1、BRITISH STANDARD BS EN 14096-1:2003 Non-destructive testing Qualification of radiographic film digitisation systems Part 1: Definitions, quantitative measurements of image quality parameters, standard reference film and qualitative control The European Standard EN 14096-1:2003 has the status of a Br
2、itish Standard ICS 01.040.19; 01.040.37; 19.100; 37.040.25 BSEN 14096-1:2003 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 7 May 2003 BSI 7 May 2003 ISBN 0 580 41787 5 National foreword This British Standard is the official English language
3、 version of EN 14096-1:2003. The UK participation in its preparation was entrusted to Technical Committee Wee/46, Non-destructive testing, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British
4、Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online.
5、 This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible
6、international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the
7、 EN title page, pages 2 to 14, an inside back cover and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN140961 April2003 ICS01.040.1
8、9;01.040.37;19.100;37.040.25 Englishversion NondestructivetestingQualificationofradiographicfilm digitisationsystemsPart1:Definitions,quantitative measurementsofimagequalityparameters,standardreference filmandqualitativecontrol EssaisnondestructifsQualificationdessystmesde numrisationdesfilmsradiogr
9、aphiquesPartie1: Dfinitions,mesuresquantitativesdesparamtresde qualitdimage,filmderfrencenormalisetcontrle qualitatif ZerstrungsfreiePrfungQualifizierungvonRntgenfilm DigitalisierungssystemenTeil1:Definitionen,quantitative MessungvonBildqualittsparametern,Standard ReferenzfilmundQualittssicherung Th
10、isEuropeanStandardwasapprovedbyCENon11March2003. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeob
11、tainedonapplicationtotheManagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandnotifiedtotheManagementCentrehasthesamestatusasthe official versions.
12、 CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Slovakia,Spain,Sweden,SwitzerlandandUn ited Kingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATI
13、ON EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2003CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.EN140961:2003EEN140961:2003(E) 2 Contents page Foreword3 1 Scope 4 2 Normativereferences 4 3 Termsanddefinitions. .4 4 Ev
14、aluationprocedures . .7 5 Standardreferencefilm. 11 6 Qualitativecontrolandlongtermstabilityofthedigitisationsystem .13EN140961:2003(E) 3 Foreword Thisdocument(EN140961:2003)hasbeenpreparedbyTechnicalCommitteeCEN/TC138,“Nondestructive testing“,thesecretariatofwhichisheldbyAFNOR. ThisEuropeanStandard
15、shallbegiventhestatusofanationalstandard,eitherbypublicationofanidenticaltextor byendorsement,atthelatestbyOctober2003,andconflictingnationalstandardsshallbewithdrawnatthelatest byOctober2003. EN14096comprisesaseriesofEuropeanStandardsforradiographicfilmdigitisationsystemswhichismadeupof thefollowin
16、g: EN140961 Nondestructive testing Qualification of radiographic film digitisation systems Part 1: Definitions,quantitativemeasurementsofimagequalityparameters,standardreferencefilmand qualitativecontrol EN140962 NondestructivetestingQualificationofradiographicfilmdigitisationsystemsPart2:Minimum re
17、quirements AccordingtotheCEN/CENELECInternalRegulations,thenationalstandardsorganizationsofthefollowing countriesareboundtoimplementthisEuropeanStandard:Austria,Belgium,CzechRepublic,Denmark,Finland, France,Germany,Greece,Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal, Sl
18、ovakia,Spain,Sweden,SwitzerlandandtheUnitedKingdom.EN140961:2003(E) 4 Introduction RadiographicfilmsystemsareusedforindustrialinspectionbyXandgammarays.Toapplymodernmeansof computersupportforanalysis,transmissionandstoragetheinformationstoredintheradiographicfilmshouldbe convertedintodigitaldata(dig
19、itisation).ThisEuropeanStandarddefinesminimumrequirementstoensurethatthe relevantinformationforevaluationofthedigitaldataispreservedduringthefilmdigitisationprocess. 1Scope ThisEuropeanStandardspecifiesproceduresfortheevaluationofbasicperformanceparametersofthe radiographicfilmdigitisationprocesssuc
20、hasspatialresolutionandspatiallinearity,densityrange,densitycontrast sensitivityandcharacteristictransfercurve.Theycanbeintegratedintothesystemsoftwareandtogetherwitha standardreferencefilm(asdescribedinclause5)usedforqualitycontrolofthedigitisationprocess.Thisreference filmprovidesaseriesoftesttarg
21、etsforperformanceevaluation.Thetesttargetsaresuitableforevaluatinga digitisationsystemwithaspatialresolutiondownto25m,adensitycontrastsensitivitydownto0,02optical density,adensityrangeof0,5to4,5andafilmsizecapacityof(350x430)mm.Thisstandarddoesnotaddress signalprocessinganddisplayofthedigitiseddata.
22、 2 Normativereferences ThisEuropeanStandardincorporatesbydatedorundatedreference,provisionsfromotherpublications.These normativereferencesarecitedattheappropriateplacesinthetext,andthepublicationsarelistedhereafter.For datedreferences,subsequentamendmentstoorrevisionsofanyofthesepublicationsapplytot
23、hisEuropean Standardonlywhenincorporatedinitbyamendmentorrevision.Forundatedreferencesthelatesteditionofthe publicationreferredtoapplies(includingamendments). EN5841,Nondestructivetesting Industrialradiographicfilm Part 1:Classificationoffilmsystemsfor industrialradiography. EN140962, Nondestructive
24、testingQualificationofradiographicfilmdigitisationsystemsPart2:Minimum requirements. 3 Termsanddefinitions ForthepurposesofthisEuropeanStandard,thefollowingtermsanddefinitionsapply. 3.1 radiographicfilmdigitisationsystem digitiser sequentialapplicationofthetwofunctionsbelow: a) detectionofthediffuse
25、transmittanceofasmallunitareaofthefilm(pixel,pictureelement)bymeansofan opticaldetector,givinganelectricoutputsignal(geometricaldigitisation); b) conversionoftheaboveelectricalsignalintoanumericalvalue(densitometricaldigitisation) 3.2 scanningaperture S A spatialextension(area)ontheradiographicfilmt
26、hroughwhichthedigitiserperformsthescanningofonepixelfor geometricaldigitisation Thesizeofthescanningaperturecorresponds:EN140961:2003(E) 5 inthecaseofrectangularaperture:tothelongerside, inthecaseofcircularaperture:tothediameter. Thescanningaperturelimitsthespatialresolutionofthedigitiser. 3.3 pixel
27、size P geometricalcentretocentredistancebetweenadjacentpixelsinarow(horizontalpitch)orcolumn(verticalpitch) ofthescannedimage 3.4 opticaldensity D logarithmicvaluetothebase10ofthediffuselightintensityratioinfrontof( I 0 )andbehind( I D )theradiographicfilm accordingtoequation(1): D I I D 0 lg (1) 3.
28、5 edgespreadfunction ESF resultingprofileacrossastepfunctionafterdigitisation NOTE Thisfunctioncanbeeitheraslightintensityoropticaldensity. 3.6 digitiserunsharpness U D blurringofsharpedgesbythescanningaperture,scatteredlight,flareorelectronicbandwidth Itisdeterminedfromthegeometricaldistanceofthe10
29、%and90%pointoftheEdgeSpreadFunction(ESF)froma lightintensitystepfunction. 3.7 spatialfrequency f describedbyasinusoidalintensityvariationalongageometricalaxis Theperiodofthisfunctionismeasuredinnumberoflinepairspermillimetre(lp/mm). 3.8 spatialfrequencymaximumvalue f c intheory,thisvalue,innumberofl
30、inepairspermillimetre,isgivenbytheNyquistsamplingtheorem,seeequation (2): ) * 2 ( / 1 P f c (2) Practically,thescanningaperture,themechanicsandtheelectronicsofthedigitiserreducethistheoreticalvalue. 3.9 modulationtransferfunction MTF normalisedmagnitudeoftheFouriertransform(FT)ofthedifferentiatedspa
31、tialopticaldensityedgespread function(ESF)(seeFigure1) Itdescribestheunsharpnessfunctionofthedigitiser(contrasttransmissionasafunctionoftheobjectsize).EN140961:2003(E) 6 NOTE ThisMTFcalculationisbasedonopticaldensities,whichcorrespondtotheXraydose. 3.10 densityrange D R rangeofmaximumandminimumoptic
32、aldensities,whichcanbemeasuredbythedigitiser Dependingontheconstructionofthedigitiser,thisdensityrangecanbesplitintoseveralworkingranges(e.g.bya differentilluminationpowerand/oradifferentdetectorintegrationtime). 3.11 characteristictransfercurve CTC relationshipbetweentheopticaldensityofthefilmandth
33、edigitiseddata 3.12 digitalresolution inbit numberofbitsprovidedbytheanaloguetodigitalconverterofthedigitiserusedfordensitometricaldigitisation NOTE AdigitalresolutionofNbitscorrespondsto2 N digitalvalues. 3.13 densitysamplingpitch D SP opticaldensityvariationcorrespondingtoanincreaseof1inthedigitis
34、edvalue NOTE Thisdensityvariationdependsonthecharacteristictransfercurveofthedigitiser.Thedensitysamplingpitchcanbe afunctionofthedensity. 3.14 densitycontrastsensitivity D CS minimumdensityvariationofthefilm,whichisresolvedbythedigitiser Thisismostlydeterminedbythedigitisationnoiseofthedigitiser(qu
35、antumnoiseofthelightdetector). 3.15 workingrange D WR rangeofopticaldensities,wherethedigitiserguaranteesaminimumdensitycontrastsensitivityinonesingle acquisition Onlyinthisdensityrangethedigitiseddatacanbeusedforevaluation.Dependingonthedigitiserconstruction therecanbemorethanoneworkingrange,e.g.fo
36、rbrighterordarkerfilms. 3.16 singleacquisition digitisationofoneradiographicfilmperformedwithonesinglescan Theresultofwhichisacollectionofdatanotsubjecttoanytypeoffurtherprocessing.Auniquesetofparameters ofthedigitisationsystemisusedforthisacquisition. 3.17 standardreferencefilm photographicimageona
37、nindustrialradiographicfilmcontainingallofthereferencetargetsdescribedinthis document 3.18 targets physicalpatternsonthestandardreferencefilmwhichareusedtoevaluatethedigitiserEN140961:2003(E) 7 4Evaluation procedures 4.1Evaluationofthecharacteristictransfercurve,densityrange,pixelsizeanddensitycontr
38、ast sensitivity 4.1.1 Steppeddensitytarget Forthemeasurementofthecharacteristictransfercurve,thedensityrangeandthedensitycontrastsensitivityof thedigitiserasteppeddensitytargetonareferenceradiograph(standardreferencefilm)isrequiredwiththe followingrequirements: tocovertheopticaldensityintervalbetwee
39、n D=0,5and D=4,5; theopticaldensityspacingbetween2adjacentstepsisnotgreaterthan D=0,5; theareaofeachstepisatleast100mm; afinegraintypefilm(systemclassC1inEN5841)withlightexposureshallbeusedtoachieveafine granularityresultingintoafilmnoiselessthan D=0,01(at88,6mpixelsize). 4.1.2 Characteristictransfe
40、rcurve(CTC) Forauniquesetofdigitiserparameters,anacquisitionofthesteppeddensitytargetonthereferencefilmis performed.Foreachdensitystep D i thearithmeticmeanvalue i gl ofthedigitiseddatavalues gl j,i foranareaof (15x15)pixelshallbedeterminedaccordingtoequation(3): 225 1 j i j, i 225 1 gl gl (3) Thech
41、aracteristictransfercurveofthedigitiserisconstructedfromthetableof D i versus i gl . Missingdensityvaluesbetweenthemeasureddensitystepscanbeinterpolatedincompliancewiththefollowing conditions: forlinearsystems(digitaldataproportionaltolightintensity)thecurveshallbelogarithmic, forlogarithmicsystems(
42、digitaldataproportionaltoopticalfilmdensity,providedbyelectroniclogamplifiersor digitalLUT)thecurveshallbelinear. Thedigitaldataprovidedbythedigitiserandthecorrespondingopticaldensityvaluesshallbereportedinatable and/oradiagram. Thediscretedensityvaluesexpressedbythedigitaldatashallbenamed D(gl). De
43、pendingontheconstructionofthedigitiser,theCTCcanbedifferentforthesteppeddensitytargetinscanning directionandperpendiculartoit. 4.1.3 Densityrange( D R ) Thedensityrangeofthedigitiserisdeterminedbythecharacteristictransfercurve.Itisthedifferencebetweenthe minimumandmaximumopticaldensity,whichcanberesolvedbythedigitiser.Theminimumandmaximumoptical densityforagivenparametersetofthedigitisercanbefoundfromthecorrespondingcharacteristictransfercurve. ButtherecanbedigitiserparameterswhichselectadifferentCTC.Thenthedensityrangeiscalculatedf
