ASTM E3165-2018 Standard Test Method for Nighttime Retroreflected Chromaticity of Retroreflective Sheeting.pdf

1、Designation: E3165 18Standard Test Method forNighttime Retroreflected Chromaticity of RetroreflectiveSheeting1This standard is issued under the fixed designation E3165; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la

2、st revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method describes the instrumental determina-tion of the nighttime retroreflected chromaticity coordinates ofre

3、troreflective sheeting.1.2 This method includes a procedure based on tristimulusfilter colorimetery and a procedure based on spectral measure-ments.1.3 A single set of test geometries (using 0.33 observationangle and 5 entrance angle) and apertures are described in thismethod.1.4 The resulting chrom

4、aticity coordinates are for use withthe CIE 1931 chromaticity system utilizing CIE Illuminant A.1.5 If measurements and calculations are required for othersources of illumination, or geometries, or other materials, theuser is referred to the general practice described in PracticeE811.1.6 The values

5、stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.7 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety

6、, health, and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of In

7、ternational Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D4956 Specification for Retroreflective Sheeting for TrafficControlE284 Terminology of AppearanceE308 Practice for Computing

8、 the Colors of Objects by Usingthe CIE SystemE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE808 Practice for Describing RetroreflectionE809 Practice for Measuring Photometric Characteristics ofRetroreflectorsE810 Test Method for Coefficient of Retror

9、eflection ofRetroreflective Sheeting Utilizing the Coplanar GeometryE811 Practice for Measuring Colorimetric Characteristics ofRetroreflectors Under Nighttime Conditions2.2 CIE and ISO Documents:3CIE Publication 15:2004 ColorimetryCIE Technical Report 54.2 Retroreflection: Definition andMeasurementC

10、IE Technical Report 72 Guide to the Properties and Uses ofRetroreflectors at NightISO 116641:2007 (CIE S 0141/E:2006) ColorimetryPart 1: CIE Standard Colorimetric ObserversISO 116642:2007 (CE S 0142/E:2006) ColorimetryPart2: CIE Standard Illuminants2.3 U. S. Federal Regulations:4US Code of Federal R

11、egulations (CFR) Title 23: Highways:Part 655Traffic Operations, Subpart FTraffic Control1This test method is under the jurisdiction of ASTM Committee E12 on Colorand Appearance and is the direct responsibility of Subcommittee E12.10 onRetroreflection.Current edition approved July 1, 2018. Published

12、September 2018. DOI:10.1520/E3165-18.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from U.S. Nat

13、ional Committee of the CIE (International Commissionon Illumination), C/o Alan Laird Lewis, 282 E. Riding, Carlisle, MA 01741,http:/www.cie-usnc.org.4Available from U.S. Government Printing Office, Superintendent ofDocuments, 732 N. Capitol St., NW, Washington, DC 20401-0001, http:/www.access.gpo.go

14、v.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of Int

15、ernational Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1Devices on Federal-Aid and Other Streets and Highways3. Terminology3.1 The terms and definitions in Terminology E284 apply tothis test method.3.2 Definitions:3.2.1 chr

16、omaticity coordinates, nthe ratio of each of thetristimulus values of any viewed light to the sum of the three.3.2.1.1 DiscussionChromaticity coordinates in the CIE1931 system of color specification are designated by x, y, andz.3.2.2 spectral coeffcient of retroreflection RA(), ntheratio of the spec

17、tral coefficient of radiant intensity RI() of theretroreflector for a given geometrical configuration to the areaA of the retroreflector.RA! 5RI!A3.2.3 spectral coeffcient of retroreflected radiant intensityRI(), nthe ratio of the spectral radiant intensity Ie() of theretroreflector for a given geom

18、etrical configuration to thespectral irradiance Ee() of the incident light source at theretroreflector on a plane perpendicular to the illumination axis.RI! 5Ie!Ee!4. Summary of Test Method4.1 The general procedure is to illuminate the test specimenwith the specified source, in the prescribed geomet

19、ry, andanalyze the reflected light using the calculation in DIE Publi-cation 15.4.2 The geometric arrangement can be either a longer-distance photometric range or an optically-reduced equivalentgeometry for laboratory bench or field work.4.3 The measurements may be performed using a substitu-tion st

20、andard calibrated by an appropriate calibration labora-tory. Measurements are then relative to this standard.5. Significance and Use5.1 The results of this test method are used to assessconformance of retroreflective sheeting to the nighttime colorrequirements of industry standards and governmentreg

21、ulations, such as Specification D4956 and U.S. Code ofFederal Regulations Title 23 Part 655 Subpart F.5.2 Requirements in specifications referring to this testmethod are for the chromaticity of the material as viewed atnight. These requirements are generally stated using four orfive corner points th

22、at form a box that limits the range ofacceptable chromaticity. Most of these specifications are cat-egorical in nature; they describe a small range of colors that arerecognizable from a color naming or coding purpose5.3 The method for compliance with the specification is toplot the measured (x, y) v

23、alues and determine if the measuredpoint falls within the specification box for the color of interest.6. Apparatus6.1 The apparatus consists of a light source, a receptor(tristimulus or spectral) and the geometric arrangement (eitherin a photometric range or an optically-reduced design forlaboratory

24、 bench or field use).6.2 The light source shall closely approximate the spectraldistribution of CIE IlluminantA(a correlated color temperatureof 2856 K, see Practice E308).NOTE 1Non-fluorescent samples may be illuminated with non-Illuminant A (for example, broadband) light sources using this method.

25、The CIE Illuminant A light source is considered the referee condition forthis test method.6.3 The receptor shall closely approximate the CIE tristimu-lus functions when used. For spectral testing the dispersingelements shall provide a range from 380 to 740 nm witha5nmincrement anda5nmbandpass. (For

26、spectral measurementsmade by systems with increment and bandpass 5 nm, forexample, array detectors, integration techniques are acceptableto obtain the equivalent ofa5nmbandpass).NOTE 2Other bandpass specifications may be used. For example, theprecision and bias data contained in Section 12 were coll

27、ected byequipment having either 5 nm or 10 nm bandpass. The 5 nm bandpass isconsidered the referee condition for this test method.7. Sampling, Test Specimens, and Test Units7.1 Multiple samples shall be gathered from the retroreflec-tive sheeting material in a manner so as to constitute arepresentat

28、ive sampling. One example of a sampling procedureis described in Section 9 of Specification D4956. Deviationsfrom this procedure shall be described in the report.7.2 The reference test specimen in this procedure shall be200 6 100 mm by 200 6 100 mm in size. The entire specimento be measured shall be

29、 illuminated.NOTE 3The sample dimensions specified above refer to the refereelaboratory measurement. Field measurements may dictate other sampledimension requirements. In all cases, the minimum illuminated area shallbe a circle having a 25 mm diameter.7.3 Retroreflective sheeting materials may have

30、color char-acteristics that vary slowly with changes in observation,entrance, and orientation angle. Care should be taken to ensurecareful preparation of the sample and placement in the mea-surement system.7.4 Retroreflective sheeting may produce small “rainbowlike” diffraction effects at some obser

31、vation angles. If there isconcern that these effects are present, then the maximum fixedaperture size (10 min of arc; see 9.2) is to be used as the refereeconfiguration. In general, measurements at apertures less thanthe maximum size will provide no significant effect on theresults and may be used.7

32、.5 Measurement AnglesThis method uses the CIE goni-ometer system (, 1, 2, ). The angles used in the measure-ment are: observation angle = 20 min of arc (0.33), entranceangle 1= 5, entrance angle 2= 0, and rotation angles of0 and 90.8. Calibration and Standardization8.1 Calibration of these instrumen

33、ts is to be performedrelative to a known spectral or tristimulus standard from areliable source.E3165 1828.2 Calibration of Tristimulus DetectorsThe instrument isadjusted to read the reference standard chromaticity values.This may be done by calibration to a specific color or byverification using mu

34、ltiple colors ensuring that the readings areconsistent with the values on the standard.8.3 Calibration of Spectral Method Dispersing DevicesFor spectral measurements the calibration standard shall havespectral coefficient of retroreflection values from 380 to 740nmwitha5nmincrement anda5nmbandpass.

35、Theinstrument is then adjusted to read the correct values at eachwavelength before measurements are begun.8.4 Calibration of Light SourcesFor spectral energy dis-tribution of the source shall be proportional to CIE IlluminantA (a correlated color temperature of 2856 K, see PracticeE308). The project

36、ion lamp together with the projection opticsshall be operated such that they illuminate the test specimenwith this spectral power distribution.9. Measurement Geometry9.1 The observation angle () shall be 20 min of arc (0.33).The entrance angle (1) shall be 5 as described in PracticeE808.9.2 The maxi

37、mum angular size of the source and detector asviewed from the specimen or its optical equivalent shall be 10min of arc (0.167). In either case the source and the detectormay be interchanged. Examples of source and detector geom-etries using the required observation angle are shown in Fig.1(a) using

38、annular geometry and in Fig. 1(b) using pointgeometry.9.2.1 Note that Fig. 1 depicts a 10 min of arc (0.167)source/detector aperture. Other aperture sizes such as 6 min ofarc (0.10) may also be used. The size of the source/detectorapertures should be specified as part of the data reporting toevaluat

39、e the comparability of measurements made with differ-ent aperture sizes.9.3 Fig. 2 shows the general layout of source, receiver andspecimen in the laboratory. Instrumentation may also usecollimating optics to allow for smaller instrument sizes foreither field or laboratory bench measurements.10. Pro

40、cedure10.1 This method allows two procedures for determiningthe chromaticity coordinates of the test specimen: the tristimu-lus method and the spectral method. These methods aredescribed in Practice E811.10.2 Procedure AThe tristimulus method uses CIE Illu-minantAand appropriate tristimulus receptor

41、s as prescribed byCIE Publication 15. Calculations are performed for CIEIlluminant A and the CIE 1931 Standard Observer. Thismethod generates the chromaticity coordinates (x, y) forillumination using CIE Illuminant A.10.3 Procedure B uses the spectral method. For the spectralmethod the calculation o

42、f the spectral power distribution iscompleted and the chromaticity coordinates (x, y) for CIEIlluminant A and the CIE 1931 Standard Observer are calcu-lated as prescribed in CIE Publication 15.10.4 Either procedure may use a photometric range oroptically-reduced instruments for laboratory bench or f

43、ield use.In each case, the retroreflection geometry and aperture limita-tions shall be maintained11. Report11.1 The report shall contain the following:11.1.1 Sample identification,11.1.2 Equipment used (manufacturer name and model),11.1.3 Bandpass filter spectral width (5 nm or other value),11.1.4 S

44、ource and detector aperture angular size, and11.1.5 The individual chromaticity values (x, y) measuredand the average chromaticity values (x, y) for 0 and 90rotation angles ().11.1.6 Any deviation from the requirements stated in thistest method.12. Precision and Bias12.1 The precision and bias for t

45、his method is the same asreported in Practice E811. (More studies are recommended foruse of the reduced-optical-length instruments and their calibra-tion using substitutional standards.) From a practical view, theFIG. 1 Source and Detector Apertures for (a) Annular and (b) Point GeometriesE3165 183u

46、ncertainty in the (x, y) coordinates are generally consideredadequate if the uncertainty is about 0.005 or less.NOTE 4The analysis used in this P nighttime color; nighttime retroreflectedchromaticity; retroreflected chromaticity; retroreflected color;retroreflection; retroreflectiveFIG. 2 Geometry o

47、f Source, Receiver, and Specimen for Measurement (using the point source/receiver geometry)TABLE 1 Mean of Normalized DataRetroreflectance (RA) andChromaticity x, y ValuesTC 219 Panel DesignationRAxyEnclosedLens1 A(White) 96 0.4572 0.43052 B(Yellow) 48 0.5463 0.44513 C(Red) 25 0.6564 0.34214 D(Blue)

48、 6 0.1094 0.28265 E(Green) 10 0.1852 0.59376 F(Brown) 5 0.5972 0.39047 G(Orange) 30 0.6165 0.3712EncapsulatedLens8 H(White) 233 0.4589 0.42899 J(Yellow) 161 0.5549 0.441510 K(Red) 49 0.6769 0.320211 L(Blue) 23 0.1596 0.316112 M(Green) 43 0.1689 0.602013 N(Brown) 10 0.6136 0.3795PrismaticMaterials15

49、R(White) 783 0.4500 0.406516 S(Yellow) 648 0.5478 0.447817 T(Red) 172 0.6792 0.318618 U(Blue) 53 0.1386 0.250919 V(Green) 70 0.1751 0.685720 W(Orange) 385 0.6161 0.3828E3165 184TABLE 2 The Pooled Standard Deviation From the Mean ofChromaticity Measurements From Each of the 6 LaboratoriesTC-19 Panel DesignationxyEnclosed Lens1 A(White) 0.0005 0.00032 B(Yellow) 0.0003 0.00033 C(Red) 0.0003 0.00014 D(Blue) 0.0007 0.00155 E(Green) 0.0004 0.00166 F(Brown) 0.0025 0.00077 G(Orange) 0.0004 0.0002EncapsulatedLens8 H(Whi