, silicon carbide, silicon oxide, carbon nitride, boron nitride, boron carbide, or a chalcogenide.

A structure to generate x-rays comprising:

• a plurality of individually electrically addressable electron sources defining a plurality of cathodes;
• at least one target placed opposing the cathodes;
• and
• an evacuated chamber that houses the plurality of cathodes and the at least one target,
• wherein the electron sources are field emission electron sources,
• wherein each electron field emission source is a triode-type comprising a field emissive material having an emitted electron current density of at least 1 mA/cm2 when the cathode is subjected to an applied electrical field of at least 2V/μm and a gate electrode positioned parallel to and insulated from a substrate,
• wherein a plurality of electrons are field emitted from the cathode when the electric field between the gate electrode and the field emissive material exceeds a threshold value,
• wherein the plurality of field emitted electrons pass the gate electrode and are further accelerated to impact on the at least one target by an electric field applied between the gate electrode and the at least one target,
• wherein, upon impact, at an incidence point, at least one x-ray having a characteristic wavelength corresponding to a material of the at least one target and at least one x-ray having a continuous wavelength are generated, and
• wherein the field emissive material is selected from the group consisting of single walled carbon nanotubes, double walled carbon nanotubes, multi-wall carbon nanotubes, nanotubes comprising at least one non-carbon element, and nanorods/nanowires comprising at least one of a metal, a metal oxide, silicon, silicon carbide, silicon oxide, carbon nitride, boron nitride, boron carbide, or a chalcogenide.

A structure to generate x-rays comprising:

• a plurality of individually electrically addressable electron sources defining a plurality of cathodes;
• at least one target placed opposing the cathodes;
• and
• an evacuated chamber that houses the plurality of cathodes and the at least one target,
• wherein the electron sources are field emission electron sources comprising a field emissive material having an emitted electron current density of at least 1 m/Acm2 when the cathode is subjected to an applied electrical field of at least 2V/μm, and the field emissive material is selected from the group consisting of single walled carbon nanotubes, double walled carbon nanotubes, multi-wall carbon nanotubes, nanotubes comprising at least one non-carbon element, and nanorods/nanowires comprising at least one of a metal, a metal oxide, silicon, silicon carbide, silicon oxide, carbon nitride, boron nitride, boron carbide, or a chalcogenide.

A device to record x-ray images, comprising:

• an x-ray source comprising a plurality of individually electrically addressable electron sources defining a plurality of cathodes, the plurality of cathodes disposed on a face of a first planar surface, at least one target disposed on a second planar surface, a deflection surface of the second planar surface opposing the face of the first planar surface, and an evacuated chamber that houses the plurality of cathodes and the at least one target;
• an array or matrix of x-ray detectors or x-ray sensitive films opposing the x-ray source, the array or matrix substantially parallel to and at equal distance to the x-ray source;
• and
• an object positioner placed between the x-ray source and the array or matrix,
• wherein the plurality of cathodes includes a field emissive material having an emitted electron current density of at least 1 mA/cm2 when the cathode is subjected to an applied electrical field of at least 2V/μm selected from the group consisting of single walled carbon nanotubes, double walled carbon nanotubes, multi-wall carbon nanotubes, nanotubes comprising at least one non-carbon element, or a nanorod/nanowire comprising at least one of a metal, a metal oxide, silicon, silicon carbide, silicon oxide, carbon nitride, boron nitride, boron carbide, or a chalcogenide.

A method to obtain an x-ray image, the method comprising:

• placing an object in an x-ray source, the x-ray source comprising a plurality of individually electrically addressable electron sources defining a plurality of cathodes, the plurality of cathodes disposed on a face of a first planar surface, at least one target disposed on a second planar surface, a deflection surface of the second planar surface opposing the face of the first planar surface, and an evacuated chamber that houses the plurality of cathodes and the at least one target, an array or matrix of x-ray detectors or x-ray sensitive films opposing the x-ray source, the array or matrix substantially parallel to and at equal distance to the x-ray source, and an object positioner placed between the x-ray source and the array or matrix;
• applying power to at least one of the plurality of cathodes to generate x-ray radiation for a pre-set exposure time;
• exposing the object to the x-ray radiation;
• and
• capturing an x-ray image corresponding to the object by either the x-ray detectors or the x-ray sensitive films,
• wherein the plurality of cathodes includes a field emissive material having an emitted electron current density of at least 1 mA/cm2 when the cathode is subjected to an applied electrical field of at least 2V/μm selected from the group consisting of single walled carbon nanotubes, double walled carbon nanotubes, multi-wall carbon nanotubes, nanotubes comprising at least one non-carbon element, or a nanorod/nanowire comprising at least one of a metal, a metal oxide, silicon, silicon carbide, silicon oxide, carbon nitride, boron nitride, boron carbide, or a chalcogenide.

A device to generate x-ray images comprising:

• an x-ray source comprising a plurality of individually electrically addressable electron sources defining a plurality of cathodes, the plurality of cathodes disposed on a surface of a first ring, at least one target disposed on a second ring, a deflection surface of the second ring opposing the surface of the first ring, and an evacuated chamber that houses the plurality of cathodes and the at least one target;
• an array or matrix of x-ray detectors or x-ray sensitive films on a surface opposing the x-ray source, the array or matrix substantially concentric to and at equal distance to the x-ray source;
• and
• an object positioner placed between the x-ray source and the array or matrix,
• wherein the plurality of cathodes includes a field emissive material having an emitted electron current density of at least 1 mA/cm2 when the cathode is subjected to an applied electrical field of at least 2V/μm selected from the group consisting of single walled carbon nanotubes, double walled carbon nanotubes, multi-wall carbon nanotubes, nanotubes comprising at least one non-carbon element, or a nanorod/nanowire comprising at least one of a metal, a metal oxide, silicon, silicon carbide, silicon oxide, carbon nitride, boron nitride, boron carbide, or a chalcogenide.

A method to obtain an x-ray image, the method comprising:

• placing an object in an x-ray source, the x-ray source comprising a plurality of individually electrically addressable electron sources defining a plurality of cathodes, the plurality of cathodes disposed on a surface of a first ring, at least one target disposed on a second ring, a deflection surface of the second ring opposing the surface of the first ring, and an evacuated chamber that houses the plurality of cathodes and the at least one target, an array or matrix of x-ray detectors or x-ray sensitive films on a surface opposing the x-ray source, the array or matrix substantially concentric to and at equal distance to the x-ray source, and an object positioner placed between the x-ray source and the array or matrix;
• applying power to all of the plurality of cathodes to generate x-ray radiation for a pre-set exposure time;
• exposing the object to the x-ray radiation;
• and
• capturing an x-ray image corresponding to the object by either the x-ray detectors or the x-ray sensitive films,
• wherein the plurality of cathodes includes a field emissive material having an emitted electron current density of at least 1 mA/cm2 when the cathode is subjected to an applied electrical field of at least 2V/μm selected from the group consisting of single walled carbon nanotubes, double walled carbon nanotubes, multi-wall carbon nanotubes, nanotubes comprising at least one non-carbon element, or a nanorod/nanowire comprising at least one of a metal, a metal oxide, silicon, silicon carbide, silicon oxide, carbon nitride, boron nitride, boron carbide, or a chalcogenide.