Abstract: A whole body x-ray bone densitometry system includes a table extending parallel to a Y-axis of an XYZ coordinate system for supporting a patient at a patient position; an x-ray source for emitting a narrow angle fan beam of x-rays to irradiate at any one time a scan line which is transverse to the Y-axis and is substantially shorter than the width of a body cross-section of a typical adult patient occupying the patient position. An x-ray detector is aligned with the source along a source-detector axis which is transverse to the Y-axis, for receiving x-rays from the source within the angle of the fan beam after passage thereof through the patient position. The detector has a number of detecting elements arranged along a direction transverse to the Y-axis and to the source-detector axis.

Abstract: An x-ray imaging system according to the present invention comprising a stepped scanning-beam x-ray source and a multi-detector array. The output of the multi-detector array is input to an image reconstruction engine which combines the outputs of the multiple detectors over selected steps of the x-ray beam to generate an x-ray image of the object. A collimating element, preferably in the form of a perforated grid containing an array of apertures, interposed between the x-ray source and an object to be x-rayed. A maneuverable positioner incorporating an x-ray sensitive marker allowing the determination of the precise position coordinates of the maneuverable positioner.

Abstract: Radiological apparatus, such as a bone densitometry measurement system, utilizes a penetrating radiation source, such as an x-ray source. The apparatus has a multi-position attenuator mechanism for placement of different attenuating materials in the radiation beam. The mechanism includes a rack of attenuating materials which is translated across the radiation beam path by a drive mechanism, such as a linear motor. The mechanism preferably includes a controller for actuating the drive mechanism in response to operator command and monitoring which attenuating material crosses the beam path by way of position signals generated by a position encoder that is coupled to the controller. This attenuator mechanism allows attenuating materials to be stored within the radiological apparatus, enables operator selection of attenuating materials under automatic machine control and self-alignment of the material relative to the radiation beam.

Abstract: A universal radiographic/fluoroscopic "room" is constructed according to the present invention by combining a versatile group of X-ray examination system components, electrical and mechanical drive components, and sensing components, under the supervision of a flexible control system, to form a universal diagnostic medical imaging system capable of performing radiographic, fluoroscopic, tomographic, and stepped examinations in several different operator-selectable configurations. The operator selects any available operating mode, including auto-bucky, auto-wall, auto-table, auto-table/wall, servo-tomo, conventional stepping, stepped-digital, auto-step, and auto-step-center modes, using a a control panel. The control system automatically determines which system components are required to perform that type of examination, moves the components into operational or storage positions as required, and prepares each component for operation. The operator need not manually reconfigure the equipment.

Abstract: An x-ray imaging system according to the present invention comprising a stepped scanning-beam x-ray source and a multi-detector array. The output of the multi-detector array is input to an image reconstruction engine which combines the outputs of the multiple detectors over selected steps of the x-ray beam to generate an x-ray image of the object. A collimating element, preferably in the form of a perforated grid containing an array of apertures, interposed between the x-ray source and an object to be x-rayed. A maneuverable positioner incorporating an x-ray sensitive marker allowing the determination of the precise position coordinates of the maneuverable positioner.

Abstract: A multiple x-ray energy level imaging system includes a scanning x-ray beam and two detector design having a first low x-ray energy sensitive detector and a second high x-ray energy sensitive detector. The low x-ray energy detector is placed next to or in front of the high x-ray energy detector. The low energy sensitive detector has small stopping power for x-rays. The lower energy x-rays are absorbed and converted into electrical signals while the majority of the higher energy x-rays pass through undetected. The high energy sensitive detector has a large stopping power for x-rays as well as it having a filter placed between it and the object to absorb the lower energy x-rays. In a second embodiment; a single energy sensitive detector is provided which provides an output signal proportional to the amount of energy in each individual x-ray it absorbed. It can then have an electronic threshold or thresholds set to select two or more energy ranges for the images.

Abstract: An x-ray imaging system according to the present invention comprising a stepped scanning-beam x-ray source and a multi-detector array. The output of the multi-detector array is input to an image reconstruction engine which combines the outputs of the multiple detectors over selected steps of the x-ray beam to generate an x-ray image of the object. A collimating element, preferably in the form of a perforated grid containing an array of apertures, interposed between the x-ray source and an object to be x-rayed. A maneuverable positioner incorporating an x-ray sensitive marker allowing the determination of the precise position coordinates of the maneuverable positioner.

Abstract: The system of the present invention uses x-rays having a narrow fan beam to scan patients for bone density and soft tissue body composition measurement and imaging. In addition to single pass scanning of body parts such as the spine, hip and forearm, a method for multiple pass whole body scanning is provided. The system includes a movable scan table configured to support a patient and a C-arm associated with the table. The C-arm is configured to support an x-ray source in opposite to an x-ray detector at opposite sides of the patient. A scanning mechanism is provided to move the scan table and C-arm to scan the patient with overlapping adjacent x-ray fan beams in successive scan passes along the length of the patient. A scan pass combination scheme that blends areas of overlap is employed to compensate errors related to height dependency. The blending is performed according to the height of the part of patient scanned in the overlap and the distance from the edge of the scan pass.

Abstract: In a computed tomography imaging system, wherein a longitudinally-unbounded object is oriented with respect to a source of cone beam radiation and a detector array, a method is provided for reconstructing an image of the longitudinally-unbounded object. Initially, relative movement between a longitudinally-unbounded object and the cone beam source is established along at least one circular scan path and at least one linear component. The cone beam is operated to irradiate measurable regions of the object while a prescribed orbit is traversed, to project an image of the longitudinally-unbounded object as cone beam data, onto the detector array. A scan field of view is defined, relative to the cone beam geometry. An error propagation distance in a Z direction is determined for the scan. The definition of the scan field of view is then modified, according to error propagation distance, and a set of image reconstruction data is generated, within the modified field of view, from the circular and linear scan paths.

Abstract: Best scan parametric values of a x-ray bone densitometry scanning system for a particular patient is selected according to a thickness of the patient. An operator initially selects scan parametric values of a fast mode scan which is the recommended default, and then commences the fast mode scan. At the initial portion of the scan, the x-ray thickness of the patient is measured. If the measured x-ray thickness is not greater than a predetermined limit of the fast mode scan, the fast mode scan is continued. If the measured x-ray thickness is greater than the predetermined limit of the fast mode scan, the x-rays are turned off, and the operator is given a choice of continuing with the fast mode scan or restarting with a slower mode scan. If the operator selection is to continue, the fast mode scan is continued. If the operator selects restarting, a slower mode scan is commenced.

Abstract: A patient is positioned on a patient support (12) and a gantry (16) carrying an x-ray source (10) and a radiation detector assembly (14) are rotated around the subject. The detector assembly includes a video camera (28) which is run in a synchronous mode to generate a first plurality of images at regular temporal intervals T.sub.blanking. Because each image requires a finite time for generation, it is acquired over an interval of arc between a starting angular orientation (A.sub.S .degree., B.sub.S .degree.) and a terminal angular orientation (A.sub.T .degree., B.sub.T .degree.). A position encoder (40) monitors the terminal positions of each of the first series of images. The patient is then injected with a radiographic dye and the gantry is rotated in a reverse direction. A comparator compares the stored terminal angular positions of each forward direction image and the current angular position of the gantry.

Abstract: An X-ray computerized tomography apparatus includes n number of X-ray detector arrays. Each of X-ray signals detected by the detector arrays during helical scan is stored associated with an angle of a rotating gantry and the position of a top board. Also, each of the X-ray signals is stored associated with an angle differing by 180 degrees and the corresponding position of the top board. A pair of first and second X-ray signals for the same angle of the gantry is selected for each of predetermined angles ranging from 0.degree. to 360.degree.. The first X-ray signal corresponding to the first position closest to the position of a plane section of a subject under examination and the second X-ray signal corresponding to the second position that is closest to the position of the plane section on the opposite side of the first position for the first X-ray signal with respect to the position of the plane section are subjected to weighted-averaging according to their distance from the position of the plane section.

Abstract: A computed-tomography apparatus acquires a cross-sectional image of an object from projection data obtained by scanning the object with radiation while rotating a scanner around the object. One of rotation positions of the scanner having a smaller attenuation of radiation is determined. The operation of the scanner is controlled to start the scan from the rotation position having the smaller attenuation. Individual weights are assigned to projection data in a predetermined rotation angle range near a scan start rotation position of the scanner and near a scan end rotation position thereof and projection data in a rotation angle range opposite to the predetermined rotation angle range, respectively. The weighted projection data and unweighted projection data are used for determining corrected data for the entire circumference of the object to generate a cross-sectional image based thereon.

Abstract: A medical X-ray imaging apparatus is provided, which comprises an X-ray source, an X-ray imaging device for detecting an image of X-rays having passed through a subject and a swivel member for-rotating the X-ray source and the X-ray imaging device around the subject. The X-ray imaging device comprises a CCD sensor for performing the TDI operation and a dosage sensor for detecting X-rays having passed. Dosage signal Y and transfer speed signal X corresponding to the frequency of a false vertical transfer clock are supplied to a divider, and control signal Z is outputted. When control signal Z is supplied to an X-ray control circuit via a delay circuit, the X-ray irradiation dosage of the X-ray source can be feedback-controlled properly.

Abstract: A tangential computer tomography scanner for scanning an object having a cross-section. A radiation source emits a beam of penetrating energy. The beam penetrates an object located within the beam and is received by an array of detectors located opposite the source. A drive device moves the beam relative to said object. The array and the source are arranged so that the beam is maintained perpendicular to the cross-section of the object. The tangential computer tomography scanner generates a full volume data set in a single pass.

Abstract: An x-ray imaging system according to the present invention comprising a stepped scanning-beam x-ray source and a multi-detector array. The output of the multi-detector array is input to an image reconstruction engine which combines the outputs of the multiple detectors over selected steps of the x-ray beam to generate an x-ray image of the object. A collimating element, preferably in the form of a perforated grid containing an array of apertures, interposed between the x-ray source and an object to be x-rayed. A maneuverable positioner incorporating an x-ray sensitive marker allowing the determination of the precise position coordinates of the maneuverable positioner.

Abstract: A radiographic inspection apparatus for large containers, vehicles and structures having a movable frame which can straddle the container or object being inspected. The straddling frame has opposed parallel sides which carry a source of penetrating radiation and a detector array. The source or sources and detectors are moved along the length of a container while radiographic image data is being sequentially recorded. By summing or collecting the sequence of data over the length of a container as the straddling frame moves along, a full two-dimensional radiographic image of the container may be obtained. Radiographic images may be enhanced either by providing uniform motion for the straddling frame or by measuring non-uniform motion and compensating corresponding regions of the radiographic image.

Abstract: A slit radiography apparatus is provided with an absorption device comprising electrically controllable piezoelectric tongues. Upper and/or lower deflections of the tongues are limited to a maximum by trips outside the X-ray fan beam. More than one strip can be present as seen in the length direction from the fixed ends of the tongues Thus deflections of the tongues are limited and great phase changes in the control signals without resultant oscillations can take place during the time the tongue are restricted in their movement by the strip.

Abstract: A scan speed procedure and method wherein a minimum radiation exposure period is determined on an object by object basis for a transmission study. Two transmission scans are performed including a prescan followed by a second transmission scan phase. The first transmission prescan is performed using a radiation source over the object. This prescan is of a rapid and predetermined duration (Tp). A resultant count density associated with the object is then generated and examined. The portion having the smallest count density (Cm) is determined and a value (Co) representing the minimum required number of counts for transmission study is given. From the above, a transmission period (Ts) is determined by the system and the second transmission scan phase is performed for the duration Ts using a multi-pass scan phase.

Abstract: A scan-type X-ray imaging system and method are disclosed. Image detection is effected by use of a fixed phosphor converter screen covering the entire field of view so that X-rays passed through an object, or a body portion, positioned at a scan area, are received at the converter screen and light signals, proportional to the received X-rays, are coupled through a movable coupler, having an input portion movably engaging the converter screen, to a movable sensor that converts received light signals to electrical output signals indicative of the object, or body portion, then at the scan area.

Abstract: Methods and apparatus for performing a computed tomography scan are described. In one embodiment of the apparatus, a twin beam computed tomography scanner includes a beam splitter, an x-ray source for generating an x-ray to be projected generally towards, and at least partially through, an object, and a detector array comprising a plurality of detector cells arranged to form at least two cell rows. The beam splitter is positioned so that the x-ray projected from the x-ray source is substantially split to form at least two beams prior to being projected at least partially through the object.

Abstract: A slit radiography apparatus is provided with an absorption device comprising electrically controllable piezoelectric tongues. Upper and/or lower deflections of the tongues are limited to a maximum by trips outside the X-ray fan beam. More than one strip can be present as seen in the length direction from the fixed ends of the tongues. Thus deflections of the tongues are limited and great phase changes in the control signals without resultant oscillations can take place during the time the tongue are restricted in their movement by the strip.

Abstract: A transfer magnification correcting method suited for use in scanning exposure by use of synchrotron radiation or the like. In proximity exposure according to the scanning exposure method by use of synchrotron radiation, the magnification in the scanning direction is corrected by relatively moving a wafer and a mask simultaneously with the scanning. Also, the overall correction of the magnification is performed by changing a proximity gap or adjusting the temperature of the mask or the wafer. As a result, it is possible to correct the transfer magnification separately in the vertical and horizontal directions.

Abstract: The invention relates to a medical imaging device using X or gamma ionizing radiation. It comprises a source (S) of radiation in a divergent beam, and a longitudinal slit (F) delivering a sheet-form beam in a plane containing the slit (F). A detection module (1) is provided, which comprises a drift chamber (12) and a multiwire chamber which are filled with a gas. The chambers comprise, in a direction orthogonal to the plane containing the slit (F), the drift space (12) for the electrons, comprising a cathode electrode (11), a converter (121), a proportional multiplier anode (13) for generating multiplied electrons and corresponding ions, and a second cathode electrode (14), placed in the vicinity of the multiplier anode (13). The multiplier anode (13) and the second cathode electrode (14) consist of conductor elements extending in two parallel planes, along substantially orthogonal directions, in order to permit two-dimensional localization of the electrons in this plane.

Abstract: An X-ray apparatus for collecting X-ray transmission data of a subject from a plurality of directions to generate an X-ray transmission image or X-ray CT image of the subject, which includes an X-ray generator for generating an X-ray, an X-ray detector for detecting a transmission X-ray after the X-ray generated by the X-ray generator is transmitted through the subject, a rotation unit for rotating an imaging unit including the X-ray generator and the X-ray detector around the subject, a data collector for converting an output signal of the X-ray detector to a digital signal and collecting the digital signal, a signal processor for subjecting data collected by the data collector to a signal processing operation, a display for displaying thereon as an image the data collected by the data collector and the data subjected by the signal processor to the signal processing operation, and a position change unit for moving a relative position of a rotation center of the imaging unit and the subject in a direction par

Abstract: An imaging system for medical and industrial applications that includes scanning a plurality of points of the object zone with an intermittent collimated radiation incident beam, producing a series of first digital signals representing the energy of said beam that transmits through corresponding points of the zone along the incident line, producing a series of second digital signals representing the energy of said beam scattered off the incident line by the object, storing the informational content of the first and second digital signals contents to represent an incident image array and a scattered image array, and combining the information contents of substantially corresponding points of said arrays to produce a visual image display that is more accurate than either of the first and second image arrays alone. High and low energy beams can be used and three dimensional or depth information can also be derived.

Abstract: A radiographing operation is performed by using an X-ray CT apparatus for performing a radiographing operation to a subject lying on a bed, which comprises a bed drive means, an X-ray tube irradiating an X-ray to the subject, a detecting means for detecting an irradiated X-ray, a gantry on which said X-ray tube and said X-ray detecting means are mounted, a gantry drive means for rotationally driving the gantry, an exposure information file means into which past exposure information for the subject is stored, and a main controller for controlling the X-ray tube, the bed drive means and the gantry drive means. The radiographing condition according to which the radiographing operation is performed is set in accordance with a past exposure information stored in the exposure information file and at least one of the bed, the X-ray tube and the gantry.

Abstract: Method and apparatus for generating a large-field, high-resolution digital image of an object by sequentially generating multiple optical scenes representative of different portions of the object, and then sequentially directing each optical scene onto an optical detector to generate multiple sub-images of the different portions of the object. Each scene is induced using a separate X-ray sub-beam, each of which is generated by spatially filtering a portion of an incident X-ray field with a spatial filter moving in concert with the scene-directing device. Once generated, the sub-images are combined to form the large-field, high-resolution image.

Abstract: A medical imaging device using X- or gamma ionizing radiation, provided with a source of radiation in a divergent beam diaphragmed by a slit and a module for detecting a beam transmitted by a body to be observed, illuminated by the beam. The detection module comprises a drift chamber and a multiwire chamber which are filled with a gas, these chambers comprising, in a direction orthogonal to the plane containing the slit and the illumination beam, a drift space for the electrons, an electron proportional multiplier grid for generating multiplied electrons and corresponding ions and a second cathode electrode making it possible to count the multiplied electrons by means of the corresponding ions for a plurality of directions of the sheet-form illumination beam.

Abstract: An x-ray diagnostics installation for producing x-ray exposures of body parts of a patient has a line detector camera arranged diametrically opposite a radiation source, the line detector camera containing an x-ray detector arranged behind a slot-shaped opening, the width of the x-ray detector being matched to the width or length of the body part to be registered. An adjustment system adjusts the line detector camera relative to the body part such that the slot opening is moved along the body part, whereby the fan beam limited by the radiation diaphragm of the radiation source is moved synchronously relative to the camera motion. The line detector camera can be horizontally or vertically arranged.

Abstract: A method and a apparatus for helical scan imaging in an X-ray CT, in which the initial set up operation can be achieved easily and accurately. In this X-ray CT apparatus, relative motion of a bed plate and an X-ray source is automatically controlled according to a desired imaging region specified by the operator such that the bed plate and the X-ray source are relatively moved through a distance covered by a scanning region appropriate for collecting the data required to reconstruct tomographic images for the desired imaging region. The scanning region includes the desired imaging region and supplementary interpolation data regions, located at the ends of the desired imaging region and utilized in carrying out interpolations for deriving data in the desired imaging region, and initial acceleration region accounting an initial acceleration of the bed plate, and a final deceleration region accounting a final deceleration of the bed plate.

Abstract: A high-energy X-ray inspection system comprises an X-ray source for generating high energy X rays for inspecting the contents of large objects. The source is contained within an enclosure having an integrally-formed precollimator device that limits the radiation emitted from the source to form a "fan-beam" of X rays. A novel rotating cylindrical collimator converts the fan-beam into a pencil-beam of X rays, which is further limited by a fixed-slit collimator. The high-energy pencil-beam penetrates the entire area of an object and is intercepted by a detector, which transforms the X rays into image data for presentation on a display screen.

Abstract: A digital X-ray imaging system having an X-ray generator, an X-ray generator controller for controlling the X-ray generator, an X-ray detecting unit for detecting an X-ray transmitted through a subject, the X-ray detecting unit having an X-ray grid for shielding a scattered X-ray, a signal processor for acquiring a signal from the X-ray detecting unit and processing the signal to obtain a digital X-ray image of the subject, and a display device for displaying an image of the subject obtained by the signal processor. The system is provided with a position changing unit for changing a relative position between the X-ray detecting unit and the subject, a position change controller for controlling the position changing unit, and an imaging-sequence controller for controlling the position change controller and the X-ray generator controller.

Abstract: An x-ray machine, such as a mammography machine, comprises a source of a narrow beam of radiation which scans across an object, e.g., a breast, to be imaged. A sensor for the narrow beam moves in the same direction as the narrow beam. The sensor generates an output signal which indicates the position of the beam relative to a specific location on the sensor. A control circuit receives the signal from the sensor and outputs a control signal to regulate the position of the beam relative to the sensor.

Abstract: A dual energy bone densitometer scans the whole body of a patient in successive passes with a narrow fan beam of x-rays and, between passes, moves the patient table along multiple axes and rotates the C-arm about a rotation axis spaced from the focal spot. The coordinated multi-axes motion of the table and C-arm helps in piecing together the x-ray data from different passes and helps reduce the footprint of the instrument.

Abstract: A scanning radiographic system having reduced scatter and improved tube loading employs a pre-patient slit to form the x-ray beam into a fan beam and a post-patient slot to eliminate scattered rays from the fan beam. A grid incorporated into the slot permits a further reduction of scatter sufficient to employ a wider slot without detrimental increase in scatter but with significant improvement in tube loading. The lamellae of the grid proceed diagonally across the width of the slot to reduce grid lines and are tipped to focus on the focal spot of the x-ray source.

Abstract: A displacement measuring system includes means for focusing x-rays into a narrow, intense beam which can be used to excite targets that fluoresce secondary x-rays. By precisely measuring the focused image position as the focused image is caused to overlap the fluorescing target, relevant changes in target position can be determined. The x-rays are focused using a novel Johansson ground and bent crystal which, along with the x-ray tube, is mounted on a common base for lineal scanning. This common base preferably comprises a linear translation table. By scanning the beam onto fluorescing targets, edge detection can be accomplished by monitoring subsequent x-ray fluorescing using an appropriate detector whose output is measured and recorded. In a preferred embodiment, the detector is formed integral with an enclosure for enclosing the x-ray tube and bent crystal on the linear translation table.

Abstract: A method and an apparatus for a helical scan imaging in an X-ray CT, in which the initial set up operation can be achieved easily and accurately. In this X-ray CT apparatus, a relative linear motion of the bed plate and the X-ray source is automatically controlled according to the desired imaging region specified by the operator such that the bed plate and the X-ray source is relatively linearly moved through a distance covered by a scanning region appropriate for collecting the data required in order to reconstruct the tomographic images for the desired imaging region. The scanning region includes the desired imaging region and the supplementary interpolation data regions, located at ends of the desired imaging region and utilized in carrying out interpolations for deriving data in the desired imaging region; an initial acceleration region for accounting an initial acceleration of the bed plate; and a final deceleration region for accounting a final deceleration of the bed plate.

Abstract: A computer tomography (CT) scanner may be retrofitted or redesigned to integrally include an analog X-ray detector which allows the CT scanner to be used to provide both high spatial resolution analog projection radiographs and high contrast resolution CT images. A cassette carrier having a curved slot defined therein is provided for placement on or in the moveable tabletop of the CT scanner. The patient is then placed upon or above the cassette carrier. A flexible cassette is then disposed within the curved cassette and assumes the radius of curvature defined by the slot. The radius of curvature is chosen such that the film cassette is focused on a collimated X-ray source within the CT scanner. The curved cassette includes or may be combined with a flexible X-ray grid placed proximate to adjacent the X-ray film. The film cassette includes a phosphor plate and photosensitive film plate held in immediate contact with phosphor plate by which the analog projection radiograph is recorded.

Abstract: A predetermined number of sectional planes are successively scanned, starting with a sectional plane in an initial position, by shifting a direction of X-ray emission from an X-ray emitting device. A reset operation is effected, after scanning the predetermined number of sectional planes, to switch the direction of X-ray emission to scan a sectional plane in the initial position. An examinee is moved synchronously with the reset operation to set a new sectional plane adjacent the predetermined number of sectional planes to the initial position. A predetermined number of sectional planes are successively scanned, starting with the new sectional plane in the initial position, by shifting the direction of X-ray emission from the X-ray emitting device. After scanning the predetermined number of sectional planes, a reset operation is effected and the examinee is moved to set a new sectional plane adjacent the predetermined number of sectional planes to the initial position.

Abstract: An x-ray diagnostics installation for peripheral angiography examinations includes a control unit having an arithmetic unit that, on the basis of subject-related data supplied thereto, effects a pre-setting of the electrical parameters of the installation required for every exposure, plus the step length and the number of steps of the relative adjustment of the exposure unit and the patient support relative to one another, as well as the required diaphragm setting. By virtue of the pre-setting, stress on the patient is reduced, and since the overall time per examination is also reduced, patient throughput can be increased.

Abstract: Method and apparatus for storing and moving an x-ray detector assembly in and out of the field of radiation produced by a radiation therapy simulator source while remaining affixed to the gantry of the simulator and retaining the functional attributes of a standard radiation therapy simulator cassette holder. When mounted to the simulator, the apparatus of the present invention has the ability to position an x-ray cassette in a fixed position relative to the radiation source, allow for the use of an image intensifier tube by being effectively radiolucent over the tube, and incorporating a mechanism which is capable of absorbing a degree of movement independent of the gantry while simultaneously activating a switch mechanism which can be used to stop gantry rotation, thereby preventing damage to the device or that which it contacts.

Abstract: A medical imaging apparatus includes a measurement unit with an x-ray source and a radiation detector rotatable around an examination subject to conduct a scan of the examination subject and thereby to obtain a data set, which is supplied to a computer. Within the computer, a shadowgraph of the examination subject is calculated in real time as the examination subject is displaced during the scan relative to the measurement unit. The data used to construct the shadowgraph are obtained at a selected projection angle, which is reached a number of times by the measurement unit during the scan. The shadowgraph is displayed in real time as well, to an extent correlated with the amount of relative displacement between the examination subject and the measurement unit. The shadowgraph can be calculated using a convolution equation, wherein the data are twice convolved, once in the longitudinal direction, i.e.

Abstract: In picking up a radiation image, and image is first picked up without adjusting the radiation dose of a radiation beam that scans an irradiation target to thereby acquire information of the dose of radiation transmitted through the irradiation target at the same time the image is picked up. Based on the information of the transmitted dose of radiation, the radiation dose to be controlled is determined, and image pickup is executed again to be superimposed on the initial pickup while controlling the radiation dose according to the determined control dose, whereby the radiation image data is obtained. Further, the image of the case where the radiation dose is not controlled is restored in signal processing of the obtained radiation image data and the data of the radiation control quantity.

Abstract: There is disclosed an assembly for slit radiography with image equalization, comprising a two-dimensional dosimeter for detecting the amount of X-rays transmitted through a body. During a scan different parts of the dosimeter detect the transmitted X-rays. Thereto a system of essentially parallel electrodes is present. The parallel electrodes extend in the direction of scanning and are connected to a control device for forming control signals for the adsorption device.

Abstract: A scanning radiographic densitometer constructs a broad area, two dimensional projection image from a combination of a set of smaller fan beam scans by tilting the axis of each such smaller scan to construct an effective larger fan beam to reduce artifacts caused by height dependant overlap of the multiple fan beams. The data is projected to a non-planar image surface to eliminate local area distortion such as may cause error in density measurements and to permit some overlap without height sensitive effects.

Abstract: A radiography apparatus with which x-ray shadowgraphs are produced has a detector array in the form of a line or strip, and an x-ray radiator which is moved in a direction perpendicular to the line direction of the detector array for scanning a measuring field from different directions. The detector array accordingly receives x-radiation proceeding through the measuring field from different directions. A screen or slotted diaphragm having diaphragm shafts directed onto the detector array is disposed between the x-ray radiator and the measuring field, and blanks out x-radiation which is not useful for generating the shadowgraph image.

Abstract: A slit radiography device scans a body under examination with a fan shaped X-ray beam. A number of absorption elements placed next to each other can be moved into the X-ray beam to a greater or lesser extent in order to influence the X-ray radiation incident on the body per sector of the X-ray beam.As seen in the longitudinal direction of the slit the absorption elements are designed such that a certain distance is present between them. As seen in the direction of the X-ray radiation the thickness of the material of the absorption elements is always the same, i.e. there are no gaps between the absorption elements that the X-ray radiation can shine through.

Abstract: X-ray examination of objects, which may be very large objects such as aircraft, boat hulls or lengthy pipelines, is accomplished with an x-ray source having a moving x-ray origin point that is scanned in a raster pattern. At least one x-ray detector having a very small x-ray sensitive area is disposed behind or within the object and provides an output signal indicative of internal characteristics of an adjacent region of the object. The source and detector undergo relative travel at least in a lateral direction during the examination to provide a sequence of different x-ray views that may include views of successive regions of the object, views from different angles and stereo views. X-ray images are produced at one or more monitor screens by sweeping a point of light in a raster pattern corresponding to that of the x-ray source while modulating the intensity of the point of light in accordance with the output signal of the detector.

Abstract: A radiation image recording apparatus comprises a source of radiation and a radiation image recording medium located facing the radiation source. A first slit plate is composed of a radiation absorber and at least two parallel slits, through which the radiation passes. The first slit plate is located between the radiation source and an object, which object is placed between the radiation source and the radiation image recording medium. A second slit plate is composed of a radiation absorber and at least two parallel slits, through which the radiation passes. The second slit plate is located between the object and the radiation image recording medium such that the slits of the second slit plate may be parallel to the slits of the first slit plate.