【英文标准名称】:StandardPracticeforGoniometricOpticalScatterMeasurements
【原文标准名称】:测角光学散射测量的标准实施规程
【标准号】:ASTME2387-2005
【标准状态】:现行
【国别】:
【发布日期】:2005
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:E12.03
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:测量仪器;光学仪器;计量学;光学测量
【英文主题词】:bidirectionalreflectancedistributionfunction(BRDF);bidirectionalscatterdistributionfunction(BSDF);bidirectionaltransmittancedistributionfunction(BTDF);diffuse;irradiance;radiance;scatter;specular
【摘要】:Theangulardistributionofscatterisapropertyofsurfacesthatmayhavedirectconsequencesonanintermediateorfinalapplicationofthatsurface.Scatterdefinesmanyvisualappearanceattributesofmaterials,andspecificationofthedistributionandwavelengthdependenceiscriticaltothemarketabilityofconsumerproducts,suchasautomobiles,cosmetics,andelectronics.Opticallydiffusivematerialsareusedininformationdisplayapplicationstospreadlightfromdisplayelementstotheviewer,andtheperformanceofsuchdisplaysreliesonspecificationofthedistributionofscatter.Stray-lightreductionelements,suchasbafflesandwalls,relyonabsorbingcoatingsthathavelowdiffusereflectances.Scatterfrommirrors,lenses,filters,windows,andothercomponentscanlimitresolutionandcontrastinopticalsystems,suchastelescopes,ringlasergyros,andmicroscopes.Themicrostructureassociatedwithamaterialaffectstheangulardistributionofscatter,andspecificpropertiescanoftenbeinferredfrommeasurementsofthatscatter.Forexample,roughness,materialinhomogeneity,andparticlesonsmoothsurfacescontributetoopticalscatter,andopticalscattercanbeusedtodetectthepresenceofsuchdefects.Theangulardistributionofscatteredlightcanbeusedtosimulateorrendertheappearanceofmaterials.Qualityofrenderingreliesheavilyuponaccuratemeasurementofthelightscatteringpropertiesofthematerialsbeingrendered.p>1.1Thispracticedescribesproceduresfordeterminingtheamountandangulardistributionofopticalscatterfromasurface.Inparticularitfocusesonmeasurementofthebidirectionalscatteringdistributionfunction(BSDF).BSDFisaconvenientandwellacceptedmeansofexpressingopticalscatterlevelsformanypurposes.Itisoftenreferredtoasthebidirectionalreflectancedistributionfunction(BRDF)whenconsideringreflectivescatterorthebidirectionaltransmittancedistributionfunction(BTDF)whenconsideringtransmissivescatter.1.2TheBSDFisafundamentaldescriptionoftheappearanceofasample,andmanyotherappearanceattributes(suchasgloss,haze,andcolor)canberepresentedintermsofintegralsoftheBSDFoverspecificgeometricandspectralconditions.1.3Thispracticealsopresentsalternativewaysofpresentingangle-resolvedopticalscatterresults,includingdirectionalreflectancefactor,directionaltransmittancefactor,anddifferentialscatteringfunction.1.4ThispracticeappliestoBSDFmeasurementsonopaque,translucent,ortransparentsamples.1.5Thewavelengthsforwhichthispracticeappliesincludetheultraviolet,visible,andinfraredregions.Difficultyinobtainingappropriatesources,detectors,andlowscatteropticscomplicatesitspracticalapplicationatwavelengthslessthanabout0.2m(200nm).Diffractioneffectsstarttobecomeimportantforwavelengthsgreaterthan15m(15000nm),whichcomplicateitspracticalapplicationatlongerwavelengths.Measurementspertainingtovisualappearancearerestrictedtothevisiblewavelengthregion.1.6Thispracticedoesnotapplytomaterialsexhibitingsignificantfluorescence.1.7Thispracticeappliestoflatorcurvedsamplesofarbitraryshape.However,onlyaflatsampleisaddressedinthediscussionandexamples.Itistheusersresponsibilitytodefineanappropriatesamplecoordinatesystemtospecifythemeasurementlocationonthesamplesurfaceandappropriatebeampropertiesforsamplesthatarenotflat.1.8ThispracticedoesnotprovideamethodforascribingthemeasuredBSDFtoanyscatteringmechanismorsource.1.9Thispracticedoesnotprovideamethodtoextrapolatedatafromonewavelength,scatteringgeometry,samplelocation,orpolarizationtoanyotherwavelength,scatteringgeometry,samplelocation,or......
【中国标准分类号】:A60
【国际标准分类号】:17_180_30
【页数】:14P.;A4
【正文语种】: