Abstract: The present disclosure provides a driving mechanism configured to drive a target object to perform a linear motion, wherein the target object includes at least one of a plurality of leaves of a multi-leaf collimator. The driving mechanism may include an output component including an output member. The driving mechanism may also include a transmission component configured to operably connect the output component and the target object. The transmission component may include an output end and an input end. The input end may be operably connected with the output member. The output end may be operably connected with the target object. A linear velocity of the output end may be larger than a linear velocity of the input end.

Abstract: The present application provides an initial, or first, packed arc setup to be compared with predefined arc setup constraints. These predefined arc setup constraints constrain at least one or more of the number of patient table angles per target volume, the number of times the gantry moves along one arc per table angle, the sum of gantry span per metastasis over all arcs, and the minimum table span. Based on the result of the comparison between the first packed arc setup with the predefined arc setup constraints, a second arc setup is automatically suggested. The automatically suggested second arc setup may then be compared with the first arc setup by calculating a score for both setups. Several iterations of such a method can be carried out based on the comparison between an arc setup and the following, subsequent arc setup in the iteration.

Abstract: A multi-leaf collimator includes a driving component, a controller and n leaf-group layers, where n is an integer greater than or equal to 2, wherein each leaf-group layer includes one group of leaves or two opposing groups of leaves, each group of leaves includes a plurality of leaves, each of the leaves includes a front end surface and a rear end surface which are opposite to each other, and each of the leaves is movable so that the front end surfaces of the leaves in the multiple leaf-group layers form a variable-shaped region that allows beams to pass through; and the rear end surface of the leaf is connected to the driving component, and the controller is configured to control the driving component to drive the leaf to move.

Abstract: Disclosed a leaf positioning device (100) for a multi-leaf collimator, comprising: a plurality of positioning signal transmitters which are in the leaf guide rail box, wherein the plurality of positioning signal transmitters are arranged opposite to a first end surface of leaves of the multi-leaf collimator; a plurality of positioning signal receivers which are in the leaf guide rail box and corresponding to the plurality of positioning signal transmitters, wherein the plurality of positioning signal receivers are arranged opposite to a second end surface of the leaves of the multi-leaf collimator; wherein, the plurality of positioning signal transmitters are configured to transmit positioning signals to the plurality of positioning signal receivers, and the plurality of positioning signal receivers are configured to generate output signals according to the positioning signals; a positioning device which is connected to each of the plurality of positioning signal receivers, wherein the positioning device is c

Abstract: A computer implemented method of determining a resultant treatment plan for a proton radiation therapy system based on given dose volume constraints, wherein the resultant treatment plan is optimized for treatment time comprises accessing the dose volume constraints and range information, wherein the range information indicates acceptable deviations from the dose volume constraints. Based on the proton radiation therapy system, the method further comprises accessing machine configuration information comprising a plurality of machine parameters that define a maximum resolution achievable in irradiating a patient. Further, the method comprises iteratively adjusting the plurality of machine parameters to values which decrease the maximum resolution and simulating a plurality of candidate treatment plans to generate a plurality of treatment plan results, wherein each treatment plan result comprises: a respective treatment time and a respective plan quality.

Abstract: During the generation of a panoramic x-ray recording, the use of semi-transparent x-ray screens allows the patient's x-ray exposure to be reduced when partial x-ray images are created, in spite of relatively large overlapping areas between the partial x-ray images.

Abstract: In radiation therapy, treatment objectives applicable to different identified structures in a patient's body (e.g., a target structure and an organ at risk (OAR)) may conflict due to overlap between the structures. Automated systems and methods can detect and resolve such conflicts. For example, a set of modified regions that do not overlap with each other can be defined, and a modified treatment objective for each modified region can be determined based on the original treatment objectives. The modified regions and modified treatment objectives can be used in treatment planning processes.

Abstract: A method of determining the shape of a radiation beam of a radiotherapy system at a treatment position, the system comprising a radiation source and a multi-leaf collimator disposed between the radiation source and the treatment position. The multi-leaf collimator includes an array of moveable leaves positioned to intersect and block parts of the radiation beam to define the shape of the radiation beam at the treatment position. The leaves of a group are aligned such that the planes of the leaves in that group converge at a point displaced laterally from the radiation source. The method includes, for each leaf in the array positioned to intersect the radiation beam, determining a projected width with respect to the radiation beam, the projected width being greater than the thickness of the respective leaf, and using the projected leaf width to determine the shape of the radiation beam at the treatment position.

Abstract: A computer implemented method of determining a resultant treatment plan for a proton radiation therapy system based on given dose volume constraints, wherein the resultant treatment plan is optimized for treatment time comprises accessing the dose volume constraints and range information, wherein the range information indicates acceptable deviations from the dose volume constraints. Based on the proton radiation therapy system, the method further comprises accessing machine configuration information comprising a plurality of machine parameters that define a maximum resolution achievable in irradiating a patient. Further, the method comprises iteratively adjusting the plurality of machine parameters to values which decrease the maximum resolution and simulating a plurality of candidate treatment plans to generate a plurality of treatment plan results, wherein each treatment plan result comprises: a respective treatment time and a respective plan quality.

Abstract: Radiotherapy apparatus comprises a source of radiation mounted on a chassis, the chassis being rotatable about a rotation axis and the source being adapted to emit a beam of radiation along a beam axis that intersects with the rotation axis; a patient support, moveable along a translation axis; a set of magnetic coils located on either side of the beam, for establishing a magnetic field at the point of intersection, spaced from that point along a first direction; the translation axis, the rotation axis, and the first direction being substantially parallel; and further comprising a multi-leaf collimator fixed in its orientation with respect to the source of radiation, the multi-leaf collimator comprising a plurality of elongate leaves disposed with their longitudinal directions substantially aligned with the first direction and movable in that direction between a withdrawn position in which the leaf lies outside the beam.

Abstract: An interventional system includes an introduction element (4) such as a catheter for being introduced into an object (9), for instance, a person. A moving unit (2) such as a robot moves the introduction element within the object. A tracking image generating unit (3) generates, using a radiation beam (7), tracking images of the introduction element within the object. A controller (8) controls the tracking image generating unit depending on movement parameters of the moving unit, which are indicative of the movement. The control operation of the controller (8) allows reducing radiation dose applied to the object.

Abstract: The invention relates to a tomography system (TA) comprising a first (QD1) and a second (QD2) beam source-detector pair for capturing one series (A1, A2) of projection image data sets (PB1, PB2) each from one projection angle (W1, W2) each and a volume image production system (VE) for producing a series (AV) of volume images (VB) of a vascular system (GS) while taking into account first confidence values (VW1) of the first pixel values (PW1) and/or while taking into account second confidence values (VW2) of the second pixel values (PW2). The confidence value (VW1, VW2) of a pixel value (PW1, PW2) depends on a pixel-specific traversing length (L) that a projection beam (PS1, PS2) traverses on a path through parts (Gi) of the vascular system (GS) from the first (Q1) or the second (Q2) beam source to a pixel-specific sensor element (S) of the associated first (D1) or second (D2) detector.

Abstract: The present specification discloses a high speed scanning system for scanning cargo carried by rail. The system uses of a two-dimensional X-ray sensor array with, in one embodiment, a cone-beam X-ray geometry. The pulse rate of X-ray source is modulated based on the speed of the moving cargo to allow a distance traveled by the cargo between X-ray pulses to be equal to the width of the detector, for a single energy source, and to half the width of the detector for a dual energy source. This ensures precise timing between the X-ray exposure and the speed of the passing object, and thus accurate scanning of cargo even at high speeds.

Abstract: This multileaf collimator is provided with multiple leaves which limit the area irradiated by a radiation beam and which are arranged in the thickness direction. Each of the leaves is provided with a protruded portion which is formed protruding towards a first surface of the leaf, a depressed portion which is formed in the second surface of the leaf and into which the protruded portion formed on another leaf is inserted, a first curved surface which is formed between the first surface of the leaf and the lateral surface of the protruded portion, and a second curved surface which is formed between the second surface of the leaf and the lateral surface of the depressed portion.

Abstract: An embodiment of the present invention provides a radiation therapy device including: a main body; a gantry coupled to a side of the main part and rotatable relative to the main part in at least one direction; a radiation head provided on a side of the gantry to emit radiation; an image acquisition unit facing the radiation head to detect radiation emitted from the radiation head and obtain images by converting the detected radiation into electric signals; and a reference image acquisition frame provided on a side of the radiation head and including a plurality of markers formed thereon.

Abstract: These teachings provide for administering a radiation treatment plan to a patient in a single radiation treatment session using a multi-leaf collimator that is comprised of pairs of selectively movable collimating leaves. By one approach this comprises administering a sequential plurality of modulated radiation doses to the patient, where the sequential plurality of modulated radiation doses comprises at least a substantial majority of a planned total radiation dose for the radiation treatment session and where each modulated radiation dose is administered while modulating a radiation beam with the multi-leaf collimator using a curtain pattern (or, perhaps more typically, a plurality of curtain patterns).

Abstract: A method for dealing with the effects of inertia in a radiotherapy apparatus is disclosed. The method may include catering for inertia in advance by incorporating inertia factors into an output from a delivery control system which adapts the treatment plan by incorporating the inertia factors, or by including the inertia factors as a constraint in the treatment planning process. The instructions delivered to the geometry items may reflect their inertia behavior and can therefore be followed very closely. This may indicate that a departure from that plan will be correspondingly more likely to indicate an error by the geometry item. When a geometry item needs to accelerate or decelerate, less error may arise and thus the error-checking regime may not necessarily make allowances for such departures from the intended path, thereby tightening the error tolerances. Error-checking may be safely carried out locally for each component.

Abstract: An X-ray diagnostic apparatus of an embodiment includes an image generator, a detection unit, and an irradiation control unit. The image generator successively generates X-ray images based on X-rays emitted from an X-ray tube and transmitted through a subject. The detection unit detects a position of a predetermined target included in the successively generated X-ray images. The irradiation control unit identifies, based on the detected position of the predetermined target, a region in which the predetermined target can be visualized in the X-ray images, and performs control to reduce an X-ray irradiation dose to a region other than the identified region.

Abstract: A method for delivering therapeutic radiation to a target includes positioning a multi-aperture collimator on the skin within a trajectory of orthovoltage x-rays directed at the target, thus generating an array of minibeams, each of width between 0.1 mm to 0.6 mm. The skin is irradiated with the array. An effective beam of therapeutic radiation, which may be a solid beam, is delivered to the target at a predetermined tissue depth by merging adjacent orthovoltage x-ray minibeams sufficiently to form the effective beam. The effective beam may be formed proximal to the target. The depth at which the effective, preferably, solid, beam is formed is controlled by varying one or more of the spacing of the minibeams in the array, the minibeam width, the distance from the x-ray source to the collimator, and the x-ray source spot size. Planar minibeams can be arc-scanned while continuously modulating beam shape and intensity.

Abstract: A method for generating an at least three-dimensional display data set of a time parameter relating to the chronological spreading of a contrast medium introduced into a vessel system is provided. A series of chronologically successive x-ray images of digital subtraction angiography from at least two different projection directions showing the chronological spreading of the contrast medium is used. The method includes determining a three-dimensional position for at least one correspondence point and/or correspondence region defined, in each case, in at least one x-ray image of a projection direction. For each three-dimensional position, a time parameter assigned to the three-dimensional position is determined by evaluation of time-intensity curves assigned to the correspondence points or correspondence regions over the series. The display data set formed from the three-dimensional positions is displayed with the assigned time parameters.

Abstract: A multi level multileaf collimator employs leaves with leaf tips having a non-square shape in a beam's eye view to improve beam shaping effect and penumbra performance. The multi level multileaf collimator includes a first multileaf collimator in a first level comprising beam blocking leaves longitudinally movable in a first direction, and a second multileaf collimator in a second level comprising beam blocking leaves longitudinally movable in a second direction. The first direction may be generally parallel with the second direction and the leaves of the first multileaf collimator may laterally offset the leaves of the second multileaf collimator. The beam blocking leaves of the first multileaf collimator may comprise an end portion having a non-square shape in a beam's eye view.

Abstract: The invention relates to a contour collimator for radiotherapy, comprising a plurality of plate-shaped diaphragm elements provided in a guiding block and movably arranged with respect to one another to form a contour diaphragm for a radiation beam emitted by a radiation source towards the collimator, and at least one drive for moving the diaphragm elements, wherein a drive of its own is associated with each diaphragm element, the drives of a group of diaphragm elements are arranged substantially adjacent to one another, and the drive is a linear motor, wherein each linear motor comprises a linearly movable rod directly fixed to the associated diaphragm element. The invention facilitates a design of a contour collimator with a shape being as compact as possible, and wherein both precise and stable adjustability of the diaphragm elements is achieved without a backlash. In this way improvements to contour collimators are provided.

Abstract: The present invention relates to a balanced support device, comprising: a wagon configured to move along a wagon rail, a frame connected to the wagon and extending over a vertical distance from the wagon, a rail connected to the frame and a carriage movably arranged on said rail, at least one protruding arm comprising a support member for supporting amass, wherein the protruding arm is pivotably connected to the carriage, wherein the protruding arm comprises multiple segments which are movable relative to one another in order to allow the support member to move toward and away from the frame, wherein the support member is mounted to the protruding arm via a rotary connection, allowing the support member including a mass to be rotated, and a vertical balance system for exerting an upwards force on the carriage for counteracting a weight of the mass, the arm and the carriage, wherein the vertical balance system is constructed and arranged to control said force in order to balance masses of different weights.

Abstract: A collimating system (100) for collimating radiation received under different angles for performing tomography is described. The collimating system (100) comprises a static collimator (110) comprising a plurality of collimating apertures (112), shutters (120) for separately and temporarily shutting at least two of said collimating apertures (112), wherein the shutters (120) having a shutting element (122) for blocking said at least two collimating apertures (112), and at least one collimating element (140) distinct from the shutting element (122) for collimating radiation passing through non-shut collimating apertures (112) in a direction so as to control overlap between radiation stemming from different non-shut collimating apertures (112). The invention also relates to an imaging system comprising such a collimating system, a method for collimating and a corresponding controller and software related products.

Abstract: A radiation generating apparatus includes a radiation generation tube including an electron emitting source having an electron emitting member, a transmission type target, a tubular backward shielding member having an electron passing hole facing the target layer at one end, located at the electron emitting source side of the transmission type target, and connected to the periphery of the base member. The radiation generating apparatus further includes a collimator having an opening for defining an angle for extracting the radiation at the opposite side of the electron emitting source side of the transmission type target, and an adjusting device connected to the collimator, and configured to vary an opening diameter of the opening, wherein the target layer has a portion separated from a connection portion of the base member and the backward shielding member at the periphery.

Abstract: Provided is a device for multi-portal irradiation of particle beams which makes it possible to carry out multi-portal irradiation by remote operation without an operator having to enter an irradiation room. This device for remotely multi-portal irradiation of particle beams includes an irradiation room and a control room. The irradiation room comprises an irradiation device for emitting a particle beam at an irradiation target, an irradiation control device for controlling the position and direction of the irradiation device, and a support stand for supporting the irradiation target. The control room, in turn, includes a control device and a remote operation controller. The control device controls the position and direction of the irradiation device by controlling the irradiation control device.

Abstract: 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.

Abstract: Certain disclosed embodiments concern a method and an apparatus for determining molecular structure. One embodiment comprises producing sample ions from a sample, cooling molecules of the sample ions by either embedding sample ions in superfluid droplets, such as superfluidic helium droplets, or subjecting sample ions in a cooled ion trap, to a selected temperature approaching absolute zero. Plural cooled sample ions confined in a diffraction zone are oriented using a laser, and a diffraction image is produced from oriented sample ions using an electron beam. Molecular structure is determined using collected images from different orientations obtained under different polarization directions of the orientation laser. Embodiments of an apparatus for determining molecular structure also are disclosed. The apparatus operation, data accumulation and processing are controlled by software.

Abstract: An X-ray collimator has a collimation plate, and a shielding box made of a tungsten plastic composite, the shielding box having an opening on the top and the bottom thereof respectively, and a support part for supporting the shielding box. The collimation plate is disposed on the shielding box or the support part. Compared to the use of the shielding box alone, the collimator reduces the volume of the collimator without reducing its shielding performance.

Abstract: A multi-leaf collimator for a radiotherapy apparatus comprises at least one array of laterally-spaced elongate leaves, each leaf being driven by an associated motor connected to the leaf via a drive means so as to extend or retract the leaf in its longitudinal direction, the drive means comprising a sub-frame on which at least a subset of the motors are mounted, the sub-frame being mounted at a location spaced from the leaf array in a direction transverse to the lateral and longitudinal directions, and including a plurality of threaded drives disposed longitudinally, each being driven by a motor and being operatively connected to a leaf thereby to drive that leaf.

Abstract: There are provided a leaf row in which a plurality of leaf plates are arranged in the thickness direction of the row in such a way that the respective one end faces of the leaf plates are trued up and a leaf plate drive mechanism that drives each of the plurality of leaf plates in such a way that the one end face approaches or departs from a beam axis. In each of the leaf plates, a facing side facing a leaf plate that is adjacent to that leaf plate in the thickness direction is formed of a plane including a first axis on the beam axis; the leaf plate drive mechanism drives the leaf plate along a circumferential orbit around the second axis, on the beam axis, that is perpendicular to the beam axis and the first axis.

Abstract: A real-time fluoroscopic imaging system includes a collimator and a detector which are rotationally movable independent of the support assembly, e.g., c-arm, to which they are mounted. Rotational movement of the collimator and the detector are coordinated such that the orientation of the detector with respect to the collimator does not change. The collimator may include a geared flange member to facilitate rotation, and may be a single molded piece formed of a plastic such as tungsten polymer material. The system may also include a plurality of interchangeable collimators characterized by different shapes. A display is provided to present an image to an operator, and image orientation logic displays a target anatomy in a selected orientation regardless of orientation of the target anatomy relative to the detector, and regardless of rotation of the detector.

Abstract: A multilevel MLC includes a first set and a second set of a plurality of pairs of beam blocking leaves arranged adjacent one another. Leaves of each pair in the first set are disposed in an opposed relationship and longitudinally movable relative to each other in a first direction. Leaves of each pair in the second set are disposed in an opposed relationship and longitudinally movable relative to each other in a second direction generally parallel to the first direction. The first and second sets of pairs of leaves are disposed in different planes.

Abstract: A leaf module for a multi-leaf collimator comprises a leaf unit and a leaf drive unit. The leaf unit comprises a leaf for shielding beams from a selected area. The leaf unit is mounted displaceably in an adjusting direction with relation to the leaf drive unit. The leaf drive unit is designed to displace the leaf unit linearly in the adjusting direction. The leaf drive unit comprises at least one drive mechanism which operates based on piezoelectric actuation, being designed such that the leaf drive unit thoroughly encloses the leaf unit within a plane being oriented substantially perpendicularly related to the adjusting direction. The multi-leaf collimator can comprise a plurality of leaf modules while being shaped as compact as possible. Both precise and stable adjustability of the leaf unit is achieved with the leaf module.

Abstract: A multi-leaf collimator for a radiotherapy apparatus comprises at least one array of laterally-spaced elongate leaves, each leaf being driven by an associated motor connected to the leaf via a drive means so as to extend or retract the leaf in its longitudinal direction, the drive means comprising a sub-frame on which at least a subset of the motors are mounted, the sub-frame being mounted at a location spaced from the leaf array in a direction transverse to the lateral and longitudinal directions, and including a plurality of threaded drives disposed longitudinally, each being driven by a motor and being operatively connected to a leaf thereby to drive that leaf.

Abstract: The present system and method for simulating particles and waves is useful for calculations involving nuclear and full spectrum radiation transport, quantum particle transport, plasma transport and charged particle transport. The invention provides a mechanism for creating accurate invariants for embedding in general three-dimensional problems and describes means by which a series of simple single collision interaction finite elements can be extended to formulate a complex multi-collision finite element.

Abstract: A multi-leaf collimator for a radiotherapy apparatus comprises at least one array of laterally-spaced elongate leaves, each leaf being driven by an associated motor connected to the leaf via a drive means so as to extend or retract the leaf in its longitudinal direction, the drive means comprising a sub-frame on which at least a subset of the motors are mounted, the sub-frame being mounted at a location spaced from the leaf array in a direction transverse to the lateral and longitudinal directions, and including a plurality of threaded drives disposed longitudinally, each being driven by a motor and being operatively connected to a leaf thereby to drive that leaf.

Abstract: A multi-leaf collimator device for radiotherapy, including: a frame that has a box shape and has through-holes formed in top and bottom surfaces thereof; a plurality of collimators that are received in the frame, wherein each of the collimators includes a rack gear formed on the top surface of the collimator, the collimators are symmetrically arranged in a left-right direction about a central portion of the frame, and are slidably provided on the frame; and a motion driving unit that includes a pinion gear that is formed to be detachable from the rack gear formed on the top surface of the collimator, and is provided on the frame to move the pinion gear in a front-back direction of the frame and an up-down direction of the frame.

Abstract: An apparatus includes an x-ray source operable to generate x-ray beams, a collimator comprising one or more leaves configured to modify the x-ray beams, a motorized system operable to move the one or more leaves of the collimator independently in or out of the x-ray beams, and a controller configured to synchronize operation of the x-ray source and the motorized system, allowing modification of the x-ray beams substantially in real time with generation of the x-ray beams. At least one leaf or each of the leaves of the collimator may be configured to modulate a beam quality of the x-ray beams.

Abstract: A method of delivering radiation in a session includes delivering radiation towards a patient using a radiation system, wherein the radiation is delivered based at least in part on a physiological phase or a position of the patient, after the radiation is delivered, changing a configuration of the radiation system, wherein the act of changing the configuration is performed independent of at least one motion of the patient, and delivering additional radiation towards the patient after the configuration of the radiation system is changed, wherein the acts of delivering radiation and the act of changing the configuration are performed in response to a processor executing a treatment plan that prescribes a plurality of packages and a transition, the transition prescribing the act of changing the configuration of the radiation system when no radiation is being delivered by the radiation system.

Abstract: These various embodiments are employed in conjunction with the use of both a multi-leaf collimator and jaws that are interposed between a source of radiation and a treatment target while sourcing radiation from the source of radiation towards the treatment target. Generally speaking, during some portion of the aforementioned treatment, these teachings provide for manipulating the jaws to more tightly constrain, in at least one dimension, a beam-shaping aperture as is formed by the multi-leaf collimator.

Abstract: A CT collimator comprising: a first gate and a second gate arranged in parallel on a slide rail, the first gate being fixed to a support rack of the CT collimator via elastic members; an electromagnet system arranged on one of the first gate and the second gate; and a metal plate arranged on the other side of the one of the first gate and the second gate relative to the electromagnet system, one end of the metal plate being fixed on the other of the first gate and the second gate and the other end of the metal plate extending to below the electromagnet system, wherein the electromagnet system is configured to engage the first gate and the second gate via the metal plate when the electromagnet system is triggered.

Abstract: A multi-leaf collimator includes leaf drives and two sets of displaceable leaves arranged side by side and facing each other to impress a high-energy beam with the shape of an irregularly formed treatment object. Each of the leaves assumes a position oriented along the shape of the treatment object by means of a leaf drive and each are equipped with a gear rod-like drive engagement in the direction of the displacement. A leaf-side pivotable gear segment is located, together with a motor-side gear segment, on a segment disk that engages with the gear rod-like drive engagement. A pinion drivable by a motor engages with the motor-side gear segment. The segment discs are arranged side by side for each set of leaves as a package on one axis. The motor-side gear segments of two segment disks located next to each other are staggered so that they will not abut each other.

Abstract: A multilevel MLC includes a first set and a second set of a plurality of pairs of beam blocking leaves arranged adjacent one another. Leaves of each pair in the first set are disposed in an opposed relationship and longitudinally movable relative to each other in a first direction. Leaves of each pair in the second set are disposed in an opposed relationship and longitudinally movable relative to each other in a second direction generally parallel to the first direction. The first and second sets of pairs of leaves are disposed in different planes.

Abstract: A radiotherapeutic apparatus comprises a source of therapeutic radiation, a source of visible light arranged to cast a light field corresponding to the beam of radiation, and a multileaf collimator for shaping the beams, wherein a filter is disposed in the path of the visible light beam having a plurality of linear dark sections corresponding to leaves of the collimator. This prevents the incident light from falling on the leaves and removes the ghost images at source. By placing the filter in the head, the line can be very narrow and will be blurred into penumbra at the isocentre. This is therefore a very inexpensive yet effective method of reducing ghosting. A mirror can deflect the path of the visible light to correspond to that of the radiation beam, and the filter can be disposed anywhere in the beam path, such as prior to the mirror, subsequent to the mirror and prior to the collimator, or subsequent to the collimator.

Abstract: A multi-leaf collimator for radiation therapy in which the position of the leaves are determined by measuring a magnetic field allows to determine the leaf position with enhanced precision, and is at the same time robust to perturbations or disturbances. The magnetic sensor may comprise a magnetic encoder that varies in a predefined pattern along a lengthwise direction of the magnetic element, in particular according to a step function.

Abstract: A system and method for producing an intensity modulated arc therapy (“IMAT”) treatment plan are provided. A plurality of segmentations are generated, from which the IMAT treatment plan is determined. Apertures within each segmentation are ordered by minimizing the total leaf movement between pairs of segmentations in adjacent angles, during which corresponding minimum total leaf movement values between such pairs are calculated. From these segmentations, a network model is used to select those segmentations to be used in the IMAT treatment plan. The apertures in the selected segmentations are then modified by minimizing total leaf movement relative to the selected segmentations, and subject to physical constraints such as a maximum leaf movement constraint or interdigitation constraint. Segmentation errors in the modified segmentations are then locally minimized using a network model and a row-non-convexity measure to determine the order in which apertures are to be optimized.

Abstract: An X-ray collimator for controlling an X-ray radiation field, having a lower base member, a pair of regulating members, a pair of surrounding members having substantially U-shaped forms in planar view, N columnar members surrounded by the pair of surrounding members (where N is 4, 6, or 8), a guiding member, a pair of moving members moving parallel to the opposed surfaces of the regulating members, an upper base member, a first motor for horizontally moving the pair of moving members, and a second motor for moving the columnar members. The first motor is driven to horizontally move the pair of moving members over the same distance in opposite directions. The second motor is configured to move one of the columnar members along an internal surface of the surrounding member surrounding the columnar member, thereby moving the other N?1 columnar members sequentially.

Abstract: A proton beam collimator comprising (a) titanium or (b) stainless steel containing no tungsten or (c) containing no tungsten or brass. The collimator comprises a multi-leaf collimator (MLC). The apparatus further comprises an integrated circuit (IC) mounted adjacent the collimator, the IC subject to exposure to atomic particles, illustratively, neutrons.

Abstract: Apparatus for location-detection of an object within a region comprising a reflective element mountable on the object, a scanning light source adapted to issue a beam of light in a scanning pattern illuminating a point that moves over the region, a detector for light reflected from the reflective element and a control unit adapted to report the position of an object based on the point in the scanning pattern at which the detector detects light returned from the reflective element relative to at least one point in the scanning pattern at which the detector detects light returned from a reflective object.