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High Definition X-Ray Fluorescence (HDXRF) XOS Introduces HDXRF for Rapid Detectionof Lead in Toys & Consumer Products

i!h efinition X-Ray Fluorescence ( XRF), the ne"t !eneration technique for lead detection,assists manufacturers and re!ulators with this important pu lic health issue. XRF provides anunprecedented com ination of rapid results and pinpoint accuracy.

BENEFITS OF HDXRFRa i! results

Faster measurement speed ena les the inspection of a lar!er num er of toys* more than +times faster compared to conventional analytical techniques.

"ccuracy XRF has e"tremely low limits of detection yieldin! truly relia le results, dramatically

reducin! the num er of false positives or ne!atives.S#all S ot

ook at small features with spot si'e of + mm diameter with no reduction in speed or dataquality.

Easy to use XRF analy'ers have a very lar!e sample cham er, require little to no sample preparation,

and can measure virtually any type of product.

Non-!estructi$e

%fter testin!, products can e returned to the production line, store shelf, or consumer.%ersatile

XRF can accept products ran!in! in si'e from a !rain of sand to somethin! as lar!e as aschool us.

Outsi!e the la& #his versatile system is appropriate for manufacturin! facilities, distri ution centers and retail

outlets from the point of ori!in to the end user.

'H"T IS HDXRFXRF is an elemental analysis technique which uses Doubly urved rystal (D ) optics to

enhance measurement intensities y capturin! X-rays from a diver!ent source and redirectin! them intoan intense focused eam on the surface of the product. #he dia!ram elow shows the asicconfi!uration of XRF used to provide lead measurement in consumer products.

http://www.xos.com/materials-analysis/x-ray-optics-excitation-systems-x-beam/optics/doubly-curved-crystals/http://www.xos.com/materials-analysis/x-ray-optics-excitation-systems-x-beam/optics/doubly-curved-crystals/http://www.xos.com/materials-analysis/x-ray-optics-excitation-systems-x-beam/optics/doubly-curved-crystals/http://www.xos.com/materials-analysis/x-ray-optics-excitation-systems-x-beam/optics/doubly-curved-crystals/

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XRF usin! optics for to"ic metals measurement of consumer products.

#he ma/or enefit of XRF is that monochromatic e"citation eliminates the X-ray scatterin! ack!round under the fluorescence peaks, !reatly enhancin! detection performance. #his newanalytical approach results in detection limits in the parts-per- illion (pp ) ran!e for many elements ofinterest in a variety of materials. 0elow is a comparison at one-second measurement time for lead in atoy.

%ctual plastic toy measurements taken with conventional XRF (left) and HDXRF (ri!ht). 1otice thelead peaks (2 ) are arely visi le in the conventional XRF ut XRF eliminates the ack!roundinterference so lead levels are determined instantly.

Energy Dis ersi$e X-ray Fluorescence (EDXRF)3ner!y ispersive X-ray Fluorescence (3 XRF) is one of two !eneral types of X-ray Fluorescencetechniques used for elemental analysis applications. In 3 XRF spectrometers, all of the elements in thesample are e"cited simultaneously, and an ener!y dispersive detector in com ination with a multi-

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channel analy'er is used to simultaneously collect the fluorescence radiation emitted from the sampleand then separate the different ener!ies of the characteristic radiation from each of the different sampleelements. Resolution of 3 XRF systems is dependent upon the detector, and typically ran!es from +4e5 6 7 e5. #he principal advanta!es of 3 XRF systems are their simplicity, fast operation, lack ofmovin! parts, and hi!h source efficiency.

X-ray optics can e used to enhance 3 XRF instrumentation. For conventional XRF instrumentation,

typical focal spot si'es at the sample surface ran!e in diameter from several hundred micrometers up toseveral millimeters. Polycapillary focusing optics collect X-rays from the diver!ent X-ray source anddirect them to a small focused eam at the sample surface with diameters as small as tens ofmicrometers. #he resultin! increased intensity delivered to the sample in a small focal spot allows forenhanced spatial resolution for small feature analysis and enhanced performance for measurement oftrace elements for Micro EDXRF applications.

Doubly curved crystal optics direct an intense micron-si'ed monochromatic X-ray eam to the sample

surface for enhanced elemental analysis.

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%dditionally, two doubly curved crystal optics can e used for !onochro!atic WDXRF with theadvanta!e of very hi!h sensitivity for a specific sample element of interest. #he technolo!y has eensuccessfully used for measurement of low levels of sulfur in petroleum availa le in the X"# #$%D$Eanaly&er .

icro X-ray Fluorescence (*XRF):icro X-ray fluorescence (;XRF) is an elemental analysis technique which allows for the e"aminationof very small sample areas. ike conventional XRF instrumentation, :icro X-ray Fluorescence usesdirect X-ray e"citation to induce characteristic X-ray fluorescence emission from the sample forelemental analysis.

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optics overcome the limitation of inverse square dependence of X-ray intensity on distance from thesource, ena lin! the development of small si'e and low power ;XRF systems for in-line semi-conductor and other materials- ased industries and development of remote or porta le instruments.;XRF with X-ray optics have een successfully used for applications includin! small featureevaluation, elemental mappin!, film and platin! thickness measurement, detection of micro-contamination, evaluation of multi-layered coatin!s for advanced circuit oards, small particle analysis,

and forensics. Polycapillary focusing optics collect X-rays from the diver!ent X-ray source and direct them to a smallfocused eam at the sample surface with diameters as small as tens of micrometers. #he resultin!increased intensity delivered to the sample in a small focal spot allows for enhanced spatial resolutionfor small feature analysis and enhanced performance for measurement of trace elements over thatachieved with simple pinhole collimators.

Doubly curved crystal optics direct an intense micron-si'ed monochromatic X-ray eam to the samplesurface for enhanced elemental analysis. :onochromatic e"citation eliminates the X-ray scatterin!

ack!round under the fluorescence peaks and therefore !ives improved measurement sensitivity over;XRF methods usin! a pinhole.

;XRF can e achieved usin! polycapillary or dou ly curved crystal optics usin! 3 XRF or $ XRF!eometries.

8tandard ;XRF confi!uration. #he sample can e scanned to measure the elemental distri ution withina sample with a spatial resolution as small as + ;m (ener!y dependent).

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:icro $ XRF instrumentation usin! a polycapillary focusin! optic to focus X-rays from the source tothe sample and a polycapillary collimatin! optic to collect fluorescence emission from a small spot on

the sample surface and direct it to the dispersion crystal.

:icro $ XRF usin! a polycapillary focusin! optic to focus X-rays from the source to the sample anda dou ly curved crystal monochrometer to collect and disperse fluorescence X-rays from a small spot

on the sample and direct them to the detector.

onfocal ;XRF uses two polycapillary optics, one for small spot sample e"citation and a second to actas a spatial filter for all applications were ack!round radiation from areas not in the re!ion of interest

interferes with the si!nal of interest. #his confi!uration is useful for measurement of spatialdistri utions in radioactive samples as well as depth profilin! applications.

:onochromatic :icro 3 XRF usin! ou ly urved rystal =ptics.

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:onochromatic $ XRF usin! dou ly curved crystal optics has the advanta!e of very hi!h sensitivityfor a specific sample element of interest. #his technique has een successfully used for measurement of

low levels of sulfur in petroleum products.

onochro#atic icro X-ray Fluorescence( *XRF):icro X-ray fluorescence (;XRF) is an elemental analysis technique which allows for the e"aminationof very small sample areas (typically + s to + s of micrometers in diameter). X-ray optics can e usedto enhance ;XRF applications y capturin! X-rays from a diver!ent source over a lar!e an!le and toredirect them to an intense, focused eam on the sample surface. :onochromatic ;XRF (or :;XRF)is facilitated y doubly curved crystal optics , which direct an intense micron-si'ed monochromatic X-ray eam to the sample surface for enhanced elemental analysis. :;XRF provides several advanta!esover ;XRF techniques usin! polychromatic e"citation for some applications, includin! lar!er workin!distances and simpler quantitative analysis. :ore importantly, monochromatic e"citation eliminates theX-ray scatterin! ack!round under the fluorescence peaks and therefore !ives very hi!h sensitivity.#ypical detection limits at pp levels for ulk contaminants or femto!ram levels can e achieved withthis technique.

:;XRF can e achieved usin! optics for oth 3 XRF and $ XRF !eometries.

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:onochromatic $ XRF usin! dou ly curved crystal optics has the advanta!e of very hi!h sensitivityfor a specific sample element of interest. #his technique has een successfully used for measurement of

low levels of sulfur in petroleum products.

onochro#atic 'a$elength Dis ersi$e X-rayFluorescence ( 'D XRF)ou ly curved crystals can e used to enhance conventional wavelen!th dispersive XRFinstrumentation. #hese diffraction- ased optics ena le hi!hly intense monochromatic X-ray eamsusin! low-power, air-cooled X-ray tu es. #hese three dimensionally shaped optics selectively reflect avery narrow and of X-ray wavelen!ths for sample e"citation, accordin! to 0ra!! diffraction laws.

% monochromatic wavelen!th dispersive X-ray fluorescence (:$ XRF) analy'er uses two dou lycurved crystal optics. #ypical instrumentation includes a low-power X-ray tu e, a point-to-point

focusin! optic for e"citation, a sample cell, a second focusin! optic for fluorescence collection, and anX-ray detector. #he first focusin! optic captures a narrow andwidth of X-rays from the source andfocuses this intense monochromatic eam to a small spot on the sample. #he monochromatic primary

eam e"cites the sample and secondary characteristic fluorescence X-rays are emitted. #he second collection optic collects only select characteristic X-ray wavelen!ths of interest within a narrow

andwidth.

#his confi!uration offers several advanta!es over conventional $ XRF systems. #he si!nal-to- ack!round is improved y usin! the monochromatic e"citation of the X-ray source characteristic line.8econdly, the focusin! a ility of the collection optic allows usin! a small-area X-ray counter detector,which results in low detector noise and enhanced relia ility. :onochromatic e"citation also providessimplified quantitation and matri" effect correction. #his technique ena les ro ust, low maintenance,

online analy'ers with dramatically lower detection limits and faster response times.

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:onochromatic $ XRF usin! dou ly curved crystal optics has the advanta!e of very hi!h sensitivityfor a specific sample element of interest. #his technique has een successfully used for measurement of

low levels of sulfur in petroleum products.

Total Reflection X-ray Fluorescence (TXRF)#otal reflection X-ray fluorescence (#XRF) is a surface elemental analysis technique often used for theultra-trace analysis of particles, residues, and impurities on smooth surfaces. It is currently an importanttool for wafer surface contamination control in semiconductor chip manufacturin!.

#XRF is asically an ener!y dispersive XRF technique in a special !eometry. %n incident eamimpin!es upon a sample at an!les elow the critical an!le of e"ternal total reflection for X-raysresultin! in reflection of almost + ? of the e"citation eam photons. ue to its unique confi!uration,the main advanta!e of #XRF over conventional XRF is reduced measurement ack!round

contri utions y elimination of sample scatterin! resultin! in increased elemental measurementsensitivity.

a) onventional XRF !eometry. #he an!le of incidence is !reater than the critical an!le and the primary radiation penetrates into the sample.

) onventional #XRF !eometry. #he an!le of incident X-rays is less than the critical an!le and the primary radiation is reflected off of the sample surface.

=ne of the ma/or draw acks of conventional #XRF is that locali'ed sample information is difficult too tain due to the lar!e e"citation eam si'e (typically + cm in diameter). ou ly curved crystal opticscan e used to focus X-rays to small spots for locali'ed #XRF elemental analysis. % slit is used torestrict eam diver!ence in the scatterin! plane to less than the critical an!le in order to meet the total

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#he ma/or advanta!e offered y the electron e"citation, as opposed to X-ray e"citation, is the small pro e si'e, typically C + @m, and its hi!h e"citation efficiency, especially in the low-ener!y ran!e.owever, 32-XRF has some ma/or limitations. First, the electron source causes 0remsstrahlun!

ack!round which limits the sensitivity of 32XRF analysis. 8econdly, 32XRF is a surface-sensitivetechnique and cannot e used to measure underlayer materials in a sample. In contrast, XRF analysisusin! X-ray e"citation offers much hi!her detection sensitivity, especially for hi!h-ener!y X-rays.

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within the sample. 8amples must e run under hi!h vacuum conditions and must e conductive orcoated with a conductin! material such as !old for proper analysis. X-ray microanalysis of uncoatednon-conductive samples in the conventional 83: is hampered y specimen char!in! which can reducethe ener!y of the electron eam and make quantitative analysis impossi le. #he environmentalscannin! electron microscope (383:) is a unique instrument in which uncoated iolo!ical andindustrial materials can e e"amined with an electron eam in a hi!h cham er pressure atmosphere of

water vapor. #herefore, specimens can e analy'ed usin! 383: without destruction and additionalspecimen preparation procedures. ynamic e"periments are also possi le in the 383:, such as dryin!or crystalli'ation.

#he main disadvanta!e of typical 383: instrumentation is that the electron eam spreads in the hi!h- pressure environmental cham er and e"cites fluorescent X-rays from the entire specimen, not /ust fromunder the electron eam. #he fluorescent X-rays !enerated outside the area of interest are detected ythe detector and reduce the ima!e contrast.

% polycapillary optic can e incorporated into an e"istin! 383: to collect X-rays from an area defined y the optic input focal spot si'e and focus them on the detector, therefore reducin! the ack!round andenhancin! the ima!e contrast.

% polycapillary focusin! optic as a spatial filter in an 383:. #he XRF si!nal from a small re!ionwithin the spread of the electron eam can e selected with the focusin! optic.

Electron ,ro&e Energy Dis ersi$e S ectrosco y(EDS)3lectron-pro e X-ray fluorescence (32-XRF) analysis has een widely used in scannin! electronmicroscopy instrumentation for elemental analysis of specimens. In the 83:, the surface of a solidsample is e"cited with a hi!hly-focused ener!etic eam of electrons, which induces X-ray fluorescencefrom the elements within the sample.

2olycapillary focusin! optics can e used to focus emitted X-ray fluorescence from the small electrone"citation area onto the detector to increase the efficiency of collection of emitted X-ray fluorescence.#his !reatly increases the elemental discrimination and detection sensitivity. #his has een shown to eimportant for applications such as microcalorimetry.

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Electron ,ro&e 'a$elength Dis ersi$eS ectrosco y ('DS)3lectron-pro e X-ray fluorescence (32-XRF) analysis has een widely used in scannin! electronmicroscopy instrumentation for elemental analysis of specimens. In the 83:, the surface of a solidsample is e"cited with a hi!hly-focused ener!etic eam of electrons, which induces X-ray fluorescencefrom the elements within the sample.

2olycapillary collimatin! optics can e used to direct emitted X-ray fluorescence as a parallel eamfrom the small electron e"citation area to a flat crystal monochrometer to increase the diffracted eamintensity and therefore !reatly increase the elemental discrimination and detection sensitivity.