Abstract: A pot core transformer assembly includes a multiplier comprising a pair of single layer capacitors connected by a pair of high voltage diodes. A pot core transformer is connected in series with the multiplier, and includes a first core half having a first projection, and a second core half having a second projection spaced from the first projection by a first gap. A primary winding is wrapped about the first projection, and a secondary winding wrapped about the second projection. A magnetic shunt is positioned between the first core half and the second core half, and includes a central aperture receiving a portion of the first projection and a portion of the second projection. A second gap is formed between an outer peripheral surface of the magnetic shunt and an interior surface of the first core half and an interior surface of the second core half.

Abstract: A device for producing x-rays includes: a housing that includes a folded high-voltage multiplier coupled to a filament transformer, the transformer coupled to an x-ray tube for producing the x-rays. A method of fabrication and an x-ray source are disclosed.

Abstract: A device for producing x-rays includes: a housing that includes a folded high-voltage multiplier coupled to a filament transformer, the transformer coupled to an x-ray tube for producing the x-rays. A method of fabrication and an x-ray source are disclosed.

Abstract: A miniaturized, increased efficiency x-ray source for materials analysis includes a laser source, an optical delivery structure, a laser-driven thermionic cathode (108), an anode (122), and a target from the laser source and directs the beam onto a surface of the themionic cathode. The surfaces electrons form an electron beam along a beam path. The target element (110) is disposed in the beam path, and emits x-rays in response to incident accelerated electrons from the thermionic cathode. The target element includes an inclined surface that forms an angle of inclination (113) of about 40 degrees with respect to the electon beam path, so that x-rays are emitted from the target substantially at an angle of about 45 degrees with respect to the electron beam path.

Abstract: A miniaturized, increased efficiency x-ray source for materials analysis includes a laser source, an optical delivery structure, a laser-driven thermionic cathode (108), an anode (122), and a target from the laser source and directs the beam onto a surface of the themionic cathode. The surfaces electrons form an electron beam along a beam path. The target element (110) is disposed in the beam path, and emits x-rays in response to incident accelerated electrons from the thermionic cathode. The target element includes an inclined surface that forms an angle of inclination (113) of about 40 degrees with respect to the electon beam path, so that x-rays are emitted from the target substantially at an angle of about 45 degrees with respect to the electron beam path.

Abstract: An apparatus delivers x-rays to at least a portion of an interior surface of a body cavity. The apparatus includes a flexible catheter, at least one balloon or inflatable element affixed to the catheter, one or more flexible probe assemblies, an x-ray generator assembly coupled to the distal end of each probe assembly, and a power supply means. The flexible catheter includes one or more interior channels, and each flexible probe assembly is slidably positionable within a respective interior channel of the catheter. Each balloon, when inflated, defines a predetermined surface contour disposed about an interior region of a body cavity. Each flexible probe includes a transmission path for transmitting activating energy, and may be an optical fiber for transmitting optical energy. The x-ray generator assembly includes an electron source and a target element. The electron source emits electrons in response to activating optical energy transmitted through the transmission path.

Abstract: An x-ray source includes an insulating tube having a cylindrical inside surface defining a cylindrical vacuum cavity, a cathode located near a first end of the insulating tube and adapted to be optically heated for emitting electrons, an anode adapted for a voltage bias with respect to the cathode for accelerating electrons emitted from the cathode, an x-ray emitter target located near a second end of the insulating tube for impact by accelerated electrons, and a secondary emission reduction layer covering at least a portion of the inside surface and adapted to minimize charge build-up on the inside surface, wherein the insulating tube is adapted to be weakly conductive to support a uniform voltage gradient along the insulating tube and across the voltage bias between the cathode and the anode.

Abstract: A therapeutic radiation source includes an in situ radiation detecting system for monitoring in real time an amount of the therapeutic radiation that has been generated. An electron source generates electrons in response to light that is transmitted through a fiber optic cable and impinges upon the electron source. The electrons are accelerated toward the target and strike the target, causing the target to emit therapeutic radiation, such as x-rays. A scintillator is disposed along a path of a portion of the emitted therapeutic radiation, and generates scintillator light corresponding to the intensity of the therapeutic radiation that is incident upon the scintillator. A photodetector in optical communication with the scintillator produces a signal indicative of the intensity of the therapeutic radiation incident upon the scintillator.

Abstract: A method is provided for treating a tumor by pre-irradiation. The location, size, and shape of the tumor is identified. A region that includes the tumor as well as a surrounding portion most likely to contain residual tumorous cells is identified. The identified region is irradiated with therapeutic radiation, such as x-rays, prior to surgical removal of the tumor. The tumor is removed after irradiation of the identified region, leaving only the pre-irradiated surrounding portion. The risk of recurrence of tumorous growth after resection of the tumor may be significantly reduced.

Abstract: A controller is provided for selectively and independently control each of a plurality of therapeutic radiation sources arranged along an array. The controller is operable to selectively generate therapeutic radiation at selected time intervals and at selected intensities. The controller includes intensity control circuitry for controlling the intensity of the therapeutic radiation generated by each therapeutic radiation source. The controller also includes duration control circuitry for controlling the duration of the therapeutic radiation generated by each therapeutic radiation source. The controller may also include a mechanical introducer for inserting the array into a treatment region, and for withdrawing the array from the treatment region.

Abstract: A minaturized tharapeutic radiation source includes a optically driven thermionic cathode having an electron-emissive surface, and a non-planar, x-ray emissive target. A fiber optic cable directs a beam of optical radiation, having a power level sufficient to heat at least a portion of the electron-emissive surface to an electron emitting temperature, from a laser source onto the cathode. An electron beam emitted from said cathode strikes the target, positioned in the electron beam path. The target includes a thin film of x-ray emissive material, adapted to emit therapeutic radiation in response to incident accelerated electrons from the electron beam, and a support structure made of x-ray transmissive material. The target has a non-planar configuration, such as a conical shape or a hemispherical shape, designed to produce a more uniform and intense radiation pattern around the target.

Abstract: A miniaturized, optically driven, therapeutic radiation source is disclosed in which the voltage gradient between a high electron accelerating voltage and the ground potential can be controlled. The electron source and the target element are disposed within a capsule which defines a substantially evacuated region extending along an electron beam axis. The inner surface of the capsule is coated with a weakly conductive or semiconductive coating, so that a substantially uniform voltage gradient is maintained within the evacuated capsule. In this way, the chances of electric flashover or breakdown are reduced. Also, secondary emissions of electrons striking the inner wall of the capsule are reduced. X-ray production efficiency is optimized by maximizing the percentage of electrons propagated directly to the target.

Abstract: A system for delivering therapeutic radiation, such as x-rays, to a treatment region includes a plurality of individually controllable therapeutic radiation sources. The therapeutic radiation sources are selectively and moveably disposed along one or more axes, or upon a two-dimensional surface, or within a three-dimensional volume, so as to form a one-dimensional or a multi-dimensional array. Each therapeutic radiation source includes an electron source for emitting electrons, and an associated target element adapted to emit therapeutic radiation in response to incident electrons. In one embodiment, each therapeutic radiation source is coupled to a distal end of an associated optical delivery structure, which is adapted to direct a beam of optical radiation to impinge upon a surface of the electron source so as to cause emission of electrons therefrom.

Abstract: A miniaturized, optically driven, therapeutic radiation source is disclosed in which the voltage gradient between a high electron accelerating voltage and the ground potential can be controlled. The electron source and the target element are disposed within a capsule which defines a substantially evacuated region extending along an electron beam axis. The inner surface of the capsule is coated with a weakly conductive or semiconductive coating, so that a substantially uniform voltage gradient is maintained within the evacuated capsule. In this way, the chances of electric flashover or breakdown are reduced. Also, secondary emissions of electrons striking the inner wall of the capsule are reduced. X-ray production efficiency is optimized by maximizing the percentage of electrons propagated directly to the target.

Abstract: A therapeutic radiation source includes a spiral-shaped, laser-heated thermionic cathode. A fiber optic cable directs a beam of radiation, having a power level sufficient to heat at least a portion of the electron-emissive surface to an electron emitting temperature, from a laser source onto the cathode. The cathode generates an electron beam along a beam path by thermionic emission, and strikes a target positioned in its beam path. The target includes radiation emissive material that emits therapeutic radiation in response to incident accelerated electrons from the electron beam. The spiral-shaped conductive element has a plurality of spaced apart turns, and is disposed in a vacuum. An interstitial spacing is defined between adjacent turns, so that heat transfer across the spacing between each adjacent turn is essentially eliminated, thereby substantially reducing heat loss in the cathode caused by thermal conduction.

Abstract: A miniaturized, increased efficiency x-ray source for materials analysis includes a laser source, an optical delivery structure, a laser-driven thermionic cathode, an anode, and a target element. The optical delivery structure may be an aspherical lens that focuses a beam of light from the laser source and directs the beam onto a surface of the thermionic cathode. The surface is heated to a temperature sufficient to cause thermionic emission of electrons. The emitted electrons form an electron beam along a beam path. The target element is disposed in the beam path, and emits x-rays in response to incident accelerated electrons from the thermionic cathode. The target element includes an inclined surface that forms an angle of inclination of about 40 degrees with respect to the electron beam path, so that x-rays are emitted from the target substantially at an angle of about 45 degrees with respect to the electron beam path.

Abstract: A therapeutic radiation source includes a spiral-shaped, laser-heated thermionic cathode. A fiber optic cable directs a beam of radiation, having a power level sufficient to heat at least a portion of the electron-emissive surface to an electron emitting temperature, from a laser source onto the cathode. The cathode generates an electron beam along a beam path by thermionic emission, and strikes a target positioned in its beam path. The target includes radiation emissive material that emits therapeutic radiation in response to incident accelerated electrons from the electron beam. The spiral-shaped conductive element has a plurality of spaced apart turns, and is disposed in a vacuum. An interstitial spacing is defined between adjacent turns, so that heat transfer across the spacing between each adjacent turn is essentially eliminated, thereby substantially reducing heat loss in the cathode caused by thermal conduction.

Abstract: A miniaturized, optically driven therapeutic radiation source operates at significantly reduced power levels. The apparatus includes a laser-driven thermionic cathode, a target element, a probe assembly, and a laser source. The probe assembly includes an optical delivery structure, such as a fiber optic cable, that directs a laser beam from the laser source to impinge upon a surface of the thermionic cathode, heating the surface to a temperature sufficient to cause thermionic emission of electrons. The emitted electrons form an electron beam along a beam path. The target element is positioned in the beam path, and includes means for emitting therapeutic radiation, such as x-rays, in response to incident accelerated electrons from the electron beam. Reflector elements may be included to reflect unabsorbed laser radiation back to the thermionic cathode.

Abstract: A therapeutic radiation source includes a optically heated thermionic cathode that is shaped so as to maximize the coupling efficiency of the incident optical radiation to the thermionic cathode. A fiber optic cable directs a beam of radiation, having a power level sufficient to heat at east a portion of the electron-emissive surface to an electron emitting temperature, from a laser source onto the cathode. An electron beam generated by said cathode strikes a target which is positioned in its beam path and which emits therapeutic radiation in response to incident accelerated electrons from the electron beam. The thermionic cathode has a non-planar configuration, such as a conical shape and a concave shape, adapted to allow an incident ray of optical radiation to impinge upon, and undergo absorption from, a plurality of regions within the surface of the cathode in succession.

Abstract: A therapeutic radiation source includes a spiral-shaped, laser-heated thermionic cathode. A fiber optic cable directs a beam of radiation, having a power level sufficient to heat at least a portion of the electron-emissive surface to an electron emitting temperature, from a laser source onto the cathode. The cathode generates an electron beam along a beam path by thermionic emission, and strikes a target positioned in its beam path. The target includes radiation emissive material that emits therapeutic radiation in response to incident accelerated electrons from the electron beam. The spiral-shaped conductive element has a plurality of spaced apart turns, and is disposed in a vacuum. An interstitial spacing is defined between adjacent turns, so that heat transfer across the spacing between each adjacent turn is essentially eliminated, thereby substantially reducing heat loss in the cathode caused by thermal conduction.