Abstract: An apparatus for spatial modulation of an x-ray beam has a number of planar attenuation elements for x-ray radiation that are disposed in a grid on a carrier and can be pivoted or tilted by a piezoelectric actuator, independently of one another, between at least two positions. One or more sensors with which a piezoelectrically-caused length and/or width and/or position change of the piezoelectrically influenced regions can be detected, are arranged on piezoelectrically influenced regions of the attenuation elements or the actuators. A significant dose reduction and/or dynamic adjustment thereof can be achieved with the apparatus by image adaptation in many areas of x-ray imaging, since a precise determination of the position of each attenuation element in real time is enabled.

Abstract: A collimator includes a pair of first plate members which define an X-ray passing aperture by a spacing between their opposed end faces, a second plate member which is movable in a direction parallel to a moving direction of the first plate members, a pair of third plate members which are movable symmetrically with each other in a direction perpendicular to the moving direction of the first plate member and which define an X-ray passing aperture by a spacing between their opposed end faces, and a fourth plate member which is movable in a direction parallel to the moving direction of the third plate members.

Abstract: The present invention is a method for treatment planning and delivery of the radiation treatment plan for the intensity-modulated radiation therapy (IMRT) treatment using linear accelerators (LINACs) not equipped with a multileaf collimator (MLC). The present invention makes the use of a simpler collimator consisting of only 4 collimator jaws. In addition, the method for treatment planning of the present invention may be performed on a computer separate from the LINAC control computer, so that the treatment planning system can generate IMRT treatment plans for LINACs and collimator jaws from different vendors.

Abstract: Depth diaphragm for an x-ray device, which diaphragm has a plurality of adjustable diaphragm blades (1) for displaying an area being examined, which blades (1) can be moved in such a way that said area being examined can be displayed asymmetrically.

Abstract: The invention relates to a collimator (1) for defining a beam of energetic rays (2) which is emitted from an essentially punctiform radiation source (3) and is oriented onto an object (1) to be treated. The collimator is especially used for the stereotactic conformation radiotherapy of tumors. The collimator (1) is embodied in such a way that an irregular object (4) can be scanned by rays (2, 2?) which are defined by an opening in the collimator. The invention also relates to a program for controlling the collimator. In order to define the contours (29, 29?, 29?) of the objects (4) to be irradiated in a simple but highly accurate manner, especially with a precise definition of the irradiation fields, the collimator comprises a plurality of different sized openings (5, 5? 5?). One of the openings (5, 5?, 5?) can be selectively displaced in a polydirectional manner on a strip (6) having a spherical surface, and the central axis (7) thereof is oriented towards the radiation source (3).

Abstract: A snapshot backscatter radiography (SBR) system and related method includes at least one penetrating radiation source, and at least one substantially transmissive radiation detector. The substantially transmissive radiation detector is interposed between an object region to be interrogated and the radiation source. The substantially transmissive radiation detector receives and detects forward radiation from the radiation source before transmitting a portion thereof to interrogate the object region, wherein a portion of backscattered radiation provided by the object region is detected by the detector. A changeable collimating grid having a plurality of spaced apart radiation absorbing features is coupled to structure changing a position of the plurality of features and is disposed in at least one of the path of the forward radiation and the path of the backscattered radiation.

Abstract: An X-ray diagnostic device has an X-ray tube and a diaphragm housing in which diaphragm plates for limiting an X-ray field are contained, as are a lamp and a mirror. The lamp and mirror are configured so that, when the lamp is on, the light therefrom is reflected by the mirror so that the reflected ray field coincides with the hypothetical X-ray field. At least one filter for filtering the X-rays is disposed in the diaphragm housing. The mirror and the filter or filters are attached to a single disk that rotates around an axis such that either the mirror or a filter is within the hypothetical X-ray field.

Abstract: A radiation therapy device and a method of changing the spatial dose distribution surrounding a focus are disclosed. At least a subset of the radioactive sources in a source carrier is linearly displaceable relatively to at least a subset of collimator passage inlets, or vice versa.

Abstract: A technique for selectively attenuating a radiation exposure in which a configurable collimator is employed between the radiation source and the radiation target. The configurable collimator typically comprises an array of independently addressable elements each of which has at least a high and a low attenuation state, though intermediate states may also be accommodated. The elements of the array may be selectively addressed to determine their state and to determine the attenuation profile of the collimator. One embodiment of the technique employs an array of microactuated attenuating louvers which may be selectively actuated to determine their radiation transmittance. A second embodiment of the technique employs a suspension of attenuating nematic colloids which may be ordered by the application of an electric or magnetic field. The ordered state of the nematic colloids within an element determine the radiation transmittance of that element.

Abstract: A method and device which dynamically detects, tracks and filters interfering signals with sufficient speed (i.e. within one IS-95 CDMA data. frame period, or 20 ms) and fidelity to eliminate or greatly reduce the deleterious effects of narrow band interferer signals on a CDMA link. When inserted in an RF signal path an Adaptive Notch Filter (ANF) detects narrow band interferors above a threshold level within the CDMA signal. Detection is accomplished by continuous scanning of a preset excision band, e.g. a specified narrow band associated with an AMPS system. Detected interferors are then automatically acquired and suppressed. This is achieved by electronically placing a rejection notch at the frequency of the interferors. Multiple notch filters may be used to simultaneously suppress multiple interferors. In the absence of interferors a bypass mode is selected allowing the RF signal to bypass the notch.

Abstract: One aspect of the present invention is a method for imaging an organ of a patient that includes steps of: scanning a volume of a patient's body including an organ of the patient with a computed tomographic (CT) imaging system having a radiation source and detector coupled to a rotating gantry, the detector array having a z-direction parallel to an axis of rotation of the gantry and an x-direction transverse to the z-direction; acquiring attenuation data from a plurality of staggered half detector segments of the detector array; and reconstructing an image including the patient's organ using the acquired attenuation data.

Abstract: An X-ray inspection system is provided having an X-ray source and first and second collimators. The first and second collimators are arranged in relation to the source and the target such that the portion of the target actually illuminated by The X-ray beam is substantially equal to the size of a selected inspection zone.

Abstract: A method and apparatus for detecting radiation including x-ray, gamma ray, and particle radiation for radiographic imaging, and nuclear medicine and x-ray mammography in particular, and material composition analysis are described. A detection system employs fixed or configurable arrays of one or more detector modules comprising detector arrays which may be electronically manipulated through a computer system. The detection system, by providing the ability for electronic manipulation, permits adaptive imaging. Detector array configurations include familiar geometries, including slit, slot, plane, open box, and ring configurations, and customized configurations, including wearable detector arrays, that are customized to the shape of the patient. Conventional, such as attenuating, rigid geometry, and unconventional collimators, such as x-ray optic, configurable, Compton scatter modules, can be selectively employed with detector modules and radiation sources.

Abstract: A method of generating EUV radiation is described, comprising the steps of: transporting a solid medium (33) through a source space (34) connected to a vacuum pump (35), and irradiating a portion (37) of the medium with an intense, pulsed, laser beam (41) focused on said portion of the medium, thus creating a plasma (47) which emits EUV radiation. To increase the intensity of the EUV radiation and improve the possibility to collect particles (51, 52, 53) released from the medium, at least the medium portions (37) to be irradiated have a concave shape. The method can be improved by embedding the medium in a flow of rare gas. Also described are a EUV radiation source unit for realizing the method and the application of the method in the manufacture of devices such as IC devices, and in a lithographic projection apparatus.

Abstract: A method for calibration and/or quality assurance of nuclear medicine imaging, in which functional information of the organs to be studied is achieved by inserting radioactive solution emitting detectable radiation in the organs of a phantom simulating the organs to be studied and by detecting the radiation. The filling and emptying of the organs of the phantom to be studied is simulated by regulation of the detectable radiation from the phantom. The organs to be simulated by the phantom are in form of containers filled with radioactive solution, the apparatus further comprising movable isolating parts, like steel plates, between the containers and the gamma camera to isolate radiation from the containers to the camera. The invention is also concerned with an arrangement comprising the apparatus of the invention and a gamma camera.

Abstract: A method for detecting ionizing radiation, a detector (64) for detection of ionizing radiation, and an apparatus for use in planar beam radiography, including the detector. The detector includes: a chamber filled with an ionizable gas; first and second electrode arrangements (2, 1, 18, 19) provided in the chamber with a space between them, the space including a conversion volume (13); an electron avalanche amplification unit (17) arranged in the chamber; and, at least one arrangement of read-out elements (15) for detection of electron avalanches. Radiation enters the conversion volume between the first and second electrode arrangements via a radiation entrance. The distance between the first and second electrode arrangements is selected to achieve discrimination of fluorescent photons and/or long-range electrons, in order to achieve improved position resolution.

Abstract: One embodiment of the present invention is a method for constructing a post-patient collimator for a computed tomographic (CT) imaging system, the method including steps of: edge welding collimator plates to a top rail using at least one directed energy beam welder; and edge welding the collimator plates to a bottom rail, using the at least one directed energy beam welder. The above described embodiment provides an efficient and less expensive method for manufacturing a post-patient collimator for a CT imaging system than embodiments requiring use of precision combs for accurately positioning the plates.

Abstract: One embodiment of the present invention is a method for constructing a post-patient collimator for a computed tomographic (CT) imaging system, the method including steps of: edge welding collimator plates to a top rail using at least one directed energy beam welder; and edge welding the collimator plates to a bottom rail, using the at least one directed energy beam welder.

Abstract: A collimator having slits of varied widths, wherein each slit includes a curved side profile having a common axis of curvature for providing a cross-section of an emitted beam of energy with a substantially uniform width when the common axis of curvature of the slit intersects a focal spot of a source of the beam. The collimator is curved about a rotation axis substantially normal to the common axis of curvature, such that rotating the collimator about the rotation axis will sequentially position the slits to collimate the emitted beam.

Abstract: Collimator apparatus is provided for an X-ray imaging system comprising an X-ray tube disposed to project an X-ray beam, and a detector spaced apart from the X-ray tube for receiving X-rays of the beam within an Active Imaging Area (AIA). The apparatus comprises a first collimator positioned along the path of the beam, the first collimator being vertically adjustable, and being operable to symmetrically collimate the beam. The apparatus further comprises a second collimating device positioned between the first collimator and the detector. The second collimating device limits the uppermost rays of the symmetrically collimated beam which reach the detector to a predetermined upper boundary. Thus, the second collimating device serves to fix the upper edge of the AIA on the detector.

Abstract: A collimator system including a plurality of revolvable plates stacked one above another, the plates being constructed of a material substantially impervious to passage therethrough of radiation in a predetermined range of wavelengths, and at least one collimator aperture formed in each of the plates.

Abstract: A fluorescent X-ray analyzer includes a detector (6) for detecting fluorescent X-rays (5) emitted from a sample piece (1) to be analyzed, and a first collimator (10) disposed between the sample piece (1) and the detector (6) supported for movement between inserted and retracted positions with respect to a path of travel of the fluorescent X-rays (5) towards the detector (6). The first collimator (10) comprises a wall (11) adjacent the sample piece (1) that is stepped to provide stepped wall segments (11a, 11b, 11c) having respective apertures (12a, 12b, 12c) of varying diameters defined therein. The smaller the aperture, the closer it is to the sample piece (1) when one of the apertures (12a, 12b, 12c) is selected according to a size of a target area of the sample piece (1) to be measured and is then brought in register with the path of travel of the fluorescent X-rays (5) towards the detector (6).

Abstract: A radiosurgery and radiotherapy system to provide diagnostic imaging and target localization via a patient 3-D mapping means such as a CT scanner or MRI, patient positioning via a four degree of freedom of motion table, and a stereotactic Cobalt 60 therapy unit incorporating multiple sources to therapeutically irradiate a target is provided. Methods of radiosurgery and radiotherapy utilizing the system are also provided. A combination of radiation source configuration, 360 degree rotational characteristics of the therapy unit, and table movement will allow any size and shape of target to be irradiated to therapeutic levels while decreasing radiation exposure to surrounding healthy tissue. A radiation beam catcher which captures greater than 80% and preferably greater than 90 percent of the radiation from the radiation sources is also provided.

Abstract: Process for determining the configuration or configurations [treatment time (TT.sub.i)/diameter (.phi..sub.i,f) of each collimator] of a helmet for stereotactic radiosurgery, to which can be fitted an plurality of collimators focused on an irradiation isocenter, consisting in automatically optimizing, through iterative dose calculation, the dose (D.sub.p) received at predetermined optimization points (M.sub.p), by modifying, in the course of the successive iterations, the treatment time (TT.sub.i) of at least one shot (i) and the diameter (.phi..sub.i,f) of at least one collimator (C.sub.f) of at least one shot (i), and by calculating, at each iteration, an objective function (OF) having as variables the differences between the calculated dose (D.sub.p) and the expected dose (ED.sub.p) for each point of optimization (M.sub.p), iterative calculation of the doses being carried out automatically until the objective function (OF) satisfies a predetermined optimization criterion.

Abstract: The present invention discloses a process for converting the beam diameter of radioactive rays and a radiating unit used in a medical stereotactic radiotherapeutic apparatus. Over a collimator base (11) symmetrical about a central axis are distributed a number set of collimators (1) of different aperture diameter. The rule of distribution of each set of collimators is the same as that of the radioactive sources (2) in the source base (4). The collimator base (11) can be rotated according to the requirement of the therapy to make a set of collimators (1) of a certain aperture diameter in alignment with the radioactive sources (2). Thus it is possible to alter the size of the beam diameter of radioactive rays. The advantages of the invention are convenience in operation, enhancement of the accuracy of positioning and the easiness of putting into practice the automatic control by a computer.

Abstract: This invention relates to a novel dynamic collimator which can be adapted to a linear accelerator (LINAC). The collimator is such that the shape of the jaw arrangement, and therefore the collimated beam of X radiation from the LINAC, can be changed and conformed in a very flexible and versatile way. In a preferred embodiment of the invention, the collimator has three pairs of opposing, parallel jaws, each pair of jaws being moveable, under control, to open and close in variable amounts. Each set of pairs may be oriented at a 60.degree. orientation such that the open transmission area of the collimator has a hexagonal shape. Variations on this sixth jaw collimator, including larger numbers of jaws, also are included within the invention. The variety of shapes with such a variable hexagonal collimator is enormous. Irregular target volumes can be filled by beams of radiation that can be nested because of the hexagonal nature of the jaw configuration, giving it added conformal shaping capabilities.

Abstract: A radiosurgery and radiotherapy system to provide diagnostic imaging and target localization via a patient 3-D mapping means such as a CT scanner or MRI, patient positioning via a four degree of freedom of motion table, and a stereotactic Cobalt 60 therapy unit incorporating multiple sources to therapeutically irradiate a target is provided. Methods of radiosurgery and radiotherapy utilizing the system are also provided. A combination of radiation source configuration, 360 degree rotational characteristics of the therapy unit, and table movement will allow any size and shape of target to be irradiated to therapeutic levels while decreasing radiation exposure to surrounding healthy tissue. A radiation beam catcher which captures greater than 80% and preferably greater than 90 percent of the radiation from the radiation sources is also provided.

Abstract: An automatic collimator exchanger for a gamma camera system for simultaneous exchange of pairs of collimators (or a single collimator) for a dual detector head system. The present invention includes an exchange assembly having an elevator, a carriage and a bridge. The elevator includes a rack of multiple parallel and stacked trays for holding various pairs of collimators. A draw bridge unit is attached to one side of the elevator (which side faces a gantry structure) and may extend into the gantry structure. The carriage is able to support two collimators and moves from within the elevator unit onto the bridge and into the gantry structure, when the bridge is lowered, to position between two aligned detector heads of the dual head gamma camera system. When the detector heads are positioned near the aligned carriage, latch pins are released and collimators may be transferred to the carriage, if empty, or hastened to the detector heads from the carriage when installing a pair of collimators.

Abstract: A toroidal x-ray tube (I) is supported and selectively positioned by a gantry (II). The x-ray tube includes a toroidal housing (A) in which a rotor (20) is rotatably mounted. One or more cathodes (C) are mounted on the rotor for generating an electron beam which strikes an anode (B) to generate a beam of x-rays which pass through a patient aperture (62) to strike a detector (60). The x-ray tube includes pre-collimators (70, 74) having slots (72, 76) for passage of the x-ray subsequent to generation thereof and prior to being collimated by the collimator (90). A ring collimator (90) collimates an x-rays formed into a fan shaped beam. The collimator (90) includes a first ring (92) and a second ring (94) which are concentric. The distance between the first and second rings (92, 94) is adjustable to adjust the slice thickness of the final image.

Abstract: A collimator for a gamma camera is formed by a stack of lamina formed from tungsten. Each lamina has an array of openings formed through it, and a movable support member translates the lamina into different alignments of these openings to form corresponding different hole patterns through the collimator.

Abstract: An X-ray fluorescent spectrometer uses a screen which restricts a field of view to a local portion of a specimen irradiated by X-rays from an X-ray tube. Fluorescent X-rays from the specimen from the local portion and passing through the screen are collimated, dispersed and analyzed. A control unit controls a rotating mechanism to rotate the specimen or its container around a predetermined axis and also a moving mechanism to linearly move the screen such that the local portion to be analyzed and a throughhole of a proper size therefor can be brought adjacent each other. Data on the positions of local portions to be analyzed on the specimen can be inputted through an input unit. Effects of variations in detection results due to different distances between the analyzed local portions and the axis of rotation can be compensated for by storing reference data obtained from a standard sample in a data processing unit.

Abstract: Radiation is generated toward a patient. A radiographic region of the radiation covers a predetermined field-of-view. Both of a stereotactic radiation producing filter and a radiographic radiation producing filter are transported in such a way that the stereotactic radiation producing filter and the radiographic radiation producing filter sequentially intercept the beam axis between the patient and a generation position for the radiation. When the stereotactic radiation producing filter is located on the beam axis, it forms the radiation into radiation required for stereotactic radiosurgery. When the radiographic radiation producing filter is located on the beam axis, it forms the radiation into radiation required for radioscopy. Radiation present within the radiographic region is detected with employment of a radiation detecting unit positioned opposite to the generation position of the radiation with respect to the patient.

Abstract: A transfer system is provided to effect collimator change out for a medical nuclear camera. The system includes a rectangular lead collimator frame into which the collimator is mounted. The collimator frame has an outer peripheral edge and an inner peripheral edge, the peripheral edges defining the collimator thickness. A transfer cart has a C-shaped transfer frame carrying top, bottom and side supports. The top and bottom supports have spring biased locking discs protruding therefrom which are adapted to contact and lock into contact grooves formed into the collimator frame's outer peripheral edge at its top and bottom thus encapsulating the collimator frame within the transfer cart frame for movement of the camera to storage and vise-versa. An especially configured storage rack is provided which has vertically extending, rack modules for storage/retrieval of the collimators.

Abstract: In order to perform stereoradiography, an X-ray apparatus utilizes an X-ray tube having a pair of X-ray focal points. The X-ray beams are alternately irradiated from the focal points toward an image intensifier through a patient and are limited by an X-ray beam limiting device. The device shapes the irradiated X-ray beams onto a circular detection surface of the image intensifier into a polygon such as octagon. The X-ray irradiation field on the detection surface can be circumscribed to a circular input window (i.e. effective input area), preventing the field from going beyond the detection surface. Thus, direct X-ray leaking over the image intensifier is avoidable.

Abstract: A system for applying radiation treatment under computer control is disclosed. The system has a radiation source, which generates a variable intensity radiation beam, and a collimator. The collimator has a plurality of movable plates disposed in the path of the radiation beam and is oriented in a direction perpendicular to the beam axis. The apparatus is capable of actuating the plates independently during the radiation treatment, in response to a first control signal. The beam changes in width when the plates are so actuated. The collimator is rotated in response to a second control signal. The intensity of the radiation beam may be varied as a function of the plate position. A total radiation dosage is applied during two intervals. The first interval precedes the collimator rotation, and the second interval follows the rotation.

Abstract: A scintillation camera includes a plurality of detectors mounted on the camera and arranged to provide an opening for allowing the insertion of an object for examination such as a human being and for radiographing a tomographic image, a plurality of collimators each of which is attached to the front of the corresponding detectors for collimating X-rays radiating from the object for examination, and an exchanger for the collimators, the exchanger including a carrier and a holding device for holding the collimators in a swingable manner in any direction within a certain range by use of a mechanism such as a spherical bearing.

Abstract: A device for examining a test object (4) by means of gamma or X-rays, comprising a primary X-ray source for generating at least one primary X-ray pencil beam (3) which is directed onto the test object (4), and at least one slit diaphragm (8, 9) which is arranged between the test object (4) and a detector (6, 7) and which directs scattered X-rays (26, 27, 28, 29) produced by the primary X-ray beam (3) in the test object (4) onto at least one detector (6, 7). The depth range of the test object that can be covered by the detectors can be changed without changing the position of the test object or the examination device, in that the position of the slit diaphragm (8, 9) relative to the detector (6, 7) can be changed by means of an adjusting device (18, 19).

Abstract: The nuclear scintillation camera system has an improved positioner including a drum which is rotatable on a frame which may be linearly moved along a track. The camera is cantilevered to the drum and is able to rotate about the axis of the cantilever as well as about an axis perpendicular to the axis of the cantilever and parallel to the plane of the camera crystal. The frame may be moved along the track with the camera in a given position for doing linear body scans, and with the patient positioned along the axis of the drum, scans around the patient may be carried out for emission computed tomography (ECT). The system also provides a collimator changer stand for exchange and storage of collimeters for use with the nuclear scintillation camera. The system according to the invention makes nuclear scintillation imaging easier to carry out.

Abstract: An outer gantry (20) is movably mounted on wheels to move along tracks (22). An inner gantry (30) rotatably mounted on the outer gantry includes at least a pair of guide rods (56, 58) on which detector heads (32, 34) are slidably mounted. Motors (92, 102) selectively translate the detector heads along the guide rods. A chain and sprocket arrangement (116, 114; 128, 126) constrains the heads against canting and maintains opposite sides of the detector heads in alignment as the detector heads move and as the inner gantry rotates. Each detector head includes a roller bearing track or channel portion (140) on which a horizontal track portion (142) of a collimator (144) is hung vertically. A collimator connecting assembly (150) connects a bottom portion of the collimator to the detector head and secures it against further horizontal movement.

Abstract: A gamma camera of the invention fitted with a pin-hole cone for acquiring photographic type images, i.e. having a tungsten end fitting disposed at the small end of a truncated cone and provided with a pin-hole therethrough, is suitable for forming a point image of an object to be observed on the basis of gamma radiation emitted therefrom, transmitted through the pin-hole and magnified on reaching the inlet to the scintillator. The truncated cone is modular in structure: the pin-hole cone is mainly constituted by a base, a first truncated cone of suitable thickness for stopping low energy gamma radiation, and a second truncated cone superposable at will on the first so that the assembled cones are of sufficient thickness to stop high energy gamma radiation.

Abstract: A fluorescent X-ray film thickness gauge having an X-ray source for generating incident X-rays, a shutter device for shuttering the incident X-rays, a collimator for collimating the incident X-rays, a sample stage for mounting a sample onto which the collimated X-ray is irradiated, and a detector for detecting fluorescent X-rays generated from the sample upon irradiation of the collimated X-rays. The shutter device includes a switching mechanism operable to switch the shutter device between a measurement state and a calibration state, a shutter frame, and a shutter member disposed in the shutter frame and having a measurement passage, a calibration passage and a calibration plate in the calibration passage.

Abstract: A body is scanned by a fan-shaped X-ray beam for an X-ray shadow image. Per sector of the fan-shaped X-ray beam detection means deliver a signal which is a measure of the quantity of X-ray radiation instantaneously transmitted in the respective sector through the body. An attenuation device operates in conjunction with a slit-type diaphragm and regulates the quantity of X-ray radiation transmitted under the control of control signals per sector of the fan-shaped X-ray beam. The control signals are formed on the basis of the signals from the detection means. The attenuation device comprises one or more elastic X-ray radiation absorbing strips extending essentially parallel to the slit-type diaphragm. The attenuation device comprises controllable drive members to bring the strip or strips to an undulated state.

Abstract: Disclosed is a radiology system of the mammography type wherein there is provision for a radiation controller having a detector of X-radiation having gone through the breast to be observed, of the type having a converter of X-radiation into photon radiation and a photomultiplier tube for the amplifications of photons emitted by the converter. The invention lies in the fact that the converter is masked by a belt opaque to the photon radiation except in the zones for which variable dimensions are planned so as to get adapted to the different shapes of breasts. The belt is driven by a motor which is turned on and off at the practitioner's command, so that the appropriate zone is in correspondence with the converter.

Abstract: An exposure compensation apparatus for use in a radiographic equipment to modulate local intensity of radiation. The exposure compensation apparatus comprises a detecting means to detect transmittance of radiation at a location of a radiated object, right-left reversion means to reverse a location arrangement of the transmittance data on a line of a predetermined direction, an averaging means to average a pair of the original and reversed transmittance data of a location to acquire an averaged transmittance, and a local intensity control means to control a local intensity compensation means of the radiographic equipment.

Abstract: A measurement device for on-line measurement of the gamma radiation emitted by the water in a nuclear reactor circuit, in particular the primary cooling circuit of a pressurized water nuclear reactor, the measurement device comprising:at least one volume (101, 102) for metering the fluid to be analyzed;a radiation detector (200) placed facing the volume; and a collimator interposed between the volume and the radiation detector, the collimator being constituted by a plurality of collimators (431, 432, 433) of different sizes mounted on a common member (400) which is movable relative to the volume-and-detector assembly, with the position of the moving member being determined automatically as a function of the measurement signal delivered by the detector so that the greater the intensity of the radiation revealed by the delivered signal, the smaller the size of the collimator interposed between the detector and the volume.

Abstract: A measuring apparatus (10) for measuring the thickness of a coating on a workpiece (36) by X-ray fluorescence. The apparatus includes a frame (12) upon which is mounted an X-ray tube (14), a shutter (16), first collimator means (18), and a mirror (20) through which an X-ray beam may be projected. Also mounted on the frame (12) is a signal detector (26), which may be in the form of a proportional counter, a fixed focal length viewing device (28) which is capable of viewing a workpiece through the mirror, and a work holder (34) carried by a work holder mount (32) which is capable of moving the workpiece (36) in x, y and z orientations. The apparatus is further provided with a second collimator means (48) shiftable by a moving apparatus (53) from an inoperative position to an operative position wherein a second collimator (50) is disposed between the mirror and the workpiece in such a manner that the terminal end (51) of the second collimator is as close as possible to the coating on the workpiece.

Abstract: An x-ray tube is enclosed in a housing 14, with a detachable x-ray cone 22 having an outward extending flange member 42, a cone holder 18 for receiving the flange member 42, a latch button 50 projecting from the holder for selectively releasing the cone 22 from the holder 18, and a safety plate assembly 26. The safety plate assembly is mounted between the cone holder and the housing 14 and has first and second tabs 28 which project from a periphery of a planar portion 30 of the safety plate substantially at right angles therewith. Each tab 28 has a projection 34 that is directed inward toward the other end generally at right angles with the tabs whereby a resting place is provided for the released cone 22 until the cone is manually removed.

Abstract: A dental x-ray diagnostics installation having a holder for film cassette and a holder for diaphragms of different sizes, which holder for diaphragms is positioned in an x-ray source so that the beam passes through the diaphragm aperture before reaching the subject. The diaphragms are interchangeable with one another and have different diaphragm apertures for the purpose of matching the x-ray beam cross-section to different film cassette formats.

Abstract: An X-ray fluorescence thickness measuring devise includes a primary X-ray beam collimation and workpiece positioning system that markedly increases the detectable fluorescent X-radiation from diverse specimen calibration standards and workpieces subjected to measurement. The positioning system includes an optical viewing system that provides a video signal image of the specimen surface prior to and during specimen radiation without hazard to the unit operator and independent of the collimator bore selected. A further feature of the measuring device is that it includes a system which assures repetitive and accurate positioning of a selected collimator relative to the axis of the X-ray beam to obtain maximum beam transmission therethrough.

Abstract: A method and an apparatus for the radiographic recording of a patient's dentition, jaws, and skull regions invalues seating a patient in a patient chair (9) so as localize the patient in the coordinate system of the radiographic apparatus in an unequivocal position before taking the exposure for a radiograph (87). Furthermore, in accordance with the invention, the radiograph (87) is used for measuring the coordinates of a desired object (95) by a coordinate locator (88), after which the desired partial area (94 or 96) is selected on the basis of the coordinates, and the exposure direction is changed in relation to the first exposure in the horizontal plane and/or the vertical plane before executing the exposure program for the desired partial area (94 or 96).