Abstract: In combination with a diagnostic CT scanner using radiant energy for imaging, an apparatus for therapeutically irradiating a target, comprising a mask that partially attenuates the radiant energy passing therethrough, but transmits through an aperture sufficient radiant energy for imaging. The mask, intermediate the radiant energy source and the target, passes an unattenuated portion of the radiant energy to irradiate the target. The cross-sectional shape and spatial position of the mask aperture can be selectively varied. A post-mask is aligned with the mask aperture and attenuates the radiant energy passing therethrough to an energy level essentially uniform with that of the radiant energy passing through the mask to permit continued imaging during therapeutic irradiation of the target. A method of using the invention in combination with a diagnostic CT scanner using radiant energy for imaging is also provided.

Abstract: A radiation therapy unit with a beam of rays propagating from a focal point along a beam axis comprises a radiator head arranged on the beam axis with a double-focus multi-leaf collimator. The multi-leaf collimator exhibits a plurality of adjacently arranged diaphragm plates which in each case have two side faces, two front faces and an inside and an outside face. Each side face of each diaphragm plate forms a part of a surface area of a cone, all such cones having both a common cone axis which extends perpendicularly to the beam axis through the focal point, and a common cone point which coincides with the focal point. Means are provided for guiding the diaphragm plates so that each diaphragm plate performs a pure rotation about the cone axis during its displacement.

Abstract: An apparatus for slit radiography comprising discrete controllable attenuation elements coacting with a slit diaphragm, each attenuation element being affixed to damping means.

Abstract: This therapy simulator contains a radiation source (1) in a radiator head. An image acquisition unit (7) is connected to the radiator head and can be swivelled jointly with the latter about a patient's couch (9). At least two diaphragm systems, arranged offset in the direction of the principal axis (2) of the radiation source (1), are arranged in the radiator head. At least one of these diaphragm systems is designed as a depth diaphragm system (4) and at least one other is designed as a measuring diaphragm system (5).A therapy simulator is to be created on which, together with the setting of the measuring diaphragm, the corresponding depth diaphragm is adjusted automatically. This is achieved by the actuating elements of the at least two diaphragm systems being designed such that the diaphragm systems projected into the image plane of the image acquisition unit (7) move at the same speed.

Abstract: The diaphragm plates are individually adjustable in two-dimensional fashion. Semi-transparent diaphragm sections at the edges of the diaphragm plates limiting the radiation are adjustable perpendicular to the respective edge with a lever linkage such that the semi-transparent region becomes larger when the diaphragm is closed. A feedback control unit is present for operation. This feedback control unit has two operating pieces as an operating mechanism, which are displaceable by a user to positions similar to the diaphragm plates, and are electrically coupled to the feedback control unit to cause movement of the diaphragm plates to a position corresponding to the position of the operating plates.

Abstract: A dynamic scanning X-ray machine has a detector with an array of crystals which respond to X-rays and a circuit made of semiconductor material, both of which deteriorate when exposed to X-rays. A pair of blinder plates which are opaque to X-rays normally cover the detector and semiconductor material to prevent their deterioration by the X-rays. The blinder plates are separated from each other by an adjustable distance to form a gap which enables the X-rays to reach the detector. An object under study and the blinders move in synchronism through the X-ray field so that a part of the X-ray field forming the shadow of the object passes through the gap formed by the separation between the blinder plates and falls upon the detector, while the detector crystals and semiconductor material are shielded from the remainder of the X-ray field. The shielding of the detector crystals and semiconductor material does not have any effect upon the image of the object under study.

Abstract: A collimating arrangement for use in radiotherapy apparatus has a set of mutually contiguous members (8) for substantially attenuating radiation. The positions of the members (8) are adjustable so that edges (8a) thereof form an adjustable aperture (9) for defining the cross-sectional shape of the beam. A lamp (12) illuminates an area including the beam-defining edges (8a). Each of the members (8) is provided with a respective retroreflector (19) for reflecting illumination from the lamp (12) into the camera (13) substantially independently of the position of the beam-defining edges (8a). A detecting arrangement, including a video camera (13), more responsive to the higher intensity of illumination reflected from the retroreflectors (19) than from respectively adjacent regions in the illuminated area, is used to detect the positions of the retroreflectors (19) which are respectively representative of the positions of the edges of the members.

Abstract: In a radiation therapy machine it is desirable to produce irregular radiation field shapes in order to shield critical organs not invaded by the tumor. A multileaf collimator is formed of a multiplicity of heavy metal bar leaves driven relative to frames which are driven relative to jaws of a rectangular field collimator by electric motors and flexible cables.

Abstract: In a radiation therapy machine it is desirable to produce irregular radiation field shapes in order to shield critical organs not invaded by the tumor. A system is provided using a multileaf collimator formed of a multiplicity of heavy metal bar leaves driven relative to a pair of frames which are driven relative to jaws of a rectangular field collimator. A multiplicity of compensators, one attached to each leaf on one of the pair of frames is used to adjust the local intensity of the radiation within the field. The x-ray beam is limited to a fan with the jaws, the ends and selected parts of the fan are blocked by the multileaf collimator, and the intensity within various portions of the remaining beam is adjusted with compensators. The field of the fan beam is dynamically controlled by these means while the patient table is moved perpendicular to the plane of the fan beam.

Abstract: Radio-diagnostic equipment includes an X-ray tube and a shutter which defines an aperture of modifiable size for allowing X-rays to pass therethrough. The shutter consists of a plurality of individual lamella which lie adjacent each other about the sides of the aperture and can be adjusted individually in a longitudinal direction depending on the size of the object under examination. An X-ray image intensifier and a television camera coupled to it generate a video signal and a monitor reproduces an image of the video signal. An evaluating circuit derives a control signal from the video signal which is applied to a position adjusting device including spring-like elements which can be deflected from an initial position by physical forces for controlling the positioning of each lamella.

Abstract: An X-ray inspection system includes an X-ray source for generating a directed X-ray beam and a linear array detector for measuring the intensity of the received radiation and generating electrical signals representative thereof. A method for aligning the detector with the directed X-ray beam includes removing any part between the X-ray source and the detector, opening an X-ray beam limiter, positioning the linear array detector for maximum signal from each detector element, reducing the X-ray beam limiter opening, detecting whether any signal from a detector element is reduced, moving the limiter for producing a maximum signal on each signal, securing the X-ray beam limiter, and positioning the detector array for maximum signal.

Abstract: A contour collimator has diaphragm plates arranged in displaceable fashion relative to one another. Each diaphragm plate is individually engageable with an adjustment element shared by all of the diaphragm plates for displacing one diaphragm plate relative to the remaining diaphragm plates. An interlock mechanism in engagement with the remaining diaphragm plates retains those plates in their respectively existing positions during displacement of the one plate. The adjustment element is displaceable from the one diaphragm plate to another diaphragm plate which can then be displaced by the adjustment element while the other plates are retained in position.

Abstract: An aperture device defines X-ray beams emitted from X-ray focal points L and R spaced apart from each other along the first direction. This defining operation is performed along the first direction and a second direction crossing the first position, thereby shaping a rectangular X-ray radiation area. Blades defining the two edges of the X-ray beam along the first direction and blades defining two edges of the X-ray beam along the second direction are supported by engaging portions into which screw portions of screw rods are screwed and engaging portions slidably fitted around round portions of the screw rods, respectively. When the screw rods are rotated by activation of corresponding stepping motors, the corresponding engaging portions are moved parallel to the screw rods. The respective blades can be variably moved along the first or second direction, thereby forming an X-ray radiation area having any shape in any position.

Abstract: A variable collimator 10 for shaping the cross-section of the beam 100 is described. The collimator relies upon rods 16 which are positioned around the beam axis a-a with the rod 16 axis b-b perpendicular to the beam axis. The rods are shaped by shaping member 24 which is cut to the shape of an area of a patient or other surface to be irradiated.

Abstract: A primary radiation diaphragm for X-ray examination devices has at least one pair of diaphragm plates movable in opposite directions relative to each other for gating an X-ray beam. The diaphragm plates are displaceably mounted in spaced planes and the respective adjustment limits are selected such that each diaphragm plate can selectively limit the X-ray beam with one of two edges disposed perpendicular to the path of adjustment movement. The edges may have different shapes for adapting the gated field to the shape of the body organ under examination.

Abstract: A collimator apparatus (10 or 100) including one or more bundles of nested rods (11, 11a or 101 or 101a or 201) which define a surface (112, 112a) which interferes with a beam of radiation is described. The apparatus particularly uses coil spring (48) between and along the axis (a--a or c--c) of the rods which are compressed by blocks (13, 14, 13a and 14a or 103, 104, 103a and 104a) to lock the rods in position in holes in the blocks. The apparatus is particularly useful for shaping radiation beams for patient treatment.

Abstract: An apparatus for slit radiography comprising an X-ray source, an X-ray detector positioned behind a body being irradiated, said detector collecting the radiation passed through the body, and a slit diaphragm placed between the X-ray source and the body being irradiated, through which diaphragm there is formed a planar X-ray fan beam, while for obtaining a complete X-ray shadow image of the desired part of the body at least the fan beam performs a scanning movement. There are provided detection means coacting with the X-ray detector and comprising a plurality of sections juxtaposed in the longitudinal direction of the strip-like portion of the X-ray detector irradiated through the slit diaphragm, each section being adapted to produce an electric signal depending upon the radiation impinging instantaneously on the associated section of the X-ray detector.

Abstract: A gamma diffractometer is used for examining or testing samples from the materials flaw aspect. More particularly, single crystal blades of turbo engines are inspected by Roentgen radiation and evaluation of reflections with regard to their half peak width and spacings in the profile or curve representing irradiation intensity (I) as a function of a rotational angle (.alpha.) of a test sample, said spacings representing lattice planes of a plurality of single crystal grains. The half peak widths and the spacings provide an information regarding the presence or absence of material flaws.

Abstract: A primary X-ray diaphragm for X-ray diagnostics devices has at least two pairs of diaphragm plates, each pair being in a common plane and the pairs being in spaced parallel planes, and a common drive connection to both pairs of diaphragm plates for simultaneously moving the plates in each pair in opposite directions perpendicular to a central X-ray beam, the drive connection moving the plates in the plane which is closer to the X-ray focus at a faster rate than the plates in the plane farther from the focus so that the plates in the spaced planes overlap at every plate position. The drive connection may be in the form of pulleys of different diameters connected to a common axle, with tooth belts being entrained around the pulleys and respectively connected to the pairs of plates.

Abstract: The invention relates to a radiodiagnostic apparatus with an x-ray tube, a diaphragm which is semitransparent at least areawise and which clears a slit variable in its width and letting the radiation go through, with an x-ray image intensifier and a television camera coupled thereto for the generation of video signals which is connected to a monitor for reproduction of the video signals. The diaphragm consists of several individual blades which abut against one another in parallel on both sides of the slit and are adjustable in longitudinal direction individually dependent on the size of the object to be viewed. To the television camera an evaluating circuit is connected which supplies a control signal obtained from the video signal to a setting device for the individual blades.

Abstract: A primary-beam collimator for a stereo radiographic x-ray diagnostic installation has an x-ray tube with dual focal points (F1, F2) arranged at a distance from each other. Shutter leaves (1a, 1b, 2a, 2b, 3a, 3b, 4a, 4b) are provided, and adjustable so that two beam pyramids (I from focal point F1, and II from focal point F2) can be individually controlled. Two internal shutter leaves (4a, 4b) are provided for restricting the beam in planes perpendicular to the stereo base F1-F2. These are adjustable between two external shutter leaves--each in the direction of its corresponding external shutter leaf. The internal shutter leaves (4a, 4b) are constructed so that, when adjusted to their external positions, they permit the emission of a central beam-pyramid from a central focal point (FN) and, together with the external shutter leaves (2a, 2b), they close the external shutter openings.

Abstract: A variable width fan beam of radiation is provided in a high speed X-ray transmission system by a plurality of ring collimators with the ring collimators being mounted whereby spacing between ring collimators can be varied. In preferred embodiment an arcuate array of radiation detectors are mounted in an annular housing which functions as one of the ring collimators.

Abstract: The invention relates to diaphragm means arranged close to the film in an X-ray spot film device. The diaphragm means comprises a first diaphragm with several rectangular aperture sections. The sections are displaced in the horizontal direction and have different vertical dimensions. A second diaphragm assembly has vertically extending diaphragm edges. By moving the first diaphragm to different positions in the radiation path, the aperture can be adapted to exposure formats of different vertical dimensions.

Abstract: The invention provides a block for partially limiting a radiation beam, allowing a first part of this beam to be limited corresponding to a first maximum half angle of opening.This rectilinearly movable block comprises a cylindrical active surface.Because of this active surface, said block defines new limits for the beam without modifying the starting orientation of this active surface in dependence on the positions which it may occupy through its rectilinear movement.

Abstract: A collimator for an X-ray examination apparatus has a plurality of diaphragm plates adjustable relative to each other in pairs for defining a cone of radiation having a variable rectangular cross-section, and has a plurality of additional diaphragm plates mounted for pivotal movement into the four corner regions of the radiation cone for defining an approximately circular radiation cone of variable diameter. Each additional diaphragm plate has a substantially triangular plan shape and are movable by respective parallelogram linkages with one edge facing the radiation cone, the edge facing the radiation cone being alignable perpendicularly to the angle bisector of the respective corner in which the additional diaphragm plate is located. The additional diaphragms are respectively pivotable substantially radially in the direction of the axis of symmetry of the collimator.

Abstract: The definition diaphragm for the X-ray beam located at the image receiver serves to eliminate part of the stray radiation. According to the invention, the diaphragm comprises a frame and a plurality of partial overlap members each having one portion made from lead rubber, so that it can be turned down perpendicular to the plane of the opening, so that the radial dimensions of the diaphragm are reduced to a minimum. Application is to conventional radiology.

Abstract: Filter for use in medical x-ray apparatus to permit higher intensity x-ray exposure in the heart and mediastinum area while maintaining a normal level of x-ray exposure in other areas of the body, particularly in the lung area. The filter comprises a sheet of radiation absorbing material having an opening therein, said opening corresponding to the spine and central portion of the heart. Accordingly, the upper portion of the filter exhibits a relatively narrow opening which becomes gradually wider toward the lower portion of the filter.

Abstract: An apparatus is disclosed providing a variable aperture energy beam collimator. A plurality of beam opaque blocks are in sliding interface edge contact to form a variable aperture. The blocks may be offset at the apex angle to provide a non-equilateral aperture. A plurality of collimator block assemblies may be employed for providing a channel defining a collimated beam. Adjacent assemblies are inverted front-to-back with respect to one another for preventing noncollimated energy from emerging from the apparatus. An adjustment mechanism comprises a cable attached to at least one block and a hand wheel mechanism for operating the cable. The blocks are supported by guide rods engaging slide brackets on the blocks. The guide rods are pivotally connected at each end to intermediate actuators supported on rotatable shafts to change the shape of the aperture. A divergent collimated beam may be obtained by adjusting the apertures of adjacent stages to be unequal.

Abstract: The exemplary disclosure includes a patient support, an x-ray tube with a diaphragm installation comprising diaphragm plates for the limitation of the x-ray beam irradiating the patient, and a cassette changer for x-ray film cassettes. The cassette changer is a large cassette changer for the entire area to be detected. The diaphragm installation exhibits a fixed diaphragm which limits the maximum size of the x-ray beam, and mechanism for the individual, independent adjustment of movable diaphragm plates determining the dimension of the x-ray beam in the longitudinal direction of the patient support.

Abstract: An X-ray collimator is disclosed having longitudinal and cross shutter assemblies disposed between an input port and an output port. Image area boundaries are defined by two pairs of inner edge portions. Mating inner edge portions of each pair move in an essentially rectilinear path.

Abstract: A masking apparatus and palpitator cone drive system for an X-ray spotfilming device. The masking apparatus comprises first and second pairs of shutter-like members mounted for reciprocating movement in two mutually orthogonal directions. Each mask member of the second pair includes first and second relatively moveable elements that operate in a telescope-like manner. A drive system including a reversible motor and a feedback potentiometer actuates the elements at first and second speeds so that the elements reach their retracted and extended positions simultaneously. The cone drive system includes a drive motor, a drive belt and drive assembly for driving the cone between retracted and operative positions. A cone lock is engageable with a keeper located at a cone-advanced position of the drive assembly and is released by the drive belt whenever the drive motor is energized in the cone-retracting direction.

Abstract: A radiation absorption shield assembly is disclosed for controlling the configuration of the radiation sensitive field of a radiation detecting camera. The shield assembly includes a first annular lead shield element defining a first aperture and mounted to the camera for blocking out a fixed field of radiation. The assembly also includes a second annular lead shield element in series with the first which defines a second aperture movable with respect to the first aperture. Attached to and in a spaced parallel relation with the first shield element is a circular radiation transparent disk which defines a thin gap to accommodate the second shield element. The second shield element is slidably adjustable within the gap, transverse to the first element, by one conducting a radiation study, to vary the configuration of a region of interest defining a field area through which radiation can pass from the patient for detection by the camera.

Abstract: The invention relates to a computer tomography apparatus for determining the absorption distribution in a relevant zone of a body, this zone being irradiated by unattenuated radiation, while the part of the body which is situated outside this zone is irradiated at the most by attenuated radiation. The radiation outside the relevant zone is attenuated in accordance with the invention by means of absorber pieces which are moved to and fro during an examination in a direction parallel to the rotary shaft around which the X-ray source is rotated. As a result, the intensity of the radiation is modulated in the time outside the zone, so that on average it is attenuated, without giving rise to hardening effects.

Abstract: A collimator assembly for defining an aperture for the passage of a diagnostic x-ray beam in an x-ray diagnostic apparatus which may, for example, be used in computer assisted tomography. The collimator assembly comprises a framework adapted to be secured to the x-ray apparatus contiguous the x-ray tube, and includes a first and a second blade subassembly lying in a common plane with each other in the path of x-rays emanating from the x-ray tube. Leaf spring means connect each of the blade subassemblies to the framework, the leaf spring means biasing the first and second blade subassemblies into abutting relation to each other whereby to define a zero aperture condition for the passage of a diagnostic x-ray beam through said collimator assembly to the patient.