Abstract: Techniques disclosed herein include systems and methods for identifying counterfeit gold jewelry and other counterfeit gold items. Techniques include determining—using a non-destructive mechanism—whether an item of interest (such as an article represented as true gold) is solid gold or a gold-plated object. Techniques include using an X-ray fluorescence (XRF) analyzer to differentiate true gold from gold plating. The XRF analyzer can distinguish between gold plating and bulk gold material by comparing a ratio of L-alpha and L-beta x-ray lines of gold. The analyzer measures a ratio of intensities of characteristic L-lines of gold using X-ray fluorescence (XRF) spectroscopy. When implemented using an XRF analyzer, the system nondestructively determines whether a test object is made of solid gold/gold alloy or has gold plating only.

Abstract: Techniques disclosed herein include systems and methods for identifying counterfeit gold jewelry and other counterfeit gold items. Techniques include determining—using a non-destructive mechanism—whether an item of interest (such as an article represented as true gold) is solid gold or a gold-plated object. Techniques include using an X-ray fluorescence (XRF) analyzer to differentiate true gold from gold plating. The XRF analyzer can distinguish between gold plating and bulk gold material by comparing a ratio of L-alpha and L-beta x-ray lines of gold. The analyzer measures a ratio of intensities of characteristic L-lines of gold using X-ray fluorescence (XRF) spectroscopy. When implemented using an XRF analyzer, the system nondestructively determines whether a test object is made of solid gold/gold alloy or has gold plating only.

Abstract: An optical emission spectroscopic system contains multiple distinct light paths that provide increased light to a spectrometer, thereby increasing sensitivity and signal-to-noise of the system.

Abstract: A method is provided for screening lead concentration compliance of objects, particularly consumer products such as toys, using x-ray fluorescence (XRF) analysis. The measured intensity ratio of the characteristic L? and L? x-rays of lead provides an indication of whether the lead is located primarily in a coating (e.g., paint) layer on the object, or in a thin or thick bulk material. If the intensity ratio indicates that the lead is located in a coating layer or distributed in a thin bulk material, an areal density of lead is determined from at least one of the characteristic x-ray intensities, and the measured areal density is compared to specified lower and upper limits to determine whether the object is unambiguously compliant, unambiguously non-compliant, or indeterminate.

Abstract: Time-resolved analysis of a spectrum is performed by illuminating a one-dimensional array of charge-transfer device light-sensitive pixel cells and periodically non-destructively copying charges in the light-sensitive cells to respective storage cells (“row storage registers”) co-located with the light-sensitive cells in an integrated circuit. Information about the charges stored in at least some of the storage cells is provided to a component external to the integrated circuit.

Abstract: A method, instrument, and computer program software product for characterizing a sample with respect to the presence of a specified element, either as a constituent of a surface layer or of the bulk of the sample. Intensities of fluorescent emission at two characteristic emission lines are compared to establish whether the specified element is disposed above the bulk of the sample. In the case where the specified element is disposed above the bulk of the sample, an areal density of the specified element is determined, whereas in the case where the specified element is disposed within the bulk of the sample, a volumetric concentration of the specified element within the sample is determined.

Abstract: A hand-held, self-contained x-ray fluorescence (XRF) analyzer produces a small x-ray spot on a sample to interrogate the elemental composition of a sample region of millimeter-size characteristic dimension. The analyzer includes a collimator for aiming an x-ray beam toward a desired location on the sample and for determining the size of the spot produced on the sample. The analyzer may include a digital camera oriented toward the portion of the sample that is, or would be, interrogated by the x-ray spot to facilitate aiming the analyzer. The analyzer may generate a reticule in a displayed image to indicate the portion of the sample that is, or would be, illuminated by the x-ray beam. The analyzer may automatically annotate the image of the sample with text or graphics that contain information about the analyzed sample. The image may be stored in the hand -held analyzer or provided for external storage or display.

Abstract: A method for classifying a sample based upon a complete spectral analysis. The sample is illuminated with penetrating radiation and an initial complete spectral analysis is performed based on spectral resolution of resonant fluorescence lines emitted at the surface, or within the volume, of the sample. If the initial complete spectral analysis yields the composition of the sample to within acceptable limits, analysis values are output to the user. Otherwise, further analysis, informed by the results if the initial complete spectral analysis, is performed.

Abstract: An analytical instrument may be docked in a stand. The stand provides electrical power, cooling, gas to purge air from an analytical gap within the instrument and/or other supplies or services to the instrument. The stand contains a contactless memory, such as an RF-ID tag, which stores information about the supplies and/or services the stand is capable of providing to the instrument. The instrument reads the stand's contactless memory and automatically sets operational parameters of the instrument in accordance with the supplies and/or services the stand is capable of providing. Thus, the instrument may automatically operate in an enhanced mode, such as at a higher x-ray beam power, as a result of being mounted in the stand.

Abstract: Multiple energy sources, such as a laser and electrical current, are employed, in close coordination, spatially and temporally, to clean a sample, vaporize its material and excite vapor atoms for the purpose of atomic emission spectroscopy. These methods permit better monitoring and control of the individual processes in real time, lead to higher consistency and higher quality optical emission spectra, and enhance the measurements of non-conducting solids, liquids and gases. Additionally, a portable instrument is provided with both laser source and spectrometer optically coupled to a hand-holdable unit.

Abstract: Methods for in vivo measurement of lead or other trace elements in bone by x-ray fluorescence (XRF) without independent measurement of underlying tissue thickness are disclosed. In one method, the lead concentration is calculated based on the intensity of a first characteristic fluoresced peak and a function having as an argument the intensity ratio of first and second characteristic fluoresced peaks, with at least one parameter of the function being empirically determined by measurements of calibration phantoms having differing thicknesses of tissue surrogate material. In another method, the lead concentration is measured by estimating tissue thickness based on the intensity of the Compton scattering peak, or ratio of Compton/Rayleigh intensities, and the intensity of a characteristic fluoresced x-ray peak corrected for attenuation by tissue of the estimated thickness. Also disclosed is a method for determining the calcium concentration and density of bone based on XRF spectrum data.

Abstract: A method, instrument, and computer program software product for characterizing a sample with respect to the presence of a specified element, either as a constituent of a surface layer or of the bulk of the sample. Intensities of fluorescent emission at two characteristic emission lines are compared to establish whether the specified element is disposed above the bulk of the sample. In the case where the specified element is disposed above the bulk of the sample, an areal density of the specified element is determined, whereas in the case where the specified element is disposed within the bulk of the sample, a volumetric concentration of the specified element within the sample is determined.

Abstract: An instrument and method for measuring the elemental composition of a test material. The instrument has a source of penetrating radiation for irradiating an irradiated region of the test material, a detector for detecting fluorescence emission by the test material and for generating a detector signal, and a controller for converting the detector signal into a spectrum characterizing the composition of the test material. A platen of attenuating material extends outward from adjacent to, and surrounding, the irradiated surface of the test material. In certain embodiments, the thickness of the attenuating platen is tapered such as to decrease with increasing radial distance from the central irradiated region of the test material.

Abstract: An x-ray source produces a well-defined electron beam, without an undesirable halo. The x-ray source includes a housing, a cathode disposed within the housing, an anode spaced apart from the cathode for accelerating electrons emitted from the cathode and an x-ray emitter target disposed within the housing and spaced apart from the cathode for impact by the accelerated electrons. The cathode includes a passivation layer over only a portion of the area of the cathode, leaving an emission portion of the cathode that is not passivated. The passivation layer reduces or prevents emissions from the passivated portion of the cathode, thereby preventing a halo, which would otherwise be produced by lower-level emissions from the portion of the cathode that surrounds the emission portion of the cathode.

Abstract: A method for obtaining a concentrated, monochromatic x-ray beam from a standard x-ray tube or other source of polychromatic emission. X-rays from the anode of the x-ray tube fluoresce an adjoining, independent target that produces a monochromatic spectrum, a portion of which is focused by the x-ray optical system. This two-stage method gives the system considerably versatility without undue loss in signal. The two-stage concentrator makes practical the use of focusing optics in hand-held and portable instruments.

Abstract: An apparatus for inspecting objects utilizes a fan beam or flood beam to illuminate the inspected region of the object. A modulator, which may take the form of a movable mask, dynamically encodes the beam so that each segment of the inspected region receives varying amounts of radiation according to a predetermined temporal sequence. The resultant signal produced by a backscatter detector or optional transmission detector receiving radiation from the object is decoded to recover spatial information so that an image of the inspected region may be constructed.

Abstract: An apparatus for selective radiation detection includes a neutron detector that facilitates detection of neutron emitters, e.g. plutonium, and the like; a gamma ray detector that facilitates detection of gamma ray sources, e.g., uranium, and the like. The apparatus comprises a first light guide, optically coupled to a first optical detector; a second light guide, optically coupled to a second optical detector a sheet of neutron scintillator, opaque for incoming optical photons, said sheet of neutron scintillator sandwiched between the first and the second light guides. The second light guide comprises a gamma ray scintillator material.

Abstract: A spectrometer includes a structural member made of a light-weight material having a small coefficient of thermal expansion (CTE). The spectrometer is dimensionally stable over a range of expected ambient temperatures, without controlling the temperature of the spectrometer.

Abstract: Time-resolved analysis of a spectrum is performed by illuminating a one-dimensional array of charge-transfer device light-sensitive pixel cells and periodically non-destructively copying charges in the light-sensitive cells to respective storage cells (“row storage registers”) co-located with the light-sensitive cells in an integrated circuit. Information about the charges stored in at least some of the storage cells is provided to a component external to the integrated circuit.

Abstract: A hand-held, self-contained, battery-powered test instrument for analyzing composition of a sample includes an exciter for exciting at least a portion of the sample, a compact cross-dispersed spectrometer for receiving an optical signal from the excited portion of the sample and a processor for processing spectral data about the optical signal from the spectrometer. The exciter may include a spark generator and a counter electrode, a laser or other device for generating the optical signal from the sample portion. The spectrometer has a wavelength range broad enough to enable the test instrument to detect and determine relative quantities of carbon, phosphorous, sulfur, manganese, silicon, iron and other elements necessary to identify common alloys. The spectrometer includes a structural member made of a light-weight material having a small coefficient of thermal expansion (CTE).