Abstract:
Disclosed herein are a high-voltage generator for an x-ray source, an x-ray gun, an electron beam apparatus, a rotary vacuum seal, a target assembly for an x-ray source, a rotary x-ray emission target, and an x-ray source. These various aspects may separately and/or together enable the construction of an x-ray source which can operate at energies of up to 500 kV and beyond, which is suitable for use in commercial and research x-ray applications such as computerised tomography. In particular, the high-voltage generator includes a shield electrode electrically connected intermediate of a first voltage multiplier and a second voltage multiplier. The electron beam apparatus includes control photodetectors and photo emitters having a transparent conductive shield arranged therebetween. The rotary vacuum seal includes a pumpable chamber at a position intermediate between high-pressure and low-pressure ends of a bore for a rotating shaft. The rotary target assembly is configured such that when a torque between a bearing housing and a vacuum housing exceeds a predetermined torque, the bearing housing rotates relative to the vacuum housing. The rotary x-ray emission target has a plurality of target plates supported on a hub, the plates being arranged on the hub to provide an annular target region about an axis rotation of the hub. The x-ray gun is provided with a shield electrode maintained at a potential difference relative to the x-ray target different to the electron beam emission cathode.
Abstract:
An X-ray inspection system of the present application is capable of blocking the effect of heat from an X-ray source, thereby making it possible to place a heat-sensitive circuit component in the same housing space as the X-ray source. The X-ray inspection system includes a housing 10 provided with an upper housing space 11, in which an X-ray source 32 housed in a cooling container 30 is placed. Due to pressure of a pump 36, a cooling medium circulates between the cooling container 30 and a heat radiating device 33, thereby suppressing the temperature rise of the cooling container 30. Since the cooling container 30 is placed in the upper housing space 11, the upper housing space 11 serves as a cooling space, suppressing the temperature rise. Therefore, heat-sensitive or heat-producing circuit components can be placed in the upper housing space 11.
Abstract:
A spark gap comprising a cathode and an anode is provided. The spark gap is divided into two partial spark gaps by means of a central piece, namely a high-pressure spark gap and an effective spark gap. The effective spark gap can for example, be used to generate monochromatic x-rays. In order to guarantee a defined switching time, the high pressure spark gap which is initially switched to defined, is used. The switching initiates a potential so high on the centre piece that, when the high pressure spark gap is switched, the effective spark gap can also be switched in a defined manner without significant delays, to a visibly higher voltage.
Abstract:
A radiation generator may include an elongate generator housing having a proximal end and a distal end, a target electrode within the elongate generator housing at the distal end thereof, a charged particle source within the elongate generator housing at the proximal end thereof to direct charged particles at the target electrode. A plurality of accelerator electrodes may be spaced apart within the elongate generator housing between the target electrode and the charged particle source to define a charged particle accelerator section. Each accelerator electrode may include an annular portion having a first opening therein, and a frustoconical portion having a base coupled to the first opening of the annular portion and having a second opening so that charged particles from the charged particle source pass through the first and second openings to reach the target electrode.
Abstract:
A method of operating an acceleration system comprises injecting charged particles into an RF accelerator, providing RF power to the accelerator, and accelerating the injected charged particles. The accelerated charged particles may impact a target to generate radiation. The RF power is based, at least in part, on past performance of the system, to compensate, at least partially, for dose and/or energy instability. A controller may provide a compensated control voltage (“CCV”) to an electric power source based on the past performance, to provide compensated electric power to the RF source. A decreasing CCV, such as an exponentially decreasing CCV, may be provided to the electric power source during beam on time periods. The CCV to be provided may be increased, such as exponentially increased toward a maximum value, during beam off time periods. The controller may be configured by a compensation circuit and/or software. Systems are also described.
Abstract:
Disclosed herein are a high-voltage generator (120) for an x-ray source, an x-ray gun, an electron beam apparatus, a rotary vacuum seal, a target assembly for an x-ray source, a rotary x-ray emission target (500), and an x-ray source. These various aspects may separately and/or together enable the construction of an x-ray source which can operate at energies of up to 500 kV and beyond, which is suitable for use in commercial and research x-ray applications such as computerised tomography. In particular, the high-voltage generator includes a shield electrode (123a, 123b) electrically connected intermediate of a first voltage multiplier (122a, 122b) and a second voltage multiplier (122b, 122c). The electron beam apparatus includes control photodetectors (202a, 202b—not shown) and photo emitters (201a, 202a) having a transparent conductive shield (203a and 203b, 203c—not shown) arranged therebetween. The rotary vacuum seal includes a pumpable chamber (302) at a position intermediate between high-pressure and low-pressure ends of a bore (301) for a rotating shaft (401). The rotary target assembly is configured such that when a torque between a bearing housing (403) and a vacuum housing exceeds a predetermined torque, the bearing housing rotates relative to the vacuum housing. The rotary x-ray emission target (500) has a plurality of target plates (560) supported on a hub, the plates being arranged on the hub to provide an annular target region about an axis rotation of the hub. The x-ray gun is provided with a shield electrode (123a) maintained at a potential difference relative to the x-ray target different to the electron beam emission cathode.
Abstract:
A method of operating an acceleration system comprises injecting charged particles into an RF accelerator, providing RF power to the accelerator, and accelerating the injected charged particles. The accelerated charged particles may impact a target to generate radiation. The RF power is based, at least in part, on past performance of the system, to compensate, at least partially, for dose and/or energy instability. A controller may provide a compensated control voltage (“CCV”) to an electric power source based on the past performance, to provide compensated electric power to the RF source. A decreasing CCV, such as an exponentially decreasing CCV, may be provided to the electric power source during beam on time periods. The CCV to be provided may be increased, such as exponentially increased toward a maximum value, during beam off time periods. The controller may be configured by a compensation circuit and/or software. Systems are also described.
Abstract:
A high voltage device includes a circuit board 12 surrounded by an enclosure 11, potting 13 to provide electrical insulation between the circuit board 12 and the enclosure 11, and a layer of material 14, having a different resistivity than a resistivity of the potting 13, dividing the potting into separate and discrete sections. The layer of material 14 can be multiple layers. Each layer 14 can have a voltage applied, and a voltage of any layer 14 closer to the circuit board 12 can have a higher absolute value than any layer 14 farther from the circuit board 12.
Abstract:
An x-ray source for use in Phase Contrast Imaging is disclosed. In particular, the x-ray source includes a cathode array of individually controlled field-emission electron guns. The field emission guns include very small diameter tips capable of producing a narrow beam of electrons. Beams emitted from the cathode array are accelerated through an acceleration cavity and are directed to a transmission type anode, impinging on the anode to create a small spot size, typically less than five micrometers. The individually controllable electron guns can be selectively activated in patterns, which can be advantageously used in Phase Contrast Imaging.
Abstract:
In an X-ray radiation source, a lid part is fastened to a main part with screws, so that an X-ray tube is secured to a housing while being pressed against an inner surface of the wall part a by a first circuit board. The X-ray tube can be secured stably within the housing by thus being held between the first circuit board and the wall part. The X-ray radiation source uses the first circuit board incorporated in the housing itself for pressing the X-ray tube. This makes it unnecessary to provide new members for pressing the X-ray tube and can prevent the device structure from becoming complicated.