Abstract: In order to realize accurate analysis with a fluorescent X-ray analyzer characterized by being non-destructive and non-contacting, in a short period of time, there is provided a common X-ray generating source, a collimator for focusing primary X-rays, and, as an energy dispersion type X-ray detection system for analyzing fluorescent X-rays as a means of elemental analysis, an energy dispersion type detector where a sensor with a low count rate but having superior energy resolution and a sensor with poor energy resolution but having a superior count rate are juxtaposed.

Abstract: The invention relates to a method for fluorescent X-ray analysis of a sample, which sample includes: a substrate (5) containing a chemical element b; a thin layer (6) which is deposited on the substrate and contains the chemical element b and a chemical element a, which method includes the steps of: irradiating the sample by means of primary X-rays, detecting the intensity of X-ray lines of comparatively hard fluorescent X-rays and comparatively soft fluorescent X-rays, both produced in the sample due to irradiation by means of the primary X-rays, wherein one or more of the following combinations of the fluorescent X-ray lines of the chemical elements a and b are detected: b-L/b-K; b-K/a-L; b-L/a-L; b-L/a-M; a-M/a-L a-M/a-N a-K/b-K a-K/b-L a-K/a-L; and the thickness of the thin layer (6) and/or the concentration of the first or the second chemical element are detected on the basis of the detected X-ray lines of the comparatively hard and the comparatively soft fluorescent X-rays.

Abstract: In order provide an energy dispersive X-ray analyzer that can perform efficient measurement by optimizing signal processing time of an X-ray counting section, an energy dispersive X-ray analyzer is provided with an energy dispersive X-ray detector, an X-ray counting section for analyzing the signal from the energy dispersive X-ray detector and generating a frequency distribution for each energy level, namely an energy spectrum, and a data control section for performing data processing, user interface etc. The X-ray counting section of the energy dispersive X-ray analyzer has signal processing methods with different processing times for a single X-ray input, and a function for selecting which method result to make use of using input X-ray energy.

Abstract: A data processor for fluorescent x-ray spectroscopy calculates theoretical x-ray intensity which is theoretically expected to be obtained by a fluorescent x-ray spectroscopy measurement of a standard sample with known composition by taking into account the effects of x-ray attenuation by the possible presence of an environmental gas along the optical path of the x-rays between the x-ray tube and the sample and between the sample and the detector. The element sensitivity for each of elements in the standard sample is obtained from this calculated x-ray intensity and the intensity actually measured and is stored in a memory. When a fluorescent x-ray spectroscopy measurement is carried out on an unknown sample, the sample is quantitatively analyzed, a theoretically calculated x-ray intensity obtained also by taking into account the effects of x-ray attenuation by an environmental gas is used together with the actually measured x-ray intensity and the element sensitivities stored in the memory.

Abstract: A fluorescent x-ray analyzer has a light-dispersing crystal and a detector which are rotatable while maintaining a specified angular relationship between them such that fluorescent x-rays from a sample are scanned. A first-order profile and a higher-order profile showing x-ray intensities against scan angle are produced from detection signals from the detector respectively within a different specified range of wavelengths. Data related to ratios between preliminarily measured peak intensities of diffracted beams of first-order and higher-order obtained from a plurality of elements are stored and used to identify peaks in these profiles, if there is a possibility of a peak formed by a first-order spectrum of one element and a higher-order spectrum of another element overlapping each other and the nature and extent of contributions to the peaks in the profiles from the first-order and higher-order spectra are determined.

Abstract: A system and process for classifying a piece of material of unknown composition at high speeds, where the system connected to a power supply. The piece is irradiated with first x-rays from an x-ray source, causing the piece to fluoresce x-rays. The fluoresced x-rays are detected with an x-ray detector, and the piece of material is classified from the detected fluoresced x-rays. Detecting and classifying may be cumulatively performed in less than one second. An x-ray fluorescence spectrum of the piece of material may be determined from the detected fluoresced x-rays, and the detection of the fluoresced x-rays may be conditioned such that accurate determination of the x-ray fluorescence spectrum is not significantly compromised, slowed or complicated by extraneous x-rays. The piece of material may be classified by recognizing the spectral pattern of the determined x-ray fluorescence spectrum. The piece of material may be flattened prior to irradiation and detection.

Abstract: A fluorescent X-ray analyzing apparatus capable of being used as either a wavelength dispersive type or an energy dispersive type is provided, with which the analysis can be performed quickly and accurately. The fluorescent X-ray analyzing apparatus includes a detecting unit for detecting and analyzing fluorescent X-ray (5) emitted from at least one target area (1a) of a sample (1) to be analyzed as a result of excitation of such target area (1a) with a primary X-ray (3). The detecting unit includes a wavelength dispersive type detecting unit (6) including a spectroscope (8) and a first detector (9), and an energy dispersive type detecting unit (11) including a second detector (12) of an energy dispersive type.

Abstract: The invention relates to a device for X-ray analysis with energy dispersive detection of fluorescent radiation. In order to enable the measurements to be carried out with a suitable position resolution, the analyzing radiation is conducted to the sample (4) by means of an X-ray conducting capillary (6) which is directed to the sample through the detector surface (14). Practically all fluorescent radiation (30) from the sample can be detected in such arrangement. According to the invention a detector is used in the form of an X-ray-sensitive CCD array (12). Such a CCD array provides a better energy resolution in comparison with conventional EDX detectors. Moreover, for such CCD arrays a large amount of sophisticated software is available for reading out; moreover, such CCDs can be readily purchased, for example, as rejected visible light sensitive arrays in which a small number of pixels have dropped out.

Abstract: In order to achieve suitable positional resolution for an angular scan in Grazing Exit X-ray Fluorescence (GEXRF), the sample (2) should be irradiated with a small spot (14). Consequently, the fluorescent radiation yield is low so that the duration of a measurement is comparatively long. In order to mitigate this drawback, the invention proposes the use of an analyzing X-ray mirror (16) having a line focus (22) extending perpendicularly to the sample surface (4). The line focus (22) coincides with a line-shaped PSD (24), so that every position on the PSD corresponds to a given height on the mirror, which height itself corresponds to a given take-off angle of the fluorescent radiation relative to the sample surface. Excellent positional resolution and an attractive fluorescent radiation yield are obtained by irradiating the sample by way of a focused electron beam.

Abstract: An X-ray analyzing apparatus includes a drive unit for moving a sample, a plurality of field-limiting slits each having a slit size corresponding to the size of a measuring area of the sample, a selector unit for selectively bringing the field-limiting slits into a path of travel of the secondary X-ray between the sample and the detecting unit, a drive controller for controlling the drive unit to move the sample according to the size of the measuring area of the sample to a position at which the intensity of radiation of a primary X-ray towards the measuring area of the sample attains a maximum value; and a selector controller for controlling the selector unit to render only the secondary X-ray emanating from the measuring area of the sample to be incident upon the detecting unit.

Abstract: A fluorescent x-ray spectrometer, which can be used selectably both as a wavelength-dispersion type and an energy-dispersion type, includes an irradiation chamber and a detection chamber provided with both a first detector and a second detector respectively for detecting wavelength-type and energy-type dispersion. A sample disposed in the irradiation chamber is exposed to excitation x-ray and generates fluorescent x-ray which is introduced into the detection chamber along an incident optical path defined by a Soller slit and is made incident on a dispersing element. For detecting wavelength-type dispersion, dispersed x-ray is received by the first detector. For detecting energy-type dispersion, the dispersing element is retracted from the incident optical path such that the incident x-ray from the irradiation chamber is directly received by the second detector, disposed on an extension of the incident optical path, without being dispersed by the dispersing element.

Abstract: A Soller slit 16 in an X-ray spectrometer can parallelize fluorescent radiation which emanates from a specimen 4 and is to be analyzed according to wavelength by an analyzer crystal 18. Because the aim is to irradiate an as large as possible surface of the specimen 4 by means of primary X-rays 10, inevitably disturbing fluorescent radiation is also generated by the environment of the specimen, for example the specimen holder 6. In order to intercept this disturbing radiation so that it cannot reach the X-ray detector, a collimator mask 12 is arranged in a fixed location in the beam path. In the case of varying specimen dimensions it is not always possible to choose such dimensions for this mask that the disturbing radiation is intercepted. Therefore, a second collimator mask 28 is provided (behind the Soller slit 16) in order to intercept the disturbing radiation in cooperation with the first mask 12.

Abstract: A method and apparatus are presented which provide non-intrusive detection of atoms of light elements (atomic numbers 3-13) on a surface of a semiconductor substrate using X-ray fluorescence (XRF). The present technique may be economically performed routinely on manufactured products. The method includes producing a monochromatic X-ray beam comprising X-ray photons with energy levels operably chosen to cause only atoms of light elements to emit secondary X-ray photons. The monochromatic X-ray beam is then focused onto a circular exposed region on the surface of the semiconductor substrate, the circular exposed region having a diameter ranging from about 0.5 mm to about 10.0 mm. Secondary X-ray photons emitted by atoms of light elements in the exposed region on the surface of the semiconductor substrate are directed to at least one X-ray detector. Each X-ray detector is aligned to receive secondary X-ray photons from a single light element, and is illuminated for a predetermined amount of time.

Abstract: An apparatus and method are presented for determining the elemental compositions and relative locations of particles on a surface of a semiconductor wafer. An exposed region of the surface of the semiconductor wafer is subjected to a beam of primary X-ray photons, and secondary X-ray photons emitted by atoms of elements on and just under the surface of the semiconductor wafer are detected by an X-ray detector array which includes multiple X-ray detectors. Each X-ray detector produces an output signal which is proportional to energy levels of incident X-ray photons. The X-ray detectors are laterally displaced from one another, and arranged to allow two-dimensional resolution of detected secondary X-ray photons emitted by atoms of elements on the surface of the semiconductor wafer. The X-ray detector array is preferably an electronic area image sensor including a two-dimensional array of photosensor elements formed upon a monolithic semiconductor substrate.

Abstract: A contaminating-element analyzing method enables precise identification of contaminating elements and precise calculation of concentrations thereof by eliminating a broad peak waveform due to Rayleigh scattering and Compton scattering and a background waveform from a measured waveform of a contaminated sample. A blank sample or samples are irradiated by an X-ray beam under a constant condition to obtain a plurality of measured waveforms of fluorescent X-rays, and the plurality of measured waveforms are averaged to obtain a blank waveform. Then a contaminated sample is irradiated by the X-ray beam under the same condition as that for the blank sample to obtain a measured waveform of fluorescent X-rays. The blank waveform is subtracted from the measured waveform of contaminated sample, and then the contaminating elements are identified and the concentrations thereof are calculated on the basis of the waveform data after the subtraction process.

Abstract: An x-ray diffraction apparatus for use in analyzing the x-ray diffraction pattern of a sample. The apparatus includes a beam source for generating a collimated x-ray beam having one or more discrete x-ray energies, a holder for holding the sample to be analyzed in the path of the beam, and a charge-coupled device having an array of pixels for detecting, in one or more selected photon energy ranges, x-ray diffraction photons produced by irradiating such a sample with said beam. The CCD is coupled to an output unit which receives input information relating to the energies of photons striking each pixel in the CCD, and constructs the diffraction pattern of photons within a selected energy range striking the CCD.

Abstract: A surface analysis method and an apparatus for carrying out the samein which the method involves the detection of fluorescence X-rays emitted from the surface of a sample in response to a finely focused electron beam irradiated thereto, whereby residues on the sample surface are analyzed qualitatively and quantitatively. An electron beam (1) is irradiated through a hole (9) at the center of an X-ray detector (8) into a fine hole (h) on the surface of a sample (2). In response, fluorescence X-rays are emitted from inside the fine hole (h) and are detected by an annular X-ray detector (8) having an energy analysis function near the axis of the electron beam (1) (preferably within 20 degrees with respect to the center axis of the electron beam). This arrangement allows the fluorescence X-rays from the fine hole (h) to reach the X-ray detector (8) without being absorbed by the substance of the material.

Abstract: An X-ray fluorescent spectrometer uses a screen which restricts a field of view to a local portion of a specimen irradiated by X-rays from an X-ray tube. Fluorescent X-rays from the specimen from the local portion and passing through the screen are collimated, dispersed and analyzed. A control unit controls a rotating mechanism to rotate the specimen or its container around a predetermined axis and also a moving mechanism to linearly move the screen such that the local portion to be analyzed and a throughhole of a proper size therefor can be brought adjacent each other. Data on the positions of local portions to be analyzed on the specimen can be inputted through an input unit. Effects of variations in detection results due to different distances between the analyzed local portions and the axis of rotation can be compensated for by storing reference data obtained from a standard sample in a data processing unit.

Abstract: In a gas ionization x-ray detector pulse-amplitude shifts will adversely affect the accuracy of the analysis. At increasing count rates a space charge building up leads to a decrease of the impact ionization in the detector thereby causing the detected pulse amplitude to become lower. By means of addressing a pulse-shift correction random-access memory with digital signals representing detected pulse amplitudes count rates pertaining to high-energy parts and low-energy parts, respectively of a peak in a pulse-height distribution are generated. A difference of count rates for a high-energy part and for a low-energy part of the same peak in the pulse-height distribution indicates pulse-amplitude shift. On the basis of the differences of the high-energy count rate and the low-energy count rate a correction signal is produced for adjusting the amplification of the pulse-amplitudes. To obtain stable operation pulse-shift correction is activated only when the count rate exceeds a threshold value.

Abstract: This invention relates to a method and apparatus for analyzing a plurality of elements that are present on the surface of a material of interest or in its neighborhood, as well as a thin-film forming apparatus that is capable of measuring the composition of a sample during thin film formation in the process of semi-conductor fabrication. The apparatus are characterized in that a detector is isolated from the light and heat generated in a sample making mechanism by means of a shield which is not only heat-resistant but also transmissive of fluorescent X-ray containing soft X-rays of 1 Kev and below and that a mirror for total reflection of X-rays which is equipped with slits capable of adjusting the incident and exit angles of fluorescent X-rays from the sample excited with an excitation source as well as the ranges of those angles is provided either at the entrance or exit of said shield or at both.

Abstract: An X-ray spectroscopic analyzing apparatus which comprises a source of X-rays, a first analyzing crystal for diffracting the X-rays from the X-ray source, and a second analyzing crystal for diffracting the X-rays from the X-ray source and also for passing therethrough a diffracted X-ray component from the first analyzing crystal. The first and second analyzing crystals are so disposed and so positioned as to permit the diffracted X-ray components of different wavelengths to travel along a single path towards a sample to be analyzed. On an optical path extending between the X-ray source and the sample, a filtering means for cutting a portion of the X-rays which has a wavelength shorter than a predetermined wavelength.

Abstract: The invention relates to an apparatus and method for detecting the presence of an element of interest within an object. The object is positioned where a beam gamma rays of the required energy are directed to be scattered by the element of interest. The gamma rays are provided by excited atoms of the element of interest. The excited atoms result from the reaction of hydrogen or heavier ions and a suitable target. The excited atoms deexcite releasing gamma rays which are scattered by the element of interest within the object. The scattered gamma rays are detected, output signals are produced, processed and analyzed to determine the amount of the element of interest within the object. A preferred embodiment relates to the detection of nitrogen-based explosives in luggage.

Abstract: A method of measuring a coating thickness applied on a target of constant base material, such coating containing a non-radioactive labelling material having an atomic number higher than 20.

Abstract: A portable x-ray fluorescence spectrometer has a portable sensor unit containing a battery, a high voltage power supply, an x-ray tube which produces a beam x-ray radiation directed toward a target sample, and a detector for fluorescent x-rays produced by the sample. If a silicon-lithium detector is used, the sensor unit also contains either a thermoelectric or thermochemical cooler, or a small dewar flask containing liquid nitrogen to cool the detector. A pulse height analyzer ("PHA") generates a spectrum of data for each sample consisting of the number of fluorescent x-rays detected as a function of their energy level. The PHA can also store spectrum data for a number of samples in the field. A processing unit can be attached to the pulse height analyzer to upload and analyze the stored spectrum data for each sample.

Abstract: An X-ray analysis apparatus comprises an analysis crystal which is cylindrically curved in the saggital direction. As a result, a beam diffracted by the crystal is collimated in that direction, i.e. the plane of incidence of the X-ray beam, so that a substantial gain regarding radiation yield is obtained without loss of resolution.

Abstract: A system for detecting the presence of known materials in a body or container. The system incorporates a gamma or X-ray source for irradiating the body with gamma rays to produce X-ray fluorescence of materials contained therein. A directionally discriminate X-ray detector is positioned to intercept X-rays emitted from the body and is adapted to pass only those X-rays having a predetermined wavelength and incident from a specific direction that are characteristic of a material of interest contained in the body. The detector includes a dislocation free single crystal having substantially parallel input and output surfaces. A second crystal aligned parallel to the first crystal may be disposed at a position offset from the first crystal to receive the X-rays transmitted by the first crystal in order to discriminate between materials fluorescing within the body. In a specific embodiment of the invention, the first detector comprises an elongated crystal which pass X-rays in accordance with the Borrmann effect.

Abstract: A method for analyzing a state of an element in a specimen comprises the steps of applying an exciting source to the element, detecting the intensity of characteristic X-rays generated from measurement points at two wavelengths previously selected depending on the state of the element to be analyzed, comparing the intensity ratio of the characteristic X-rays at the two wavelengths to detect some measurement points providing the detected intensity ratio falling within a range selected depending on the state of the element, and outputting state detection signals detected only at said some measurement points to obtain a line analysis or a two-dimensional scanning image.

Abstract: A device which measures both the thickness of a thin film and the concentration of selected elements within the thin film. An X-ray source is utilized to irradiate the thin film sample and two detectors, an energy dispersive detector and a wavelength dispersive detector, provide the film thickness and element concentration measurements respectively.

Abstract: An X-ray line detector where signals from detector elements are selectively combined in dependence on the deflection angle of the X-ray beam from the X-ray source and an object carrier.

Abstract: A non-planar, focusing mirror, to be utilized in both electron column instruments and micro-x-ray fluorescence instruments for performing chemical microanalysis on a sample, comprises a concave, generally spherical base substrate and a predetermined number of alternating layers of high atomic number material and low atomic number material contiguously formed on the base substrate. The thickness of each layer is an integral multiple of the wavelength being reflected and may vary non-uniformly according to a predetermined design. The chemical analytical instruments in which the mirror is used also include a predetermined energy source for directing energy onto the sample and a detector for receiving and detecting the x-rays emitted from the sample; the non-planar mirror is located between the sample and detector and collects the x-rays emitted from the sample at a large solid angle and focuses the collected x-rays to the sample.For electron column instruments, the wavelengths of interest lie above 1.

Abstract: A multichannel X-ray spectrometer includes an X-ray tube with a transmission target and a holder for a specimen placed opposite the target, and spectrometric channels arranged around the specimen. These spectrometric channels include, successively arranged downstream fluorescent X-rays of the specimen, a common inlet annular slit with a radius R, focusing analyzer crystals, outlet slits, and detectors of X-rays. The common annular slit is spaced from the reference surface of the holder to a distance h equal to 0.5 R, where R is 0.5 dD/2L, where d is the diameter of the outlet port of the transmission target, D is the diameter of the fo-fusing ring of the focusing analyzer crystals, and L is the length of one of the focusing analyzer crystals.

Abstract: The present invention relates to an arrangement for the non-destructive measurement of metal traces in the surface of material samples in which the surface is irradiated with X-ray radiation and a detector, fastened above the material sample, spectrometrically examines the fluorescent radiation emanating from the material sample. Metal impurities are detected in the surface of, for example, silicon wafers down to about 10.sup.11 atoms/cm.sup.2, on-line, with the wafers being free from contamination by the measuring process. It is possible to sweep the entire surface area of wafers having a diameter up to about 150 mm at the locations fixed by the respective standards. The X-ray radiation directed onto the surface of the material sample by means of an adjustable X-ray source, the divergence of the exciting X-ray radiation being limited by two aperture members, the aperture members being disposed in a quartz body serving as an optical bench.

Abstract: Improved methods and apparatus for in vivo measurement of the skeletal lead burden of a patient and for diagnosis of lead toxicity are disclosed. The apparatus comprises an x-ray tube emitting soft low energy x-rays from a silver anode, a polarizer for polarizing the emitted x-rays, and a detector for detecting photons fluoresced from atoms in the patient's tibia upon irradiation by the polarized x-rays. The fluoresced photons are spectrally analyzed to determine their energy distribution. Peaks indicating the presence of lead are identified if the patient has relatively high bone lead content. The data may be compared to data recorded with respect to a similar test performed on patients having also had the conventional EDTA chelation tests performed thereon in order to correlate the test results with respect to a particular patient to the conventionally accepted EDTA chelation test.

Abstract: A wavelength dispersive X-ray spectrometer is provided with a polycrystalline analyzer for analyzing characteristic spectra of a sample. The polycrystalline analyzer provides a multiple spectrum of characteristic lines which are separated by appropriate pulse height analysis. Each of these sets of characteristic lines of the elements of the sample are provided at different dispersion and wavelength ranges.

Abstract: X-ray dispersive and reflective structures and materials are constructed which exhibit improved characteristics in specific ranges of interest. The structures are formed of metallic and non-metallic layer pairs. The structures are formed of alternating layers of Cr:C, Ni:C or V:C for carbon analysis and Mo:B.sub.4 C for beryllium an boron analysis. The layered structures can be formed from Ni:C for analysis of both carbon and boron.

Abstract: A Dual Channel Spectrometer system is provided for measurement of X-ray spectra in which at least two pairs of crystals are arranged in a crystal changer so that different pairs of such crystals can be selected in the X-ray spectrometer. This selection is achieved by rotating a drum on which pairs of crystals are mounted about an axis to bring one pair of crystals into alignment with a collimated X-ray beam. This enables the selection of the wavelength range used in the spectrometer to be made without deactivating the spectrometer or without loosing the vacuum in the spectrometer.

Abstract: An apparatus for detecting heavy metals in an oil sample which radiates X-rays from a target type X-ray tube through an iron filter and then upon a sample cell containing the oil to be measured therein and detects fluorescent X-rays excited in the oil by an energy dispersion type fluorescent X-ray detector.

Abstract: A sample cup for use in spectroscopy consists of a cap member having an extending peripheral flange about a closed top surface, with a downwardly extending cylindrical bottom section, the peripheral flange of the cap member has a through aperture located on the inner edge of the flange and extending towards the periphery, a cell body is of a tubular configuration with an opened top and bottom with the opened top surrounded by a flange having an aperture on an inner surface for communicating with the internal hollow of the cell body. The cap member is adapted to coact with the opened top of the cell body and is rotatably supported thereon, whereby in a first mode the through aperture communicates with the cell aperture to create a vent passageway and in a second rotatable position, the apertures do not align to create a closed cell mode.

Abstract: An automatic steel analysis apparatus for analyzing the composition of steel materials by carrying out an element analysis using an X-ray excited energy dispersion type fluorescent analysis in the conveying path of the steel materials. A movable housing is vertically movably mounted below the conveying path and has a window in the top thereof closed by an X-ray permeable membrane. An X-ray tube and a semiconductor detection element are housed in the movable housing, and the detection element is connected to a computing apparatus for supplying analysis information thereto for enabling the computing apparatus to determine the composition of steel materials. An air conditioning apparatus controls the temperature and humidity within the movable housing.

Abstract: According to the method of the invention, samples undergoing analysis for sorting are irradiated one by one in order to excite X-ray fluorescence. In order to take into account the background radiation, the quality whereof varies according to the frequency of the excited radiation, the radiation peak intensity I.sub.1 is measured, as well as the respective intensity I.sub.2 is measured at the same point of the radiation spectrum but in an essentially wider frequency range than the radiation peak. On the basis of the measured intensities I.sub.1 and I.sub.2 are defined the intensities of the X-ray fluorescence F and the background radiation T, and the ratio of these two is used as the selective criterion when sorting the analyzed samples.

Abstract: A sequential x-ray spectrometer has a curved analyzer crystal and a position-sensitive detector. In order to obtain a high quantum yield or efficiency, an extensive suppression of scattered background radiation, and an increase of the measuring speed, the position-sensitive detector is arranged in a mobile fashion.

Abstract: In an X-ray analysis apparatus, a pulse amplitude shift correction circuit is provided for producing correction signals which are a measure of pulse amplitude shifts and which are in response to the pulse amplitude shifts. This circuit provides automatic correction of pulse amplitude shifts so that the pulse amplifier of the device is controlled.

Abstract: Apparatus for providing X-rays (11) to an object (12) in air. A lens (13) directs energy (14) from a laser (27) onto a target (15) to produce X-rays (11) of a selected spectrum and intensity. A substantially fluid-tight first enclosure (16) around the target (15) has a pressure therein substantially below atmospheric pressure. An adjacent substantially fluid-tight second enclosure (18) contains helium (24) at about atmospheric pressure. A wall (19) has an opening (20) large enough to permit X-rays (11) to pass through and yet small enough that gas (21) can be evacuated from the first enclosure (16) at least as fast as it enters through the opening (20) at the desired pressure. Intermediate enclosures (34, 34') at logarithmically increasing air pressures have similar openings (20', 20") in line with the opening (20) and a transparent portion (36) in the near wall (35) of the second enclosure (18).

Abstract: A two crystal detection system is provided for the measurement of X-ray spectra in which two half crystals are arranged at a fixed angular difference and each crystal is read out by a separate gas detector. In such a structure, both short "d" and long "d" spacings may be simultaneously measured. This construction of the present invention yields two integrated scanning channels in which both wavelength spectra can simultaneously be achieved.

Abstract: Macroanalyzer system comprising in combination: a crystal for separating X-ray emitted from a sample, an X-ray detector for detecting X-ray which are separated by the crystal, and a solar slit member located between the crystal, sample and X-ray detector. An operation circuit receives the output of said X-ray detector to eliminate the effect of the X-ray passing through the solar slit.

Abstract: Apparatus (10) for obtaining fluorescence laser EXAFS (Extended X-ray Absorption Fine Structure). A lens (12) directs a pulse of radiant energy (13) onto a metal target (15) to produce X-rays (16). A baffle (17) directs the X-rays (16) onto a spectral-dispersive monochromator (18) which directs the spectrally-resolved X-rays (16R) therefrom onto a sample (11). Fluorescence X-rays (27) from the sample (11) strike a phosphor (26) on a grid (19). Emitted light (21) from the phosphor (26) corresponds spatially to the spectral resolution of the X-rays (16R). Emitted light intensity at a point along the spatial distribution corresponds to the absorption characteristics of the sample (11) at a particular wavelength of the incoming X-rays (16R). An imaging lens (20) directs the emitted light (21) onto photographic film or an array detector (22).

Abstract: An X-ray fluorescence spectrometer comprising an X-ray source, a sample holder spaced from the X-ray source at a distance which ensures the illumination of the central portion of the sample not less than 0.3 ZU erg./s.cm.sup.2.w, where Z is the atomic weight of material of the X-ray anode and U is the voltage across the X-ray source, in kilovolts. The spectrometer further comprises a curved analyzing cristal for focusing the fluorescent radiation of the sample at an X-ray detector. The analyzing cristal and the detector are installed in an evacuated chamber. The X-ray source and the sample holder are positioned outside the evacuated chamber which has a window for passing X-ray radiation. The sample holder is positioned so that the average distance between the sample surface portion which produces radiation incident on the analyzing cristal and the window does not exceed the distance between said sample surface portion and the focus of the X-ray source.

Abstract: A scintillator formed of a ZnWO.sub.4 single crystal having an absorption coefficient less than or equal to 1.8 cm.sup.-1 for the light having a wavelength of 520 nm is disclosed which has a luminescence wavelength of 480 nm and therefore can be combined with a photodiode, and which is high in radiation detection sensitivity, short in decay time, and specifically suitable for use in computed tomography.

Abstract: A method of measuring the content of a given element in a sample by means of X-ray radiation. The sample is first irradiated with primary radiation of a given wave length, to excite first composite fluorescent radiation from the sample whose content of said element is to be determined. Subsequent hereto the sample is then irradiated with primary radiation having a shorter wave length than the first mentioned radiation, to excite a second fluorescent radiation from said sample. The magnitude of the first fluorescent radiation is then subtracted from the magnitude of the second fluorescent radiation, whereat the difference therebetween constitutes the intensity of fluorescence radiation of the shortest wave length which can be excited by the primary radiation having the shorter wave length.

Abstract: A method of identifying the presence, and amount, of elemental constituents in a material. The method uses an apparatus known for use in measuring extended x-ray absorption fine structure, and adapts it to the measurement of x-ray appearance potential in a manner to yield both qualitative and quantitative information about the elemental constituents of the material. The source of x-rays can be a synchrotron, which, because of its high power output, increases the speed and sensitivity of the measurements, permitting the use of less sensitive x-ray detectors to yield statistically significant data.