133 results about "Electron linac" patented technology

A radiation therapy / surgery device optimised to meet the needs of the Neurosurgeon is provided, i.e. one for the treatment of tumours in the brain. It combines the qualities of a good penumbra and accuracy, simple prescription and operation, together with high reliability and minimal technical support. The device comprises a rotateable support, on which is provided a mount extending from the support out of the plane of the circle, and a radiation source attached to the mount via a pivot, the pivot having an axis which passes through the axis of rotation of the support, the radiation source being aligned so as to produce a beam which passes through the co-incidence of the rotation axis and the pivot. It will generally be easier to engineer the apparatus if the rotateable support is planar, and more convenient if the rotateable support is disposed in an upright position. The rotation of the rotateable support will be eased if this part of the apparatus is circular. A particularly preferred orientation is one in which the radiation source is spaced from the rotateable support, to allow it to pivot without fouling the latter. It is thus preferred that the mount extends transverse to the support. In this way, the pivot axis is spaced from the rotateable support providing free space in which the radiation source can pivot. Another way of expressing this preference is to state that the pivot axis is located out of the plane of the rotateable support. To simplify the geometry of the device and the associated arithmetic, it is preferred both that the pivot axis is substantially perpendicular to the rotation axis, and that the beam direction is perpendicular to the pivot axis. It is preferred that the radiation source is a linear accelerator. The output of the radiation source is preferably collimated to conform to the shape of the area to be treated.

A radiotherapeutic apparatus using high-energy electron beams to radiate the bed of removed tumor and the residual tumor tissue in excision operation features that the CT or MRI 3D imaging software is used to determine the position of tumor focal, an analog technique is used to determine the incident direction, angle and position of electron beam, a radiotherapeutic plan system is used to calculate the radiation dosage, and a laser locator on the radiating head with straight-line electron accelerator is used to align the electron beam to the tumor focal.

An improved HE LINAC-based ion implantation system is disclosed utilizing direct digital synthesis (DDS) techniques to obtain precise frequency and phase control and automated electrode voltage phase calibration. The DDS controller may be used on a multi-stage linear accelerator based implanter to digitally synchronize the frequency and phase of the electric fields to each electrode within each stage of the accelerator. The DDS controller includes digital phase synthesis (DPS) circuits for modulating the phase of the electric field to the electrodes, and a master oscillator that uses digital frequency synthesis or DFS to digitally synthesize a master frequency and phase applied to each of the DPS circuits. Also disclosed are methods for automatically phase and amplitude calibrating the RF electrode voltages of the stages.

Systems and methods for generating X-rays and neutrons using a single linear accelerator are disclosed. Such system and methods may interrogate an object at times with X-rays and at other times with neutrons, e.g., after suspicious material is detected based on the X-rays. A system may include a single linear accelerator for generating first and second electron beams; first and second targets; a magnet configured to control irradiation of the first and second targets by the first and second electron beams; and a controller that (a) causes the linear accelerator to generate the first electron beam and causes the magnet to direct the beam to first target to generate X-rays; and (b) causes the linear accelerator to generate the second electron beam and causes the magnet to direct the beam to the second target to generate neutrons.

A quality control accessory (QC accessory) is provided which is adapted for use in linear accelerator quality control or in verification of an arbitrary isocentric radiation treatment plan of a patient or radiation sensitive body. The accessory includes an absorber, a detector and an optional orientation device. The absorber is rotationally symmetric, preferably spherical or hemispherical. The detector is adapted to be fixed in a stationary spatial relationship with respect to the absorber. The optional orientation device is adapted to maintain the two dimensional detector (2d detector) and the absorber in a fixed relative spatial relationship with respect to the beam focus of the linear accelerator, when the gantry is rotated, so that the central axis of the beam is essentially orthogonal to the 2d detector and the phantom axis of symmetry is parallel to or aligned with the central axis of the gantry rotation axis.

A system of introducing a particle beam such as a linear accelerator particle beam for low contaminate processing. The system includes an accelerator apparatus configured to generate a first particle beam including at least a first ionic specie in an energy level of 1 MeV to 5 MeV or greater. Additionally, the system includes a beam filter coupled to the linear accelerator apparatus to receive the first particle beam. The beam filter is in a first chamber and configured to generate a second particle beam with substantially the first ionic specie only. The first chamber is associated with a first pressure. The system further includes an end-station including a second chamber coupled to the first chamber for extracting the second particle beam. The second particle beam is irradiated onto a planar surface of a bulk workpiece loaded in the second chamber for implanting the first ionic specie. The second chamber is associated with a second pressure that is higher than the first pressure. Optional beam scanning can also be added between the beam filter and the end-station.

A dual-plunger energy switch assembly for standing wave linear particle beam accelerators capable of operating in a higher energy mode and a lower energy mode employs two mechanical plungers that can be extended different distances inside two side cavities of the linear accelerator. When the linear accelerator is operated in the higher energy mode, both plungers are retracted out of the side cavities. To achieve high output while the linear accelerator is operated in the lower energy mode, the two plungers are radially inserted into the two side cavities to adjust the electromagnetic accelerating field along the length of the accelerator, e.g., one plunger is inserted into a side cavity so that the plunger touches the smile surface of the side cavity, while the second plunger is inserted into a second side cavity so that the plunger is adjacent to, but not touching, the smile surface of the side cavity.

A radiation therapy system including a linear accelerator configured to emit a beam of radiation and a dosimeter configured to detect in real-time the beam of radiation emitted by the linear accelerator. The dosimeter includes at least one linear array of scintillating fibers configured to capture radiation from the beam at a plurality of independent angular orientations, and a detection system coupled to the at least one linear array, the detection system configured to detect the beam of radiation by measuring an output of the scintillating fibers.

The invention relates to a medical apparatus for tumor radiation therapy, in particular to a same-source double-energy medical electron linear accelerator for image guided radiation therapy (IGRT). The same-source double-energy medical electron linear accelerator for the IGRT is characterized in that: an accelerating tube is vertically arranged and is connected with a moving target below the accelerating tube; an energy switch is arranged on the accelerating tube; an X-ray heavy metal target and a low atomic number target are arranged on the moving target; and the X-ray heavy metal target and the low atomic number target are connected with a driving mechanism of the moving target. The same-source double-energy medical electron linear accelerator for the IGRT has the advantages that: energy of an electron beam generated by the accelerating tube is reduced by the energy switch; by using the characteristic that the electron beam impacts the low atomic number target to generate more low-energy beams, X rays with clear portal imaging are obtained; and the same-source double-energy medical electron linear accelerator for the IGRT has the characteristics of easy mode conversion, same source, stable beam, clear image, economy, reliability, simpleness and convenience in clinical use and the like.

The invention discloses a grid-controlled electron gun digital power supply for a medical electron linear accelerator. The grid-controlled electron gun digital power supply comprises an alternating current input module, a power conversion module, a high voltage output module and a comprehensive signal processing system, wherein the alternating current input module is used for filtering and rectifying input alternating current power, performing slow start control on the input alternating current power and providing low voltage auxiliary power for the entire power supply; direct current voltage generated by the alternating current input module is converted into high frequency pulse in the power conversion module; the high voltage output module is used for boosting, rectifying and filtering the high frequency pulse and outputting direct current high voltage Uk; digital loop control is designed in the comprehensive signal processing system; and PWM (Pulse Width Modulation) control is compensated through sampling ray energy and power supplyvoltage fluctuationand real-time dynamic response is made in combination with a PID (Proportion Integration Differentiation) control algorithm, so that the influence of fluctuation in the power grid on an emission beam of the electron gun is eliminated. The sampled data is corrected according to the ambient temperature, so that the interference of ambient temperature variation in high voltage output stability is reduced, and the stability for long-term work of the electron gun is guaranteed.

Disclosed is an adjustable-energy electron accelerator. Its electron accelerating pipe comprises the traveling wave accelerating section [6], the second travelling wave or standing wave accelerating section [5] and the microwave binding-flow hole [7]. The traveling wave accelerating section [6] is ahead, which follow the Standing wave accelerating section [5], the microwave power first feed in the traveling wave accelerating section [6], and is connected with the entry of the standing wave accelerating section [5]. The electron beam firstly enter the micro binding-flow hole via the traveling wave accelerating section, then enter the second traveling wave or standing wave accelerating section [5]. The present invention can decelerate the electron beam in the accelerating structure.

A method and isotope linac system are provided for producing radio-isotopes and for recovering isotopes. The isotope linac is an energy recovery linac (ERL) with an electron beam being transmitted through an isotope-producing target. The electron beam energy is recollected and re-injected into an accelerating structure. The ERL provides improved efficiency with reduced power requirements and provides improved thermal management of an isotope target and an electron-to-x-ray converter.

This is a new technique in IMRT and 3D conformal gamma radiation dose delivery using a linear accelerator with no flattening filter. The technique improves patient radiation therapy by reducing radiation scattered to surrounding normal tissue and reducing electron contamination. It increases dose rate to shorten treatment time. Linear accelerators have for decades come with a photon flattening filter to make the photon profile of planar fluence to make the dose distribution more uniform. These filters, however, resulted in fluence attenuation and contamination of the beam. Now in the age of techniques such as intensity modulated radiation therapy (IMRT) the function of the flattening filter becomes redundant. The flattening filter now merely reduces the efficiency of the beam by reducing the fluence and increasing scattered radiation. Our technique involves removal of the flattening filter for complex treatments. It uses inverse planning along with multi-leaf collimators to shape the dose distribution.

This invention provides one electron line speeder with multiple gear energy adjusting, which comprises electron gun, speeding structure, microwave power source, isolator and magnetic exciting power, wherein, the speeding structure has two parts separately connected to power align machine through isolator and to get micro wave power from microwave power source; the two sections of speeding structure are connected by magnetic iron in certain microwave phase; through changing magnetic iron sensor intensity to change electron beam track length.

A multi-energy cargo inspection system features a compact electron accelerator is used that is more compact, more efficient and less expensive than a single linear accelerator with the same energy. The system has enhanced capabilities to recognize the elemental content of a container which can be used to detect concealed explosive and fissionable materials.

The invention discloses a shaft coupling and side coupling mixed double-beam standing wave electron linear accelerator. Accelerating cavities and shaft coupling cavities are alternately connected to form a body of the double-beam standing wave electron linear accelerator, a metal short-circuit switch is arranged on a side coupling cavity, and the energy state of electron beam current is adjusted by adjusting the insertion length of the short-circuit switch into the side coupling cavity. Therefore, two energy states (high energy and low energy) of electron beam current are achieved through one standing wave electron linear accelerator, a multi-use machine is realized, and the size and cost of imaging and radiation therapy equipment are reduced.

The invention discloses a double-modulator control system of a medical electron linear accelerator. The double-modulator control system comprises a magnetron modulator, a grid-controlled electron gun modulator, a magnetron, a grid-controlled electron gun, an accelerating tube, three microwave detection circuits, a feedback microwave system, a therapeutic head, an automatic dosage control system and a digital signal processing system; the digital signal processing system is connected with the magnetron modulator and the grid-controlled electron gun modulator respectively, the magnetron modulator is connected with the magnetron, a microwave detection circuit is connected between the magnetron and the feedback microwave system, and the other two microwave detection circuits are connected between the inlet and the outlet of the accelerating tube and the feedback microwave system respectively; and the magnetron modulator, the three microwave detection circuits and the automatic dosage control system are connected with the digital signal processing system respectively, and the electron gun modulator is sequentially connected with the grid-controlled electron gun, the accelerating tube and the therapeutic head. The double-modulator control system realizes independent control, and can dynamically adjust the emission capacity of the electron gun in real time.

The invention discloses an energy switch for an on-axis electrical coupling standing wave accelerating tube. The on-axis electrical coupling standing wave accelerating tube comprises multiple accelerating cavities and coupling cavities arranged alternatively, wherein apertures are arranged among the accelerating cavities and the coupling cavities; circular holes are formed in the middle parts of the apertures; the energy switch comprises a platy front end and a pull rod at the back end; a circular hole is formed in the middle of the platy front end; the platy front end is inserted into the coupling cavities, and the pull rod stretches out of the side walls of the coupling cavities; and when the platy front end is inserted in a position where the circular hole in the platy front end coincides with the circular holes in the apertures, a circular waveguide structure is formed by the three circular holes. The energy multi-gear adjustability of a medical electron linear accelerator can be realized through insertion and pull-out of the energy switch.

We propose that during the factory testing of the linac, rather than simply confirming that the beam falls within the permissible ranges set out in the standard, the beam is in fact adjusted towards a standard signature. A new (or existing) linac could then be paired to a new linac, or to an existing linac, such as one that it is to operate alongside or one that it is to replace. Treatment plans would then be transferable between such pairs of linacs. In addition, the standard signature to which the linacs were approximated could be placed towards the centre of the permitted ranges, to produce linacs that were more reliable over the very long term. This requires a linac that has automatically adjustable parameters, so that a suitable programmed computer is able to monitor the output of the linac and adjust its operating parameters. We therefore provide a radiation source comprising a linear accelerator, beam control circuitry for the linear accelerator, an electronic control apparatus for the control circuitry arranged to adjust properties thereof, and a monitor for detecting properties of the radiation beam produced by the linear accelerator, wherein the control apparatus is adapted to retain a set of beam properties and periodically activate the accelerator, measure the current beam properties via the monitor, compare the measured beam properties to the retained beam properties, and potentially adjust the control circuitry properties to align the beam properties towards the retained beam properties. The beam properties that are measured may include at least one of beam flatness and beam width. The retained beam properties can be the properties of the beam produced by the linear accelerator when new, or the properties of a standard beam. The control apparatus is preferably arranged to send a message if the difference between the measured beam properties and the retained beam properties exceeds a threshold. It may also send a message to a remote location if the difference between the measured beam properties and the retained beam properties exceeds a second threshold.

The invention provides an electronic linear accelerator, which comprises an electron beam emitting device used for emitting a kV-level electron beam or an mV-level electron beam, a magnetic deflection system, a therapeutic target and an imaging target. The mV-level electron beam can enter the magnetic deflection system and then shoots out of the magnetic deflection system after being deflected in the magnetic deflection system. The therapeutic target is used for receiving the mV-level electron beam shot out of the magnetic deflection system. The mV-level electron beam bombards the therapeutic target to generate therapeutic rays. The imaging target is positioned between the electron beam emitting device and the magnetic deflection system and is used for receiving the kV-level electron beam. The kV-level electron beam bombards the imaging target to generate imaging rays. According to the technical scheme of the electronic linear accelerator, the design limitation of an existing homologous double-beam linear accelerator due to the existence of a deflection magnet is broken through. The kV-level electron beam will not enter the magnetic deflection system to be deflected, while the kV-level electron beam directly bombards the imaging target to generate imaging rays. The energy of the imaging rays can meet the imaging requirement, so that the utilization efficiency of the kV-level electron beam is improved. Therefore, formed images are high in quality. Meanwhile, the irradiation part can be accurately positioned and the setup error is lowered.

A quality control accessory (QC accessory) is provided which is adapted for use in linear accelerator quality control or in verification of an arbitrary isocentric radiation treatment plan of a patient or radiation sensitive body. The accessory includes an absorber, a detector and an optional orientation device. The absorber is rotationally symmetric, preferably spherical or hemispherical. The detector is adapted to be fixed in a stationary spatial relationship with respect to the absorber. The optional orientation device is adapted to maintain the two dimensional detector (2d detector) and the absorber in a fixed relative spatial relationship with respect to the beam focus of the linear accelerator, when the gantry is rotated, so that the central axis of the beam is essentially orthogonal to the 2d detector and the phantom axis of symmetry is parallel to or aligned with the central axis of the gantry rotation axis.

The invention discloses an independent tuning microwave electron gun with external cathode which is composed of an external negative pole, namely, dipolar gun, a microwave cavity, a tuning mechanism, a first cavity input waveguide, a second cavity input waveguide and a cooling water pipe; the external negative pole and the microwave cavity are connected by Kovar flange argon-arc welding, the tuning mechanism and the microwave cavity are connected by braze welding in a hydrogen furnace, the first cavity input waveguide and the second cavity input waveguide are connected with the microwave cavity by braze welding, but the first cavity input waveguide and the second cavity input waveguide are connected at different longitudinal positions of the microwave cavity with the angles being mutually perpendicular, and then connected with a waveguide transmission line fed with microwave power respectively. The invention is designed to solve manufacture technique, so that the electron gun has simple structure and electron beam is excellent in performance, thus providing a novel electron beam source device for compact type free electron laser and electron linear accelerator.

The invention discloses a self-adaptive traveling wave phase locking type frequency control system for an electronic linear accelerator. The system consists of a control circuit, a servo motor, a microwave discriminator, a reduction gearbox, a position sensor and a computer used for controlling. The system includes E wire with five shifts and X wire with two shifts and includes two working modes of manual / automatic frequency control. The system tracks the resonant frequency of an accelerating tube through adjusting the output frequency of a magnetron, thereby having the advantages of high control precision, fast following speed, wide tracking range, small errors, and the like and guaranteeing the physical properties and index of the whole machine.

The invention discloses an electron gun control circuit for an electronic linear accelerator. The electron gun control circuit comprises an alternating-current power supply circuit, an electron gun adjustable control circuit and a voltage-controlled voltage adjusting and phase modulation module; the electron gun adjustable control circuit outputs a control voltage, and the control voltage is output to the control voltage input end of the voltage-controlled voltage adjusting and phase modulation module; and the output end of the voltage-controlled voltage adjusting and phase modulation module is connected with the alternating-current power supply circuit to control the work of the alternating-current power supply circuit. Stability of electron beam current output by the accelerator can be realized by controlling the filament voltage of an electron gun. By setting a filament voltage preset value, the filament voltage of the electron gun on four potentiometers corresponding to high-energy gears and low-energy gears before and after beams are emitted can be conveniently adjusted. Due to the use of an isolating transformer in the alternating-current power supply circuit, pulse high voltage coming from a modulator and added on the filament of the electron gun can be effectively isolated, and working stability and safety of the electron gun control circuit are also increased. Due to the use of a feedback circuit, the emission of the filament of the electron gun can be automatically adjusted so that the emission of the filament tends to be stable.

Disclosed is an electron linear accelerator having dual purposes and a dual-purpose method of the electron linear accelerator. The electron linear accelerator comprises an accelerating tube, a scanning box, an industrial computed tomography (CT) and a beam deflection system, wherein the beam deflection system comprises a front quadrupole magnet, a deflection magnet, a rear quadrupole magnet and a scanning magnet; the front quadrupole magnet is arranged behind the accelerating tube, the deflection magnet is arranged behind the front quadrupole magnet, and the rear quadrupole magnet and the scanning magnet are arranged behind the deflection magnet; the industrial CT is arranged behind the rear quadrupole magnet and the scanning box is arranged behind the scanning magnet; and the deflection magnet is controlled to be opened or closed, and electronic beam current is selected for moving forwards in a linear mode or for deflecting at an alpha angle, so that the electronic beam current selectively enters the scanning box or the industrial CT. The electron linear accelerator having dual purposes and the dual-purpose method of the electron linear accelerator solve the problem that the requirements of dual purposes on electron beam spot sizes are contradictory. Under the condition that all performances meet the requirements, the cost is reduced. The electron linear accelerator having dual purposes and the dual-purpose method of the electron linear accelerator not only perform electron beam irradiation by using different energy but also generate X rays with different energy, and perform CT imaging.

The scattering screen type electronic beam radiator belongs to the field of radiation processing technology. The electronic beam radiator includes electronic linear accelerator and light limiting tube. Structurally, it features the light limiting tube with flange connected to electronic linear accelerator in the middle of the top cover and water cooled double-layered titanium window assembly corresponding to the drift tube of the accelerator and embedded to the bottom of the flange. There are two layers of support board on the bottom of the flange and thin scattering metal sheets set inside the support boards. The light limiting tube has cooling water space formed by the double-layered walls and may be filled with cooling gas. The water cooled double-layered titanium window assembly is one cooling water space formed by the water cooling box cover and water cooling box bottom. Compared with available technology, the present invention has the advantages of simple structure, self shielding, high efficiency, etc.

The invention provides an anticollision protective device for a medical electronic linear accelerator. The anticollision protective device includes a limit switch which is arranged at a preset horizontal position which is a position to which a lifting floor needs to descend when a rotating rack is located in a preset angle range, wherein the limit switch judges whether the lifting floor triggers the limit switch; a signal conditioning circuit which sends a first digital signal corresponding to the limit switch to a logic judgment circuit; an inclined-angle sensor which is arranged on the rotating rack to detect the angle of the rotating rack; an angle judgment circuit which sends a control signal to the logic judgment circuit when it is judged that the angle is in the preset angle range; the logic judgment circuit which carries out logic calculation on the first digital signal and the control signal; a control circuit which controls the rotating rack to stop rotating when it is judged the calculation result complies with an collision condition; and the rotating rack which is driven to rotate by a driving motor. All components of the device are realized by pure hardware so that the device is simple to control and free from communication circuits and thus the device is high in anti-interference capability and higher in reliability.