Abstract: A method of adjusting the alignment of a sighting device (5) and a member (4) coupled therewith, said member being pivotable in at least one plane about a first pivot axis (3), and at least part (7) of said sighting device (5) being pivotable about a second pivot axis (6). On the pivotable member an apparatus is mounted which provides a parallel beam of radiation shining directly or indirectly on to the pivotable part (7) of the sighting device (5), and being productive of a point image at the viewing end of the sighting device. The pivotable member is moved into a plurality of different angular positions relative to the first pivot axis (3), and, if during these movements the point image is moved beyond a pre-determined tolerance range, the coupling (8) between the pivotable member and the sighting device is adjusted.

Abstract: A dosimeter is described that does not show differences in sensitivity over its sensitive area when the ambient pressure changes. To that purpose the measuring chamber and a pressure compensation element together form a single gas tight chamber having at least partially of slack material, wherein the pressure inside the measuring chamber is essentially equal to ambient pressure such that no mechanical distortion of the measuring chamber over its sensitive area takes place.

Abstract: Anti-veiling-glare glass input window for an optical device. The window has throughout a shallow surface layer over its peripheral surfaces radiation absorbent free-metal-induced color centers. A method for preparation of such a window, which is particularly suited to be used as an input window for an image intensifier, involves preshaping the window from a clear glass and forming color centers in a shallow surface layer over at least the peripheral surfaces of the window. If the clear glass contains reduceable metal oxides the color centers are formed by subjecting at least the peripheral surfaces of the clear glass to a reducing atmosphere at a temperature high enough to cause the reducing atmospheres reducing component to diffuse into a shallow surface layer of the window and to reduce the metal oxides to free metal atoms.

Abstract: There is disclosed an assembly for slit radiography with image equalization, comprising an X-ray source which can scan a body for examination via a slit of a slit diaphragm with a flat, fan-shaped X-ray beam over a scanning path in a direction transverse to the lengthwise direction of the slit for forming an X-ray shadowgraph on an X-ray detector; an absorption device which under the control of control signals can influence the fan-shaped X-ray beam per sector thereof, in order to permit control of the X-ray radiation falling in each sector on the body to be examined; and detection assembly which is designed to detect the quantity of X-ray radiation transmitted by the body instantaneously per sector during a scanning movement of the X-ray beam and to convert it into corresponding signals.

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: An ultrasound transducer generates a received signal in response to a reflected ultrasound signal. Polarity and phase information of the reflected ultrasound signal can be obtained by time-selectively amplifying the received signal with a specific gain function. The specific gain function is derived from the received signal itself and is independent of the polarity of the received signal.

Abstract: An apparatus for slit radiography is provided with a slot diaphragm to form a fan-shaped X-ray beam with which a body can be scanned. Controllable attenuating elements interact with the slit diaphragm to influence sectors of the fan-shaped X-ray beam. They are controlled by signals representing the instantaneous transmission of the body in the corresponding sectors. The hardness of the fan-shaped X-ray beam is varied periodically in a predetermined manner. Synchronously with the periodic variation of the hardness of the X-ray beam the attenuating elements are oscillated. The oscillation of the attenuating elements is superimposed at each instant on the instantaneous position determined by the signals representing the instantaneous body transmission. The amplitude of the oscillation is less than the height of the slit of the slit diaphragm. The influence on the X-ray beam is most at the instants at which the hardness is greatest.

Abstract: A collimating mark device is provided with an infrared collimating mark intended to be observed through a sight. The infrared collimating mark is designed such that at least two V-shaped intensity distributions are positioned in a way that their respective apexes are facing one another. Despite a relatively blurred image after conversion into a visible collimating mark, the blurred visible collimating mark can be brought in a reproducible and reliable manner into coincidence with a fixed alignment mark.

Abstract: There are disclosed methods for making radiographs using slit-scanning radiographic techniques wherein a measuring exposure is effected at low radiation intensity and thereafter radiation intensity is set at a value suitable for effecting and taking the actual exposure and further including a modulation of radiation intensity during actual exposure.

Abstract: In a method for slit radiography a fan-shaped X-ray beam scans a body to form an X-ray shadow image. The fan-shaped beam is formed by a number of sectors situated next to each other. For each sector the transmitted X-ray radiation is controlled instantaneously during a scan by means of controllable beam sector modulators. The X-ray radiation is cyclically modulated in a predetermined manner for all the sectors taken together. The controllable beam sector modulators are individually controlled to select cyclically and in synchronism with the predetermined cyclic modulation a part of the X-ray radiation for each sector.

Abstract: An image pickup device comprises a matrix of rows and columns of image pickup elements. Image information is transferred in the column direction in the time-delay-and-integration mode. Each column comprises at least two regions containing image pickup elements, whereby spectrally different images can be picked up during a single scan.

Abstract: An image pickup device comprises a matrix of rows and columns of image pickup elements. Image information is transferred in the column direction in the time-delay-and-integration mode. Two shift registers are associated with each column of image pickup elements. During a first period information from the image pickup elements of each column is transferred to a first one of each two shift registers associated with each column and during a second period information is transferred to the second one of each two shift registers associated with each column.Such an image pickup device can be used in radiography as a means for detecting x-ray radiation transmitted by a body under examination. In order to obtain a dual energy image a first or a second spectral center point is periodically imparted to the x-ray radiation synchronously with the first and second periods.

Abstract: In a method for slit radiography a fan-shaped X-ray beam scans a body to form an X-ray shadow image. The fan-shaped beam is formed by a number of sectors situated next to each other. For each sector the transmitted X-ray radiation is controlled instantaneously during a scan by means of controllable beam sector modulators. The X-ray radiation is cyclically modulated in a predetermined manner for all the sectors taken together. The controllable beam sector modulators are individually controlled to select cyclically and in synchronism with the predetermined cyclic modulation a part of the X-ray radiation for each sector.

Abstract: A dosimeter for ionizing radiation is of oblong shape. It comprises a gas-filled measuring chamber surrounded by a casing. THe casing is formed of two oblong frames of insulating material that are substantially similar in shape. The two frames are mounted on each other in a gas-tight manner. The anode wires are situated in the plane of separation between the frames and are secured by the frames in contact with each other. At least one of the frames is provided with a cathode over its whole length and parallel to the plane in which the anode wires are situated. Along the edge of the cathode extends a guard electrode which surrounds the cathode with a certain gap. The dosimeter is made of materials that are transparant to the ionizing radiation. It can be used particularly in slit radiography equipment in which the slitwidth can be controlled locally and independently along the length of the slit.

Abstract: A piezo-electric attenuation tongue system for slit radiography equipment comprises a number of tongues placed next to each other. The tongue system is manufactured by slitting a plate of piezoelectric material from one of the edges but leaving unslit a strip of the plate along the opposite edge.

Abstract: The housing of an elongated proximity-focus image intensifier comprises at least two elongated parts. The parts have in cross-section such dimensions and such a configuration that the housing is self-supporting. An exemplary embodiment of such a housing which is essentially rectangular in cross-section has a front wall, a rear wall and two side walls, all having an essentially rectangular cross-section. In the case of at least two pairs of adjacent walls the edge in the longitudinal direction of the surface, facing the interior of the housing, of a first of the pair of walls is provided with profiling in the form of a recessed section in which the longitudinal edge of the adjacent tube wall is received.

Abstract: An X-ray detector tube comprising an essentially rectangular, elongate housing (1) having a forward wall, a rear wall and sidewalls, which tube has an elongate proximity focus image intensifier mounted therein and which housing has a vacuum established therein, in which the rear wall (5) of the tube exhibits a considerably higher resistance to deformation than the sidewalls.

Abstract: An apparatus and method for slit radiography, in which a body to be irradiated is scanned at least twice by means of a planar, fan X-ray beam emitted from an X-ray source (1) via a slit diaphragm (2), the hardness of which beam increases with each next scanning motion, in which an X-ray detector (6) mounted behind the body collects the radiation passed, sections of detection means (10), which sections are juxtaposed in the longitudinal direction of the X-ray detector, produce electrical signals depending upon the radiation collected by the respective X-ray detector sections, which signals are sampled during each scanning motion and are stored in a memory, and the diaphragm (2) includes controllable elements juxtaposed in the longitudinal direction of the slit in a plurality corresponding to that of the sections of the detection means, which controllable elements are each operative to locally block the slit diaphragm during a next scanning motion if a stored signal produced by the corresponding section of the

Abstract: A system comprising an X-ray source (1), an elongate detector tube (3) including at least one cathode (5) extending in the longitudinal direction of the tube and at least one anode (6) located opposite to the cathode, a slit diaphragm (2), and a filter (4) mounted in the path between the X-ray source (1) and the detector tube (3). The filter (4) blocks relatively low energy X-radiation in a portion of the beam emitted by the source (1). The cathode (5) is provided with an X-ray detection layer consisting of two strips (8',8") extending in the longitudinal direction of the tube (3). One strip (8") receives the radiation passed by the filter (4) and the other strip (8') receives the unfiltered radiation. The one strip (8") is of considerably greater thickness than the other strip (8').

Abstract: There is disclosed a method for forming a radiogram of an object comprising the steps of energizing an X-ray source at a low level of radiation intensity wherein the X-ray source includes a slit diaphragm, pivoting the X-ray source during a first scanning of the object, moving an elongated X-ray detector in respect to the pivoting of the X-ray source to generate an output signal of intensity of the object during the first scanning thereof, measuring the output signal during at least a portion of said first scanning, energizing the X-ray source to a higher level of radiation intensity as determined by the output signal from the X-ray detector during the first scanning, pivoting the X-ray source during a second scanning of the object, moving the X-ray detector during the second scanning to generate a second output of radiation intensity and forming a radiogram from the second output signals.