Abstract: An anode and a cathode are in an evacuated metal envelope comprising a radiation exit window and which carry a positive and a negative high voltage, respectively, with respect thereto during operation. The cathode, at its area which neighbors the radiation exit window, has a ridge segment which extends in the axial direction partially about the cathode filament. The segment shields the radiation exit window from the electrons emitted by the cathode to reduce heating of the window by the electrons.

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: A method and apparatus for altering the focal length of a focusing element o one of a plurality of pre-determined focal lengths by changing heat transfer within selected portions of the element by controlled quantities. Control over heat transfer is accomplished by manipulating one or more of a number of variables, including: the amount of heat or cold applied to surfaces; type of fluids pumped through channels for heating and cooling; temperatures, directions of flow and rates of flow of fluids; and placement of channels.

Abstract: Apparatus for directing and focusing X-rays by the new method of confinement is disclosed. A capillary having an inlet end and an outlet end with a generally tubular or rectangular inner wall surface defines a longitudinal central opening. The central opening is tapered inwardly from the inlet end to the outlet end. X-rays are directed into the inlet end at angles less than the critical glancing angle for the inner wall surface to direct X-rays through the capillary to a focus point near the capillary outlet end.

Abstract: A method and apparatus for improving imaging in an X-ray mammography machine having a controllable X-ray source incorporates apparatus for directing the X-ray beam in a preselected configuration onto at least a portion of a target area. The creation intensity of the beam is detected in each of a plurality of substantially equal segments of the target area and a first segment of lowest radiation intensity is identified. The X-ray source is adjusted to establish a predetermined radiation intensity in the identified first segment. Second segments are then identified each having a radiation intensity greater than a predetermined percentage of the radiation intensity in the identified first segment. The radiation intensity directed toward the identified second segments is then automatically attenuated by a control system responsive to the radiation intensity detected in the second segments.

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: Irradiation equipment comprising a beam duct disposed along the synchrotron radiation beam, and a multistage axial flow turbine installed in the beam duct. The multistage axial flow turbine comprises a plurality of stators and rotors arranged alternately in an axial direction. Each stator has vanes and a beam transmission hole formed through the vane region. Each rotor has vanes and gaps between adjacent vanes. A plurality of beam transmission holes are aligned in a direction of the synchrotron radiation beam, and a plurality of gaps of the rotors are intermittently aligned in the direction of the synchrotron radiation beam, whereby the synchrotron radiation beam can intermittently penetrate through the multistage axial flow turbine through the beam transmission holes and gaps with rotation of the rotor.

Abstract: A method of treating a substrate having first and second sides with corresponding oppositely facing first and second surfaces, to produce curvature in the first surface. The method includes the steps of removing material, according to a predetermined pattern, from the second side of the substrate, and applying a stress-producing film of material to at least one surface of the substrate to thereby cause the substrate to bend to produce the desired curvature in the first surface.

Abstract: An X-ray exposure apparatus comprises an X-ray source, a reflecting mirror for deflecting an X-ray beam radiated from the X-ray source to an object, and mechanisms for rotating the reflecting mirror about an axis of rotation apart from a reflecting surface of the reflecting mirror. The reflecting mirror has such a shape that the angle of incidence remains constant relative to the X-ray beam at given angles of rotation.

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

Abstract: A radiographic machine in which the exposure is equalized as between different areas of the image plane so as to enhance high spatial frequency features of the image and suppress low spatial frequency features and achieve other benefits as well. A fan beam which is wide enough to encompass the object being imaged is swept across the object and segments of that beam are individually pulse width modulated at each of a number of sampling intervals during the sweep by monastable or bistable shutter pins which either completely block or completely uncover the sectors which they control. An alternate embodiment adds beam width moulation as well, by making the shutter pins either completely block their sectors of uncover them only to the degree necessary for beam width modulation.

Abstract: An apparatus and method for finishing an X-ray mirror, having a substantially cylindrical mirror body and a reflecting mirror surface on the inner surface of the mirror body, includes a support post supporting the mirror body, and a male member which is inserted into an unfinished mirror body. The male member includes a chamber therein, an outer circumferential surface shaped in correspondence with the reflecting mirror surface, and a number of fine holes open to the outer circumferential surface. The male member is supported by a support section so that the outer circumferential surface faces the reflecting mirror surface with a required gap. An abrasive solution containing free abrasive grains is ejected toward the reflecting mirror surface from the outer circumferential surface of the male member through the fine holes, thereby polishing the reflecting mirror surface.

Abstract: A collision preventive device for medical equipment (such as readiotherapy equipment) having moving parts to which accessaries are disengageably attached includes a contact detection circuit in which the normally closed contact detector switches disposed on the moving part and on the accessary are all coupled in series, so that an occurrence of contact of the moving part or of the accessary attached thereto can be detected by a relay coupled across a current source in series with the contact detector switches.

Abstract: A multilayer x-ray reflector or reflectors are used with a source of radiation for narrow bandwidth or dual energy radiographic imaging applications. In one aspect, a unique multilayer design permits two distinct x-ray energies of narrow bandwith to be reflected at the same incident angle for use in dual energy applications. In another aspect, several multilayer reflectors are employed in a slit scanning system. In yet another aspect, an elongated radiation source and a multilayer x-ray reflecting structure are combined to provide an x-ray or gamma ray source.

Abstract: There is disclosed a dosimeter to be used in connection with slit radiography and comprised of a gas filled chamber with one side wall provided with a plurality of X-ray transparent strip-like electrodes extending substantially transversely to a longitudinal direction of the oblong-shaped casing and another side wall provided with wire electrodes extending parallel to such longitudinal direction of the oblong-shaped casing wherein each of the strip-like electrodes generates a signal representative of intensity of ionizing radiation and wherein the strip-like electrodes are divided into a number of groups, signals from the strip-like electrodes belonging to each group are combined to provide a control signal for a respective attenuation element.

Abstract: A radiographic machine in which the exposure is equalized as between different areas of the image plane so as to enhance high spatial frequency features of the image and suppress low spatial frequency features and achieve other benefits as well. A fan beam which is wide enough to encompass the object being imaged is swept across the object and segments of that beam are individually pulse width modulated at each of a number of sampling intervals during the sweep by monostable or bistable shutter pins which either completely block or completely uncover the sectors which they control. An alternate embodiment adds beam width modulation as well, by making the shutter pins either completely block their sectors of uncover them only to the degree necessary for beam width modulation.

Abstract: An intense, relatively inexpensive X-ray source (as compared to a synchrotron emitter) for technological, scientific, and spectroscopic purposes. A conical radiation pattern produced by a single foil or stack of foils is focused by optics to increase the intensity of the radiation at a distance from the conical radiator.

Abstract: A method of making a grid for x-ray radiography including the steps of forming grid patterns of x-ray opaque material on a plurality of sheets of x-ray transparent material, aligning the sheets in a stack, and bonding the sheets together to form a lightweight stacked grid.

Abstract: A lithography system is disclosed which is capable of doubling the spatial frequency resolution associated with conventional systems. A spatial filter, positioned to intercept the Fraunhofer diffraction pattern of the mask being exposed, is configured to prevent certain orders of the diffraction pattern (in most causes the O-order and .+-.2nd, 3rd, . . . orders) from reaching the wafer's surface. The remaining orders reaching the wafer surface (in most cases the .+-. first-order beams) will produce a cos-type interference pattern with a period half of that if the mask grating were imaged without spatial filtering. Therefore, for a system with a given magnification factor m, a mask grating with a period p will be exposed on the wafer surface as a grating with a period of p'=pm/2. Advantageously, the spatial filtering technique of the present invention allows for a variety of different structures (conventional gratings, chirped and phase-shifted gratings, grids, Fresnel zone plates, etc.

Abstract: A soft X-ray lithographic system for making a reduced copy of a pattern is described. The system contains a source of soft X-rays, a spherical concave reflector which convergently projects the soft X-rays from the emitting means through a pattern to be copied and a Fresnel zone plate which focuses and reduces the beam of soft X-rays convergently projected through the pattern.

Abstract: A tomographic inspection system wherein the electron beam of a microfocus X-ray tube is deflected in a circular scan pattern onto the tube anode in synchronization with a rotating detector that converts the X-ray shadowgraph into an optical image and derotates the image so as to be viewed and integrated in a stationary video camera. A computer system controls an automated positioning system that supports the item under inspection and moves successive areas of interest into view. In order to maintain high image quality, a computer system also controls the synchronization of the electron beam deflection and rotating optical system, making adjustments for inaccuracies of the mechanics of the system. The computer system can also operate under program control to automatically analyze data, measure characteristics of the item under inspection and make decisions regarding the acceptability of the item's quality.

Abstract: An X-ray mirror having its layer structure in the sequence of: a substrate having the surface roughness (R.sub.max) of 1,000 .ANG. or below; an intermediate layer of high molecular weight material formed on this substrate and having a surface roughness (R.sub.max) of 100 .ANG. or below; and a thin film formed on this intermediate layer, the X-ray mirror being produced by the process steps of: providing a substrate having a surface roughness (R.sub.max) of 1,000 .ANG. or below; forming on this substrate an intermediate layer of a high molecular weight material by spin-coating with a surface roughness (R.sub.max) of 100 .ANG. or below; and finally forming a thin film on this intermediate layer.

Abstract: A thin, flexible, hollow fiber capable of transmitting ionizing radiation. Ionizing radiation enters the fiber through entrance pupil (10) and travels through the hollow interior of fiber body (20) by reflecting and scattering off the inner wall of the fiber, frequently at grazing incidence angles. Fiber body (20) is covered at one end by thin film cap (30) which is thin enough to be at least semitransparent to ionizing radiation, but which is also strong enough to allow air to be withdrawn from fiber body (20) at the opposite uncapped end. Small obstructions (32) at the exit end of the fiber can be used to spread the beam of ionizing radiation to a desirable width. A flexible fiber capable of transmitting ionizing radiation has important applications in medicine for the radiation therapy of tumors. Applications also exist in communications and other fields.

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

Abstract: An x-ray beamsplitter which splits an x-ray beam into two coherent parts by reflecting and transmitting some fraction of an incident beam has applications for x-ray interferometry, x-ray holography, x-ray beam manipulation, and x-ray laser cavity output couplers. The beamsplitter is formed of a wavelength selective multilayer thin film supported by a very thin x-ray transparent membrane. The beamsplitter resonantly transmits and reflects x-rays through thin film interference effects. A thin film is formed of 5-50 pairs of alternate Mo/Si layers with a period of 20-250 A. The support membrane is 10-200 nm of silicon nitride or boron nitride. The multilayer/support membrane structure is formed across a window in a substrate by first forming the structure on a solid substrate and then forming a window in the substrate to leave a free-standing structure over the window.

Abstract: A dosimeter for ionizing radiation is of oblong shape. It comprises a gas-filled measuring chamber surrounded by a casing. Two opposite side walls are manufactured of material transparent to the ionizing radiation. One of the transparent side walls is provided with a transparent plate-like electrode. The other transparent side wall is provided with a number of strip-like electrodes extending transversely to the longitudinal direction of the measuring chamber. A guard electrode surrounds the plate-like electrode. The dosimeter being transparent to X-rays 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: An x-ray detector system has a detector element disposed at the end of a channel formed by spaced collimator plates. The thickness of each collimator plate projected onto the detector element increases along the length of the collimator plates in the direction of radiation propagation through the channel. The projection (and thus the thickness) has a greatest value at a detector-proximate end of the plate. The edge regions of the detector element are thus shielded from x-radiation by the extended width collimator plates. The length of the absorption paths in the detector element thus are substantially the same, even given a detector element which is slightly obliquely disposed. Thus the shape of the portion of the detector surface effective for detecting radiation is substantially independent of slight changes in the focus position.

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: An alloy filter in the form of a plate made from a homogeneous alloy comprising 85-95 wt. % cadmium, 5-15 wt. % copper and up to 3 wt. % of incidental impurities is interposed between a collimator and sodium iodide crystal of a gamma camera. The alloy filter improves image resolution by allowing the passage only of emmissions which impinge substantially perpendicularly on the collimator, while filtering out others which impinge obliquely.

Abstract: A shielding apparatus for use in conjunction with an X-ray generator is disclosed. The apparatus comprises a shielding cone extending from the X-ray generator toward the object to be X-rayed, said cone comprising an upper cone portion detachably connected to the X-ray generator, a lower cone portion forming the base of the cone and a plurality of panels detachably connected to and extending between the upper and lower cone support portions. Additional shielding components are provided about the X-ray generator and secured to the shielded cone to further reduce the emission of stray X-rays.

Abstract: An X-ray imaging system has an X-ray source, an X-ray image detection section, an X-ray mask member, a drive unit, a memory, a calculating section, and an image output unit. An X-ray image is detected by the X-ray image detection section. The X-ray mask member has X-ray shielding regions, distributed in a predetermined pattern, which locally shield the X-ray. The mask member is driven by the drive unit so that it is inserted in or removed from an X-ray radiation field between the X-ray image detection section and the X-ray source, and is sequentially displaced to predetermined positions in the radiation field. The calculating section calculates scattered X-ray intensity distribution data based on a plurality of transmission X-ray data obtained by irradiating an object with X-rays with the mask member located at different positions in the radiation field, and transmission X-ray data obtained by irradiating the object with X-rays with the mask member located outside this field.

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

Abstract: A radiation field-shielding device is mounted on a collimator (4) in an radiotherapy apparatus. The collimator (4) is rotatable in a per se known manner about its axis and in its entirety about the horizontal axis of rotation of the radiotherapy apparatus for irradiating a patient lying on a treatment table. The device (5) comprises a housing (25) removably mounted on the collimator (4), and a holder (10) with radiation shield means (11) spaced from the collimator (4). The holder (10) is pivotable about a shaft (26) away from its position in front of the collimator (4) to a position at the side of the collimator (4), in which position the holder (10) is rotatable about a second shaft oriented towards the center of the holder (10) and extending at right angles to the first shaft (26). In this manner, there is obtained, by two simple operations of rotation, a mirror inversion of the shield means (11) without necessitating dismounting or shifting thereof.

Abstract: An X-ray exposure system including a plurality of X-ray exposure apparatuses each for duplicating a mask pattern on a semiconductor wafer by irradiating an X-ray mask and the semiconductor wafer with synchrotron radiation is disclosed in which a synchrotron radiation path branching device including a reflecting mirror is disposed between a synchrotron ring and the X-ray exposure apparatuses, and the propagation direction of the synchrotron radiation emitted from the synchrotron ring is changed by the reflecting mirror so that the synchrotron radiation from the ring can be introduced into each of the X-ray exposure apparatuses.

Abstract: A radioscopic image former comprises a slit between an X-ray source and a subject to produce an X-ray fan beam to scan the subject. The transmission of the slit is adjusted locally during the scanning depending on local absorptions in the subject. The X-ray fan beam is cyclically modulated. The local modulation frequency depends on the coordinate in the longitudinal direction of the slit. The slit comprises a number of tongues each tongue being excited at or near its resonant frequency. Each tongue has its own frequency or phase and acts as a frequency-selective element.

Abstract: An X-ray source includes a thin film X-ray target for generating and focusing X-rays in response to the application of electron beams, and a capillary tubular element for allowing the X-rays to pass. The capillary tubular element has such a diameter the beams of the X-rays impinging on the inner surfaces of the capillary tubular element are totally reflected. Additionally, a thin film is provided for adsorbing the electron beams, but allowing the X-rays to penetrate.

Abstract: Method and modifying body for influencing the effect of X-ray or gamma radiation on a target (7) sensitive to radiation, in particular for selective modification of a radiograph of an object (10). According to the invention a modifying body comprising at least two layer groups (31, . . . 3n) is arranged in front of the target, wherein each layer group (e.g., 32) emits a secondary radiation under the influence of the X-ray or gamma radiation or the secondary radiation of the previous layer group (e.g., 31), respectively, the energy of which is lying above the absorption energy level defined by the electron shell K of an element being present in the following layer group (e.g., 33) or in the target arranged behind the last layer group (3n), respectively.

Abstract: A scanning system for use in radiology incorporates two disks bearing identically patterned, radial arrays of apertures and corresponding X-ray detection materials, respectively. The disks are axially aligned and synchronously rotated on opposite sides of the radiological target. X-rays emitted adjacent to the first disk are strobed by the apertures and detected by photodiode arrays on the second disk after passing through said target. The detection array is scanned to produce the X-ray information for digital processing and imaging. The foregoing apparatus may be portable and mounted for retrofitting relative to existing X-ray installations.

Abstract: An apparatus for slit radiography which comprises an X-ray source and a slit diaphragm through which a body to be examined can be scanned by a planar X-ray fan beam. The slit diaphragm is operatively associated with a plurality of juxtaposed tongue-shaped attenuation elements, which elements are arranged for having their free ends swung to a greater or lesser extent into the X-ray beam so as to effect a local attenuation of the beam. The tongue-shaped attenuation elements form at least one flared configuration as seen from the X-ray source.

Abstract: A scatter radiation compensation method for use in a medical diagnosis x-ray imaging system employs the use of an attenuating material placed in an x-ray beam to attenuate a portion of the beam such that the in-line component of the beam is reduced in the attenuated area. In one embodiment, an additional image is then taken utilizing an attenuator through out the full area of the beam to provide an image indicative of in-line components of the x-ray beam. The difference in image intensity between the two images is then computed to determine the scatter component of intensity and that intensity is thereafter substracted from the overall intensity obtained in a medical diagnostic image to obtain an image with the scattering effects removed. In one embodiment, the attenuating objects are plural spaced objects located at predetermined positions in the image.

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

Abstract: A collimator for a radiation diagnostics apparatus has two parallel spaced carriers each having a slot therein directed toward the radiation focus in which a collimator plate consisting of radiation absorbing material is inserted. The collimator plate is a sheet having at least one resilient tongue cut therein at each edge thereof which is received in the respective slots. The tongues are bent so as to project beyond the thickness of the plate and thus are disposed against an inside surface of the slots and thereby press the collimator plate against opposite respective surfaces of the slots.

Abstract: A shielding or masking device for use in conjunction with an X-ray radiation generating source comprised of radiopaque material having a vertically oriented opening having a broader portion twice the width of the upper, narrower portion nearer its distal or lower end to block entirely or confine radiation dosage to a specific area of a subject under observation or inspection and to prevent unnecessary and excessive radiation dosages to the subject during full spine radiographs.

Abstract: A process of X-Y lithography including providing a linearly polarized X-ray, and irradiating a resist on a substrate through a mask with the linearly polarized X-ray to form a pattern shape which is utilized for production of, for example, a semiconductor device or magnetic bubble memory device.

Abstract: An X-ray imaging system has an X-ray source, an X-ray image detection section, an X-ray mask member, a drive unit, a memory, a calculating section, and an image output unit. An X-ray image is detected by the X-ray image detection section. The X-ray mask member has X-ray shielding regions, distributed in a predetermined pattern, which locally shield the X-ray. The mask member is driven by the drive unit so that it is inserted in or removed from an X-ray radiation field between the X-ray image detection section and the X-ray source, and is sequentially displaced to predetermined positions in the radiation field. The calculating section calculates scattered X-ray intensity distribution data based on a plurality of transmission X-ray data obtained by irradiating an object with X-rays with the mask member located at different positions in the radiation field, and transmission X-ray data obtained by irradiating the object with X-rays with the mask member located outside this field.

Abstract: There is disclosed an improved control circuit for a slit radiographic apparatus wherein the slit radiographic apparatus is comprised of an X-ray source adapted to scan a body to be radiographed through a slit diaphragm with a planar fan beam wherein the slit diaphragm is divided into a plurality of attenuating sections each associated with a controllable X-ray attenuating member and wherein there is provided a detection assembly for detecting the intensity of the radiation having passed through the body and divided into sections corresponding to attenuating sections of the slit diaphragm wherein each X-ray attenuating member is controlled by the control circuit including an energizing circuit and a comparison circuit for each attenuating member of the slit diaphragm whereby the comparison circuit compares an output signal of an associated section of the detection means to a reference signal to form an output coupled to the energizing circuit to control the attenuating member of a respective attenuating secti

Abstract: An apparatus for slit radiography comprising an X-ray source by means of which a body being irradiated can be scanned through a slit diaphragm by a substantially planar, fan-shaped X-ray beam, the scanning X-ray beam passed through the body impinging upon an X-ray detector. The apparatus comprises controllable attenuation elements coacting with the slit diaphragm, each element being adapted to influence a sector of the scanning X-ray beam under the control of signals generated by a radiation detector device. The radiation detector device is disposed between the body being irradiated and the X-ray detector. The radiation detector device comprises at least one radiation detector extending at any moment into the scanning X-ray beam passed through the body and moving in synchronism with the scanning movement of the X-ray beam.

Abstract: The invention relates to a process for the controlling of the position of the focus of an X-ray tube, a applicable to the monitoring of X-ray equipment equipped with X-ray tubes and to the installation of the latter in shields. The invention also relates to a control apparatus for performing the above process. According to the process of the invention, the image of the focus of an X-ray tube is produced on two X-radiation sensitive, contiguous detector means. Each of the detector means supplied an output signal, whose amplitude is a function of the distribution of said image of said detector means. The output signals are applied to a comparison means, which supplies a difference signal linked with the position of the focus along a first given 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.