Abstract: The invention relates to a scatter grid drive for oscillating a scatter grid back and forth during an exposure. The reversal point, at which the direction of movement of grid is reversed, is passed so quickly that there is little risk of imaging the grid in the radiograph.

Abstract: On-line apparatus for analyzing the formation of a moving web of paper, using a source of light directing a beam through the paper and a photodetector receiving the light which has passed through the paper, has a circuit preferably including a tunable band pass filter and demodulator producing a D.C. output reflecting size and distribution of flocs. The output gives similar results to those obtained by visual judgement of formation.

Abstract: A magnetic field gradiometer includes a geometric arrangement of fiber op sensors through which light from a single frequency laser is transmitted. Having a pair of single-mode optical fibers, each of which are coupled to a magnetostrictive element, each sensor is formed in the manner of a Mach-Zehnder interferometer which is oriented to detect the spatial variation in a particular orthogonal component of the magnetic field by phase comparison of the light transmitted through its respective pair of fibers.

Abstract: The invention relates to a soft tissue filter arrangement in X-ray imaging of a patient's skull by means of a chefalostat, wherein a patient (P) is by means of ear plugs (5) or the like supports preferably fixed relative to imaging coordinates as well as by means of a nasion and/or forehead support (6) set in a determined position and location between an X-ray source (1) and a film (4) or the like imaging medium and wherein the X-ray source is provided with diaphragm (2) for directing X-rays to the patient and restricting them to a proper sized beam (3) for imaging. The arrangement comprises preferably V-shaped filter means (7) whose position relative to the soft tissues of a patient's face in a cross-sectional plane perpendicular to the X-ray beam is adapted to be set on the basis of a distance (D) between said ear plugs (5) or the like supports and said nasion and/or forehead support (6) or on the basis of a patient's skull dimension correlating sufficiently well therewith.

Abstract: The bearing in an X-ray tube comprising a liquid metal lubricated helical-groove bearing is provided with a push-pull bearing at one or both end faces of a bearing member. Consequently, the bearing member need not be further secured so that, notably in the case of suitable cooling of the anode disc and the bearing, extremely precise positioning of the radiation object point in the tube can be achieved.

Abstract: A high voltage supply circuit for an x-ray tube includes a high voltage transformer having a primary side driven by voltage pulses generated by a drive circuit. The drive circuit includes sub-circuits for controlling the pulse repetition frequency, which is selected as equal to a parallel resonant frequency of a high voltage generator connected to the secondary side of the transformer, for the purpose of saving energy. The drive circuit also includes a sub-circuit for controlling the pulse duration, with the filament voltage in the x-ray tube being regulated by this pulse duration.

Abstract: An airflow detection system comprising a light source for generating an optical signal that is propagated in an optical guide having a plurality of sensors responsive to the presence of airflow, each of which modulates the intensity of the optical signal at a frequency characteristic of that sensor such that a detection apparatus can receive the optical signal and identify activated sensors using frequency domain multiplexing techniques.

Abstract: A system for improving the performance of video cameras used in Digital Subtraction Angiography wherein the cameras have tubes comprising targets with elements in said target that correspond to pixels of an image. The method basically comprises the step of defocusing the electron beam especially during the scrubbing operation so that the electron beam impinges on more than one element at a time.

Abstract: In an X-ray analysis apparatus, a moving mechanism is provided by a main guide member along which a main slide device can be displaced. Rotatably connected with the main slide device is a detector guide member along which a detection slide device is displaced. The main slide device, as well as the detection slide device, and an axis of rotation relative to an end of the main guide member are connected to a common central axis by respective arms which can be mutually rotated with them. The main slide device and the detection slide device can each be equipped with a drive motor where the motor for the main slide device is preferably driven first, and the motor for the detector slide device is driven by signals derived from displacing the main slide device.

Abstract: The invention relates to an X-ray examination apparatus in which the X-ray source and the X-ray detector are secured to a C-shaped or U-shaped support. This support comprises two arms which are pivotable about parallel axes and which are coupled to one another in such a way that opposite pivotal movements through equal angles are obtained. The C-shape or the U-shape of the support is then changed, so that the support can be rotated without the risk of a collision with the table top carrying the patient.

Abstract: The invention relates to a dental instrument for optimal positioning of an X-ray film support in the X-raying of teeth, especially front teeth, or adjacent tissues. The instrument comprises a bridge having at its one end which is located in the patient's oral cavity inside the subject to be X-rayed a holder keeping the film positioned perpendicularly to the longitudinal axis of the bridge and means receiving an alignment rod which is parallel to the longitudinal axis of the bridge and which projects outside the oral cavity whereby the optical axis of the X-ray camera can be positioned relatively the rod and hence relatively the film. The instrument is improved by means of a transverse support arm connected to the bridge and adapted to be held pressed between the teeth in the upper and lower jaws permitting rotation of the film holder around the geometric longitudinal axis of the support arm.

Abstract: In a digital intravenous subtraction fluorographic system, X-ray subtraction images obtained by performing a subtraction between the precontrast images and the post-contrast images are processed by comparing, for each pixel, the value of the pixel image data in the difference image with a predetermined threshold intensity value, and recognizing the time until the value of the pixel image data reaches the threshold intensity value. The resulting time data so determined in the processor is used for displaying the distribution of contrast medium in the vessel in relation to the time periods it takes for each pixel to attain the predetermined threshold intensity. In effect, the time data for each pixel is itself converted to an intensity signal dependent on the amount of time it takes for each pixel to cross the predetermined threshold intensity, and it is the time period derived intensity signal which is displayed.

Abstract: A scanning beam computed tomography scanner is disclosed herein and includes means defining a vacuum chamber, means for producing an electron beam at one location in the chamber and for directing it to a second location therein, a target of the type which produces X-rays as a result of the impingement thereon by the electron beam, and means for focusing the beam onto the target in the form of a beam spot and for scanning the beam spot across the target along a particular scan path in order to produce X-rays. The specific scanner disclosed also includes an arrangement for monitoring the profile, position and orientation of the beam spot at a plurality of different points along the scan path.

Abstract: A diagnostic X-ray apparatus emitting pulsed X-ray radiation includes a processor for performing digital X-ray subtraction of a previous mask image from current images. The apparatus includes circuitry for digitization of the video signals from an image intensifier-TV chain, digital subtraction to obtain digital difference signals, and subsequent reconversion of the resultant digital difference video signals to analog signals. Pulsed X-ray exposures are performed during the blanking periods of the TV camera following which the television fields immediately following the pulsed X-ray exposure are scanned and read out, and are supplied to the processor for performing the digital X-ray subtraction.

Abstract: An X-ray simulator has an X-ray source and collimator connected to the end of a cantilevered horizontal arm mounted on a gantry that rotates about a horizontal axis and extends along a patient supporting table. The horizontal arm has an asymmetrical cross section that causes the arm and therefore the X-ray source and collimator to deflect by differing amounts as the gantry rotates. To compensate for the varying displacement of the X-ray target point and to adjust the position of the target point along the rotation axis of the gantry, the collimator is pivoted in one direction or the other in accordance with the amount of rotation of the gantry axis.

Abstract: A machine for radiologically examining a patient employs a radiation source and a monochromator. The monochromator can reflect radiation from the source toward the patient. This monochromator is angularly positioned to narrow the bandwidth of the reflected radiation around a predetermined center wavelength. A discharge detector is positioned alongside the patient opposite the monochromator for producing a discharge in an electric field in response to receipt of the reflected radiation. Also included is a counting apparatus for measuring the extent of discharge in the discharge detector.

Abstract: An X-ray CT diagnostic apparatus includes an unit for producing a scannogram of an object under examination, a unit for designating a plurality of slice positions on the scannogram by utilizing a line/marker generator, a unit for designating an interest region of the designated slice position in the scannogram, which is to be enlarged, by defining a center of the interest region by means of the line/marker generator, and a unit for enlarging and reconstructing the interest region of the designated slice position in such a manner that a center of the enlarged and reconstructed interest region is concident with the center of the interest region which has been designated in the scannogram.

Abstract: For angiographic X-ray examinations with an image intensifier-television installation, three image memories are connected to a control generator which in respective clock pulse intervals cyclically places a respective one of the image memories in the write state for the purpose of storage of a current video signal which is averaged over several images. A subtraction device for the subtraction of image data occurring at various times receives the current video signal and the output signal of the one image memory in the write state. Connected to the subtraction device is a maximum detector which recognizes the maximum of the contrast medium flow and in response thereto actuates the control generator to cause the image memory which was last in the write state, and the image memory with the chronologically oldest video signal to be switched to the read state and to produce a difference signal for display on a video display based on the readout from such image memories.

Abstract: A localizer system is described which enables determination of the coordinates of a target located inside the human body and visualized on a tomographic scan image for essentially any arbitrary scan plane through the body. It involves a means of fixing a frame in a known relationship to the body and placing the localizer system in a fixed position relative to the frame. There is an axial axis defined for the localizer, and there are both parallel and transverse (perpendicular) rod elements as well as diagonal rod elements on the localizer. These appear as spot images on the scan plane image and are sufficient in number and location to enable accurate calculation of a target image on the scan and determination of the target coordinates in space relative to the localizer. This applies to plane scan cuts which are substantially parallel or perpendicular to the localizer axis.

Abstract: The present invention is directed, in an X-ray lithographic system characterized by a plurality of work stations, a cartridge, apparatus for mounting a wafer and a mask on the cartridge, a system for moving the cartridge between stations, apparatus in each of the stations for moving the cartridge to a kinematic mount, said kinematic mounts in all of said stations being substantially identical, to the improvement comprising: a bistable foot operable in a first linear elevational mode and in a second angular compliance mode.