Abstract: Radiopaque marker and method for use in nuclear medicine imaging, (particularly with X-ray radiology) of soft tissue landmarks of a patient's body. The radiopaque marker includes a spherical ball of radiopaque material attached to an adhesive sheet which is positioned on a sheet of release film. Radiopaque markers are removed from the release film and applied to soft tissue landmarks on the patient. The patient's body, with the radiopaque markers, is then imaged, e.g. with X-ray radiology. The radiopaque markers leave circular shadows on the X-ray film, regardless of the contours of the portion of the body to which the radiopaque markers are applied, and can be used to accurately mark soft tissue landmarks.

Abstract: X-ray tube with an anode and a cathode arranged in a vacuum housing has two getters in the inside of the vacuum housing for bonding free gases. One getter is disposed at a location in the vacuum housing neighboring the anode at which a relatively high temperature prevails during operation, and the other getter is disposed at a location at which a comparatively low temperature prevails during operation.

Abstract: An X-ray microscope utilizing X-rays radiating from a laser-irradiated target so as to form an X-ray image of a specimen placed in a sample cell, the X-ray microscope includes a target for radiating X-rays when the same is irradiated with a laser beam, a sample cell for housing a specimen, the sample cell provided near the surface of target placed opposite to where the target is irradiated with the laser beam, and a detector for forming an X-ray image of the specimen by X-ray penetration, wherein the target, the sample cell and the detector are unified in a unit. The unit is placed at a place where the laser beam is irradiated to the target. A spacer is provided between the target and the sample cell, wherein the size of the spacer is determined depending on a distance between the specimen and the target. With this construction, this facilitates the fabrication of the unit.

Abstract: A synchrotron exposure includes a synchrotron radiation source for generating a synchrotron radiation beam, and exposure unit having a mask stage for holding a mask and a wafer stage for holding a waver, a beam port for directing the radiation beam to the exposure unit, a mirror unit having a mirror for reflecting the radiation beam, a pre-alignment system for aligning the wafer relative to the wafer stage, a fine-alignment system for aligning the wafer held by the wafer stage relative to the mask held by the mask stage, a mask storage apparatus for storing the mask, a wafer storage apparatus for storing the wafer, a mask conveying apparatus for conveying the mask between the mask storage apparatus and the mask stage and a wafer conveying apparatus for conveying a wafer between the wafer storage apparatus and the wafer stage.

Abstract: X-ray masking apparatus includes a frame having a supporting rim surrounding an x-ray transparent region, a thin membrane of hard inorganic x-ray transparent material attached at its periphery to the supporting rim covering the x-ray transparent region and a layer of x-ray opaque material on the thin membrane inside the x-ray transparent region arranged in a pattern to selectively transmit x-ray energy entering the x-ray transparent region through the membrane to a predetermined image plane separated from the layer by the thin membrane.

Abstract: X-ray microscopy is used to observe a specimen by labelling the specimen with a molecule having a double bond, such as, for example, N-succinimidyl-4-nitrophenyl acetate or 5-(dimethylamino phenyl)-2,4-pentadienal, which bond to an amino group, and O-(4-nitrobenzyl)-N,N-diisopropyl isourea, which chemically bonds to a carbonyl group. Such labelling groups can generate fluorescence to facilitate the observation of the specimen. Observation is improved by using a monochromatic X-ray source having a photon energy lower than 2000 eV and a band width narrower than 1 eV.

Abstract: An damascene x-ray mask comprises an oxide membrane layer having trenches formed therein defining an x-ray mask pattern. The trenches are filled with collimated, sputtered tungsten sputtered in a relatively high pressure environment. The result is a dense, low stress tungsten film completely filling the trenches. Damascene refers to the process by which the mask is formed. The mask is formed on a silicon substrate and then the substrate is etched away from the bottom side leaving substantially just the oxide layer and the collimated tungsten. The oxide layer is transparent to x-rays and the collimated tungsten layer is opaque to x-rays.

Abstract: A fluorescent X-ray analyzing apparatus includes a source of excitation (2) for irradiating a silicon-based sample (S) with primary X-rays (B2) to excite the silicon-based sample (S), a detector (4) for detecting fluorescent X-rays (B5) emitted from the silicon-based sample (S), and an analyzer (6) for analyzing elements contained in the silicon-based sample (S) based on a result of detection performed by the detector (4). The primary X-rays (B2) emitted from the source of excitation (2) have a wavelength higher than, but in the vicinity of a wavelength at an Si--K absorption edge so that generation of fluorescent X-rays (B5) of Si is suppressed to minimize a noise which would occur during detection of fluorescent X-rays (B5) of Na and Al to thereby accomplish an accurate analysis of a minute quantity of NA and Al contained in the sample (S).

Abstract: A method and apparatus to facilitate avoiding failure of a computed tomography x-ray source while performing a patient scan permits detection of the onset of a potential x-ray source failure and estimation of the x-ray source life expectancy. The information obtained can be used in deciding whether to repair or replace an x-ray source prior to failure. In one embodiment, signals I(x,y) representative of the x-ray beam optical focal spot detected by a detector array are sampled, and a wavelet transform is applied to the sampled signals I(x,y) to generate at least one energy level F.sub.new for a wavelet band. The energy level P.sub.new is compared with stored energy levels P.sub.stored to identify one of the energy levels P.sub.stored which, when subtracted from energy level P.sub.new, results in a statistically non-significant value. The remaining life of the x-ray source is estimated as being equal to the life expectancy value corresponding to the identified energy level P.sub.stored.

Abstract: An improved x-ray laser aiming system providing coaxial laser aiming in a configuration opposed to the x-ray emitter is disclosed. The present invention comprises two basic components: 1) a laser sight coupled to an x-ray emitter, and 2) a laser device assembly coupled to an x-ray collector. The laser sight provides a means for aligning the x-ray emitter with a laser beam during surgical or diagnostic procedures. The laser device assembly is removably coupled to the image intensifier or x-ray collector. The laser device assembly contains a point laser source and a fixed reflective surface or mirror for directing a laser beam coaxially with the center ray of the x-rays emitted by the x-ray emitter, but in the opposite direction. The laser source is, therefore, in a configuration opposed or opposite to the x-ray emitter.

Abstract: An anatomic X-ray phantom having two layers of radiolucent material, at least one layer of metallic material therebetween, and a test pattern. The metallic layer is of a shape regionally similar to a corresponding human anatomy portion and has X-ray absorptive characteristics similar to the corresponding human anatomy portion. The test pattern is for X-ray quality assurance testing of the imaging system and is positioned inside the phantom in an area having radiopacity/radiolucency characteristics similar to the corresponding human anatomy portion. Other metallic layers also may be disposed between the two radiolucent layers. Preferably, the test pattern is directly adhered to a metallic layer on the side thereof facing the direction of the source of X-ray photons from the X-ray system.

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: An apparatus for orienting, securing and analyzing a specimen comprises a base for receiving the specimen. A cover is receivable over the specimen and base, and an adjustable mechanism is provided for securing the cover to the base. The apparatus further comprises a mechanism, disposed on at least one of the base and cover, for identifying a discrete, localized area on the specimen.

Abstract: A collision-free control system comprising a multi-axially controllable manipulator having interconnected supporting arms which are movable by way of actuators in such a way that a free end of the manipulator can be positioned spatially and moved into various positions. The actuators are controlled via a miniature model of the manipulator which is operated manually and is equipped with a series of position transducers which are capable of delivering control signals for commanding the actuators in such a way that the manipulator and the miniature model thereof always assume identical positions.

Abstract: Local tomography is enhanced to determine the location and value of a discontinuity between a first internal density of an object and a second density of a region within the object. A beam of radiation is directed in a predetermined pattern through the region of the object containing the discontinuity. Relative attenuation data of the beam is determined within the predetermined pattern having a first data component that includes attenuation data through the region. In a first method for evaluating the value of the discontinuity, the relative attenuation data is inputted to a local tomography function .function..sub..LAMBDA. to define the location S of the density discontinuity. The asymptotic behavior of .function..sub..LAMBDA. is determined in a neighborhood of S, and the value for the discontinuity is estimated from the asymptotic behavior of .function..sub..LAMBDA.. In a second method for evaluating the value of the discontinuity, a gradient value for a mollified local tomography function .gradient..

Abstract: A process is disclosed which involves automatic position-finding for a point of interest of an object that exhibits high contrast as compared with surrounding tissues, the process being carried out by means of a stereotactic photographic device that includes a digital image acquisition system. The process includes a number of steps for each image belonging to the pair of stereotactic images. An initial analysis of a histogram of the image pixels are made, and a subsequent determination is made of a threshold corresponding to the difference between the high contrast objects and the surrounding tissues. A subsequent determination is made of the threshold of the image, in order to obtain a binary image incorporating two gray levels. This is followed by the filtering of the threshold determined image in the preceding step, based on morphological criteria of the object in which the point of interest is located. This operation is designed to obtain a segmented projection of the object of interest.

Abstract: Local tomographic data is used to determine the location and value of a discontinuity between a first internal density of an object and a second density of a region within the object. A beam of radiation is directed in a predetermined pattern through the region of the object containing the discontinuity. Relative attenuation data of the beam is determined within the predetermined pattern having a first data component that includes attenuation data through the region. The relative attenuation data is input to a pseudo-local tomography function, where the difference between the internal density and the pseudo-local tomography function is computed across the discontinuity. The pseudo-local tomography function outputs the location of the discontinuity and the difference in density between the first density and the second density.

Abstract: A method and system for suppressing artifacts in a CT generated image are described. With respect to artifacts resulting from X-ray beam photon starvation conditions, and in accordance with one embodiment of the method, the steps of determining a minimum value X-ray beam flux for a projection data set and dynamically DC adjusting the projection data based on the determined minimum X-ray beam flux are performed.

Abstract: The fluorescent X-ray generated by elements when an X-ray is total reflected from a substrate surface is detected by a fluorescent X-ray detecting circuit; the fluorescent X-ray peak generated by the substrate element and the fluorescent X-ray peaks generated by contaminative elements are separated by a peak separating circuit; an integral intensity I.sub.0 of the fluorescent X-ray peak generated by the substrate element and integral intensities I of the fluorescent X-ray peaks generated by the contaminative elements are calculated by an integral intensity calculating circuit, respectively; and contaminative element concentrations N=N.sub.0 .multidot.(.eta..sub.0 / I.sub.0).multidot.(I / .eta.) (where N.sub.0 denotes the surface concentration of the substrate; .eta..sub.0 denotes the fluorescent yield of the substrate; and .eta.

Abstract: A method and an apparatus for inspecting a soldered joint with an X-ray, the soldered joint being formed by soldering a lead to a surface of a substrate.

Abstract: A method and system for extending the service life of an x-ray tube wherein the coolant fluid which is circulated through a closed circulation system to remove heat generated by the x-ray tube and provide electrical insulation between anode connections and ground (and/or cathode connections) is regularly changed based on predetermined criteria. In addition to the fluid change, an on-line fluoroscopy is also regularly performed based on a separate set of predetermined criteria.

Abstract: A laser targeting device for use during surgical procedures provides means for the precise co-axial alignment of a narrow laser beam with an x-ray beam. The device has a case which contains a reflecting mirror mounted at 45.degree. on a low mass assembly. The mirror lies directly in front of a radio-opaque cruciform target. The case is adjustably mounted so that the image of the crosshair target may be accurately centered on the target head. A calibration aid is used to pinpoint the emanation point of the x-ray beam from the source cone of the image intensifier. The angle at which the laser beam strikes the mirror may be varied in two planes. When the crosshair image is centered and the laser beam is directed onto the emanation point the two beams are rendered precisely co-axial. Accurate drilling along the laser beam path without further recourse to x-ray screening is more accurate and eliminates direct exposure of the surgeon to irradiation during orthopedic procedures.

Abstract: A grid for use in a collimator system for high energy waves such as X-rays and gamma rays includes a silicon base in which slits are etched along multiple separated lines. Located transversely in the slits are tungsten slats. Between the separated lines, silicon is removed by etching. Pairs of grids are longitudinally spaced apart along a longitudinal axis running transversely to the direction of the lines and the slats. Rotating the pair of grids about the longitudinal axis, and providing a detector associated with each grid pair provides for metering high energy rays.

Abstract: An X-ray exposure mask comprises an X-ray transmission layer and an X-ray absorption layer formed on the X-ray transmission layer and being patterned. The X-ray absorption layer has a first region having a first thickness and a second region having a second thickness less than the first thickness.

Abstract: A exposure apparatus for a semiconductor wafer, a liquid crystal display panel and so on. The exposure apparatus comprises a light source, a holding means and a moving means. The light source exposes a target such as a semiconductor wafer, a liquid crystal display panel and so on. The holding means alternately holds and releases the target. The moving means for moving the holding means includes a table and a shifting means. The table moves in the direction of the light source. The shifting means shifts the holding means toward or against the table.

Abstract: A small, low cost, low power, and portable x-ray source that produces an x-ray flux that is sufficient to produce high quality x-ray images on suitable x-ray sensitive films. The source includes a vacuumated chamber that is filled with a heavy atomic weight gas at low pressure and an x-ray emitter. The chamber is in a magnetic field and an oscillating electric field and generates an Electron Cyclotron Resonance (ECR) plasma having a ring of energetic electrons inside the chamber. The electrons bombard the x-ray emitter which in turn produces x-ray radiation in a given direction. A pair of magnetic members generate an axisymmetric magnetic mirror trap inside the chamber. The chamber may be nested within a microwave resonant cavity and between the magnets, or the chamber and microwave cavity may be a single composite structure. The source is useful to make x-ray photographs virtually anywhere and may be battery powered.

Abstract: An X-ray apparatus includes a frame (1, 3, 5) which supports at least an X-ray source (7) and an X-ray detector (9) and is attached to a base (13) which is provided with wheels (19, 21) enabling displacement of the apparatus on an approximately horizontal floor surface. In order to prevent cables lying on the floor from colliding with the wheels (19, 21) during displacement, so that the wheels could be blocked, each of the wheels (19, 21) includes a cable deflector which consists of an approximately horizontally arranged collar (25) which is made of a rigid material and which encloses the wheel at a distance of less than 10 mm from the floor surface (39).

Abstract: The present invention provides a method for positive product identification using tagging materials such as barium sulfate, manganese dioxide or mixtures thereof. Such materials may be employed, for example, in the dusting agent used in roofing materials, and applied to one or both sides of rubber roofing sheeting or admixed with the compounding ingredients during the preparation of the sheeting composition. The tagging materials can be detected and identified in the finished product by X-ray fluorescence spectroscopy.

Abstract: A source of gamma rays (a photon beam) at a single energy produced by the single-quantum annihilation of accelerated positrons with electrons of a target element. The photons are emitted predominantly in the forward direction and are accompanied by background radiation which can be differentially suppressed. The energy of the photons is determined by varying the energy of incident positrons. The photon beam is usable in materials research and analysis, medical diagnosis and therapy, and numerous other fields.

Abstract: An x-ray film changer includes a removably mounted, passive-type cassette having no film driving mechanism and comprising a film-receiving spiral guide plate extending within the cassette in excess of one and one-half 360.degree. turns. The cassette further comprises an anvil bar for reverse bending of the guide plate when the cassette is opened, to facilitate film removal, a light-blocking gate which uncovers a film feed-in slot in response to mounting of the cassette on a film exposure device, and a combination carrying handle-latch mechanism.

Abstract: Long-wavelength light is introduced into an electron orbit capable of storing high-speed electrons to produce inverse Compton scattering to scatter short-wavelength light to provide short-wavelength light. The introduced long-wavelength light is repeatedly reflected and repeatedly touches the electron orbit. The effective collision cross section of the introduced light with electrons can be substantially increased by increasing the number of collisions. Sufficiently short-wavelength light can be obtained by a small-sized apparatus without making the electron energy very high.

Abstract: An x-ray source propagates radiation across an examination gap onto a intensifier tube input screen. The output screen of the intensifier tube is viewed by a video camera. A sampling means is disposed between the intensifier output screen and the video camera. The sampling means views the intensifier output screen and converts the viewed image into an electronic control signal for the x-ray source. The sampling means includes a first block pivotally secured to a second block below a receiving hole in the first block. The blocks are adjustably biased in pivoting tension about a pivot below the receiving hole. A barrel is frictionally engaged in the receiving hole. One end of the barrel is angled on one side and cutout on the other side. A mirror is fixedly disposed on the angled side such that light propagating through the cutout is reflected through the central axis of the barrel to a photo diode fixedly disposed at the other end of the barrel.

Abstract: Proposed is a high-precision X-ray lithographic mask blank with reinforcement free from warping or distortion. The mask blank is an integral body comprising: (a) a frame made from a silicon wafer; (b) a membrane of an X-ray permeable material such as silicon carbide adhering to and supported by one surface of the frame; and (c) a reinforcing member made from a single crystal of silicon adhesively bonded to the other surface of the frame with (d) a layer of silicon oxide intervening between the frame and the reinforcing member. The mask blank can be prepared in a process of first forming a layer of silicon oxide on the surface of the silicon wafer and/or reinforcing member prior to deposition of the X-ray permeable film on the silicon wafer and heating them together at a temperature of 800.degree. C. or lower while they are in direct contact with each other with the silicon oxide layer intervening therebetween.

Abstract: An X-ray exposure method and apparatus wherein an exposure chamber coupled with a synchrotron radiation device through a beam line receives synchrotron radiation through a window material provided on the beam line to execute an exposure process, a pressure sensor detects pressure in the exposure chamber, a cutoff valve is provided in a portion of the beam line between the window material and the synchrotron radiation device, and a bypass has a communication valve for communicating a portion of the beam line between the window material and the cutoff valve with a portion between the window material and the exposure chamber.

Abstract: A method for the manufacture of semiconductor devices wherein a radiation beam including first and second beams is projected from a synchrotron orbit radiation source into an ambience maintained substantially at a vacuum, includes the steps of directing the radiation beam to a wafer through a window effective to isolate the ambience to thereby print a circuit pattern on an X-ray sensitive layer on the wafer with the first beam, providing a support for supporting the window having an opening, extracting the second beam through the opening, and detecting and correcting any deviation of the first beam with respect to the wafer.

Abstract: A multispectral variable magnification glancing incidence x-ray telescope capable of broadband, high resolution imaging of solar and stellar x-ray and extreme ultraviolet radiation sources includes a primary optical system which focuses the incoming radiation to a primary focus. Two or more rotatable mirror carriers each providing a different magnification are positioned behind the primary focus at an inclination to the optical axis, each carrier carrying a series of ellipsoidal mirrors each having a concave surface coated with a multilayer (layered synthetic microstructure) coating to reflect a different desired wavelength. The mirrors of both carriers are segments of ellipsoids having a common first focus coincident with the primary focus. A detector such as an x-ray sensitive photographic film is positioned at the second respective focus of each mirror so that each mirror may reflect the image at the first focus to the detector at the second focus.

Abstract: An X-ray microscope is provided with an X-ray source, a converging optical system collecting radiation emitted from the X-ray source, a stage on which an object is placed, and a detector having sensitivity with respect to radiation of wavelengths ranging from an X-ray region to a vacuum ultraviolet ray region, in which a filter eliminating long wavelength components from the radiation emitted from the X-ray source is disposed in an optical path from the X-ray source to the detector. Whereby, the X-ray microscope has important advantages in practical use that radiation of a desired wavelength region can be sensitively detected from the X-ray source, without bringing about large size and high cost of the optical instrument even where the X-ray source is used as a radiation source for white light.

Abstract: An X-ray lithography mask comprising a X-ray transparent film made from diamond, X-ray absorber patterns deposited on the X-ray transparent film and diamond crosspieces shaped on the diamond X-ray transparent film for reinforcing the diamond X-ray transparent film. Since both the transparent film and the reinforcing crosspieces are made from diamond, no thermal stress is induced by the change of temperature. The mask excels in transmittance for X-ray, flatness and strength.

Abstract: A high resolution x-ray microscope for imaging microscopic structures within biological specimens has an optical system including a highly polished primary and secondary mirror coated with identical multilayer coatings, the mirrors acting at normal incidence. The coatings have a high reflectivity in the narrow wave bandpass between 23.3 and 43.7 angstroms and have low reflectivity outside of this range. The primary mirror has a spherical concave surface and the secondary mirror has a spherical convex surface. The radii of the mirrors are concentric about a common center of curvature on the optical axis of the microscope extending from the object focal plane to the image focal plane. The primary mirror has an annular configuration with a central aperture and the secondary mirror is positioned between the primary mirror and the center of curvature for reflecting radiation through the apertture to a detector.

Abstract: A manually operable device for detecting wood pole decay and a method of using the same are disclosed. A gamma ray emitter is provided with guide means enabling it to be piloted longitudinally along the wooden pole so that gamma rays from the emitter pass diametrically through the wooden pole along a longitudinal axis of the pole. The attenuation of the gamma rays are continuously recorded along the longitudinal axis, and a permanent record of the variation in gamma ray attenuation is made, from which it can be determined whether the pole is healthy or decayed, and if decayed, the location of the decay along the pole. In order to facilitate locating decay in the pole, the guide means includes an odometer programmed to provide an electrical pulse every 15 cm which is recorded with the data of gamma ray attenuation. Once data on gamma ray attenation has been recorded along one longitudinal axis of the pole, the device may be used on a longitudinal axis at 90.degree.

Abstract: A device for warming at least a portion of the top surface of a bucky table of a mammography machine is provided. The device has two substantially parallel, spaced apart, heat-conductive plates adapted to be removably placed onto the table. A heating pad is placed between the two plates for warming at least a portion of the upper surface of the table. Means are provided for releasably holding the plates together so that the heating pad can be placed between the plates and removed therefrom.

Abstract: A catheter position indicator for use with leveling devices adapted for use in hemodynamic monitoring. The indicator includes a radio transparent sheet material containing a plurality of spaced apart radio opaque material portions. Also included is a means for fastening the sheet material to a human body. An X-ray may be taken so that the location of a catheter may be determined in relation to the radio opaque portions of the radio transparent sheet material. Once the location of the catheter is determined a simple bubble level device may be utilized to bring a hemodynamic transducer assembly into level with the inserted catheter.

Abstract: A mobile X-ray apparatus for use in X-ray in diagnostic examinations comprising a base on wheels having an arm structure mounted thereon for supporting an X-ray tube, wherein this arm structure comprises a first structure of telescopic construction utilizing a pulley principle for an extended vertical travel of the X-ray tube and yet compactness, and further including a constant spring mechanism for allowing manual positioning, a second structure moveably mounted on the first structure for both horizontal and vertical displacement of the X-ray tube which structure includes a parallelogram and a horizontal telescopic member, a steering assist mechanism including motors providing power to each wheel of one pair of the wheels and being independently energized so that a power differential can be created as desired to assist in turning the apparatus. This disclosure further includes a brake mechanism for effective control of positioning of any moveable structure of an X-ray apparatus.

Abstract: Methods and apparatuses in mammographic photography, wherein the breast (M) to be photographed is pressed and spread between holders (6,7) attached to the photographing apparatus. A beam (R) of X-radiation is directed from one side of the holders (6,7) through the breast (M) placed between the holders at depicting means (21) placed at the opposite side of the holders in relation to the source (2) of X-radiation, said depicting means being placed inside a film cassette or equivalent placed in connection with the frame of the apparatus. In order to carry out the photography of a breast (M.sub.1 ; M.sub.2 ;M.sub.3) in different projections (f;g;h), the frame part (25) of the apparatus, in which the source (2) of radiation, the depicting means (21), as well as the breast holders (6,7) are fitted, is turned around such an axis (b--b) as substantially coincides with the central axis (a--a) of the breast (M) to be photographed, which is being pressed by the breast holders (6,7).

Abstract: An apparatus provided with a measuring head for determining with the aid of X-ray fluorescence or X-ray absorption measuring techniques the surface weight of a measuring subject comprising coatings or surface-deposits or the concentration of basic substances in the subject to be measured, comprising liquid, slurries, powder or solid samples. The apparatus includes means for moving the measuring head (1) over the subject (5) to be measured and also over a reference sample (4), such as a sample or an empty sample-container, or vice versa. The measuring aperture provided in the measuring head (1) is covered with a protective film (7) for the purpose of preventing the ingress of particles from the subject (5) into the aperture. Means (3) are also provided for checking the dirt-coating on the protective film (7) regularly and for sending an order to a film-carrying device (8, 10, 11) to advance film when the dirt-coating is found unacceptable.

Abstract: Provided are an X-ray mask support member, an X-ray mask, and an X-ray exposure process using the X-ray mask, that can effectively prevent the phenomenon of electrostatic attraction or contact of X-ray masks by appropriately disposing an X-ray mask support membrane in an exposure apparatus that employs soft X-rays. A high precision alignment can be performed.

Abstract: The modulation transfer function of a digital imaging system is measured using a test object comprising a number of slits. The effect of geometrical distortions on the MTF measurement, is minimized by making the dimension of the test object as small as possible with respect to the image detector. The minimum slit spacing d enabling suitable MTF measurement is expressed in the number of pixels N over a dimension L of the image detector: d>8L/N.

Abstract: A fluid controlled counterbalance and power-assist system for use in a diagnostic x-ray imaging system includes a first member and a second member movably mounted to said first member. A slave actuator including a reciprocal piston is selectively coupled between the first and second members. Fluid coupling ports are located on each end of the cylinder for coupling working fluid to either side of the piston. First and second master actuators each including a cylinder are located remote from the imaging system. Each master actuator has fluid coupling ports selectively located on each end of its cylinder for coupling working fluid to one side of the cylinder and control fluid to the other side. Working fluid connection lines connect one end of the slave actuator to one end of the first master actuator and connect the opposite end of the slave actuator to the second master actuator for providing working fluid flow between said actuators.

Abstract: In the electroerosive working or machining of electrically slight or non-conducting workpieces, the workpieces are made electrically conductive, at least in parts of an electroerosion working zone, by means of the supply to the workpieces of electromagnetic energy. As a result, the valency band of the atoms of the workpiece is raised, which produces therein the electrical conductivity.

Abstract: A system for the suppression of noise and its variations for the detection of a pure signal in a measured noisy discrete signal. The system measures a counting rate N.sub.2 in a signal channel and a counting rate N.sub.3 in a reference channel, evaluates the estimation value .lambda..sub.E of the ratio .lambda. between the mean noise levels in the channels and evaluates the associated false detection probability I as a function of (N.sub.2, N.sub.3 .lambda..sub.E). The system then performs a comparison of I with at least one information threshold I.sub.m, each associated with a predetermined false detection level. Comparison can take place indirectly on a function of the probability and can use tabulated values. The system has particular application to the detection of corpuscular radiation.