1、Designation: E 2152 01 (Reapproved 2006)Standard Practice forComputing the Colors of Fluorescent Objects fromBispectral Photometric Data1This standard is issued under the fixed designation E 2152; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、 of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.INTRODUCTIONThe fundamental procedure for evaluating the color of a fluorescent specimen is to obtain b
3、ispectralphotometric data for specified irradiating and viewing geometries, and from these data to computetristimulus values based on a CIE (International Commission on Illumination) standard observer anda CIE standard illuminant. Procedures for such computation are contained in this practice. Thisp
4、ractice also contains procedures for computing illuminant-specific spectral radiance factor valuesfrom illuminant-independent bispectral photometric data.1. Scope1.1 This practice provides the values and practical compu-tation procedures needed to obtain tristimulus values, desig-nated X, Y, Z and X
5、10,Y10,Z10for the CIE 1931 and 1964observers, respectively, from bispectral photometric data forthe specimen. Procedures for obtaining such bispectral photo-metric data are contained in Practice E 2153.1.2 Procedures for conversion of results to color spaces thatare part of the CIE system, such as C
6、IELAB and CIELUV arecontained in Practice E 308.1.3 This standard may involve hazardous materials, opera-tions, and equipment. This standard does not purport toaddress all of the safety concerns, if any, associated with itsuse. It is the responsibility of the user of this standard toestablish approp
7、riate safety and health practices and deter-mine the applicability of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E 284 Terminology of AppearanceE 308 Practice for Computing the Colors of Objects byUsing the CIE SystemE 2153 Practice for Obtaining Bispectral Photom
8、etric Datafor Evaluation of Fluorescent Color2.2 CIE Standards:CIE Publication 15.2, Colorimetry32.3 ISO Standards:ISO 11476 Paper and BoardDetermination of CIE-Whiteness, C/2 Degrees43. Terminology3.1 DefinitionsThe definitions contained in TerminologyE 284 are applicable to this practice.3.2 Defin
9、itions of Terms Specific to This Standard:3.2.1 bispectrometer, nan optical instrument equippedwith a source of irradiation, two monochromators, and adetection system, such that a specimen can be measured atindependently-controlled irradiation and viewing wavelengths.The bispectrometer is designed t
10、o allow for calibration toprovide quantitative determination of the bispectral radiation-transfer properties of the specimen.(5)NOTE 1Typically, a reference detection system monitors the radiationincident on the specimen. This reference detection system serves tocompensate for both temporal and spec
11、tral variations in the flux incidentupon the specimen, by normalization of readings from the instrumentsemission detection system.3.2.2 diagonal elements, nelements of a bispectral matrixfor which irradiation and viewing wavelengths are equal.3.2.3 fluorescence, nthis standard uses the term “fluores
12、-cence” as a general term, including both true fluorescence(with a luminescent decay time of less than 10-8s) and1This practice is under the jurisdiction of ASTM Committee E12 on Color andAppearance and is the direct responsibility of Subcommittee E12.05 on Fluores-cence.Current edition approved Dec
13、. 1, 2006. Published December 2006. Originallyapproved in 2001. Last previous edition approved in 2001 as E 2152 - 01.2For 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 t
14、o the standards Document Summary page onthe ASTM website.3Available from U.S. National Committee of the CIE (International Commissionon Illumination), C/o Thomas M. Lemons, TLA-Lighting Consultants, Inc., 7 PondSt., Salem, MA 01970, http:/www.cie-usnc.org.4Available from American National Standards
15、Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.phosphorescence with a delay time short enough to be indis-tinguishable from fluorescence for the purp
16、ose of colorimetry.3.2.4 off-diagonal element, nany element of a bispectralmatrix for which irradiation and viewing wavelengths are notequal.4. Summary of Practice4.1 ProceduresProcedures are given for computing frombispectral photometric measurements the CIE tristimulus val-ues X, Y, Z for the CIE
17、1931 standard observer and the CIE1964 supplementary standard observer. While recognizing theCIE recommendation of numerical integration at 1 nm intervals(in Publication 15.2) as the basic definition, this practice islimited in scope to measurements and calculations usingspectral intervals greater t
18、han or equal to 5 nm.4.2 CalculationsCIE tristimulus values X, Y, Z or X10,Y10,Z10are calculated by numerical summation of the prod-ucts of weighting factors for selected illuminants and observerswith the bispectral Donaldson radiance factor of the specimen.The tristimulus values so calculated may b
19、e converted tocoordinates in a more nearly uniform color space such asCIELAB or CIELUV.5. Significance and Use5.1 The bispectral or two-monochromator method is thedefinitive method for the determination of the generalradiation-transfer properties of fluorescent specimens (4).Inthis method, the measu
20、ring instrument is equipped with twoseparate monochromators. The first, the irradiation monochro-mator, irradiates the specimen with monochromatic light. Thesecond, the viewing monochromator, analyzes the radiationleaving the specimen. A two-dimensional array of bispectralphotometric values is obtai
21、ned by setting the irradiationmonochromator at a series of fixed wavelengths () in theultraviolet and visible range, and for each , using the viewingmonochromator to record readings for each wavelength (l) inthe visible range. The resulting array, once properly corrected,is known as the Donaldson ma
22、trix, and the value of eachelement (,l) of this array is here described as the Donaldsonradiance factor (D(,l). The Donaldson radiance factor is aninstrument- and illuminant-independent photometric propertyof the specimen, and can be used to calculate its color for anydesired illuminant and observer
23、. The advantage of this methodis that it provides a comprehensive characterization of thespecimens radiation-transfer properties, without the inaccura-cies associated with source simulation and various methods ofapproximation.6. Procedure6.1 Selecting Standard ObserverSelect standard observeraccordi
24、ng to the guidelines of Practice E 308.6.2 Selecting IlluminantsSelect illuminants that are simi-lar to the light under which the objects will be viewed or forwhich their colors will be specified or evaluated. In general,follow the recommendations of Practice E 308. For fluorescentsamples, however,
25、special attention must be given to therelative UV content of the selected illuminants and the lightunder which the objects will be viewed.6.2.1 When object will be viewed indoors, by daylightfiltered through a glass window, use values for the extendedversion of Illuminant C defined in ISO 11476.6.2.
26、2 When object will be viewed outdoors, by unfiltereddaylight, use values for CIE Illuminant D65, or other daylightilluminants, as defined by the formulas developed by Judd, andpresented in CIE 15.2.6.2.3 When object will be viewed under well-defined spe-cial conditions of irradiation which are not s
27、imilar to anystandard illuminant, a provisional illuminant may be defined.Such a provisional illuminant must represent the relativespectral irradiance upon the object surface under these specialconditions.7. Calculation7.1 Calculation of Colorimetric QuantitiesUse themethod of calculating tristimulu
28、s values at 5 nm intervals overthe viewing wavelength range 380 to 780 nm, and irradiationwavelength range 300 to 780 nm.7.2 Calculation of Tristimulus ValuesThe calculation pro-cedures described below involve numerical summation of theproducts of the Donaldson radiance factor of the specimen anda b
29、ispectral factor derived from the tabulated standard illumi-nant and observer functions. After normalization, the sums arethe CIE tristimulus values X, Y, Z. (3, 4, 5)7.2.1 Application of Illuminant WeightsSelect the desiredCIE standard illuminant from Tables given in Practice E 308.Multiply each el
30、ement D(,l) of the specimens Donaldsonmatrix by the tabulated value of the relative spectral power ofthe illuminant F at the elements irradiation wavelength ().7.2.2 Calculation of Stimulus FunctionObtain the sumover of these products at 5 nm intervals over the wavelengthrange 300 to 780 nm. The sum
31、 obtained at each viewingwavelength l is the value of the specimens stimulus function(relative spectral radiance) F(l), under the specified conditionsof irradiation. From these values, either tristimulus values orspectral radiance factor values may be derived.Fl! 5( 5 300780F!D,l! (1)7.2.3 Derivatio
32、n of Tristimulus ValuesUse the color-matching functions selected in 6.1. Multiply the specimensstimulus function at each viewing wavelength (l) by thecorresponding tabulated values of the observer color-matchingfunctions. Obtain the sum of these spectral products at 5 nmintervals over the wavelength
33、 range 380 to 780 nm:X 5 k(l5380780xl!Fl! (2)Y 5 k(l5380780yl!Fl!Z 5 k(l5380780zl!Fl!where:k = the normalization constant:k 5100(l5380780Fl!yl!(3)E 2152 01 (2006)27.3 Derivation of Other Colorimetric QuantitiesOthercolorimetric values, such as chromaticity coordinates, CIELABand CIELUV values, may b
34、e calculated from tristimulus valuesas described in Practice E 308.NOTE 2The validity of CIELAB and CIELUV values for describingthe color of fluorescent materials is subject to question, for two reasons.First, because the appearance of a fluorescent material may be influencedby irradiation at wavele
35、ngths outside the visible range, the appropriatedefinition of the “ white point” (incorporated in the CIELAB and CIELUVcalculations) is not clear. Second, the perceptual uniformity of these colorspaces has not been evaluated in regions where L* exceeds 100, as it mayfor fluorescent materials. It is
36、the responsibility of the user to determinethe appropriateness of such metrics for any particular specimen andapplication.7.4 Derivation of Spectral Radiance FactorsCalculate thespecimens stimulus function (relative spectral radiance) F(l)for the selected illuminant as described in section 7.2.2. Di
37、videF at each viewing wavelength (l) by the correspondingtabulated value of the relative spectral power FIof the selectedilluminant. Note that for a fluorescent specimen, the spectralradiance factor (bI(l) is illuminant-specific. (3)bIl! 5FIl!FIl!5( 5 300780FI!FIl!D,l! (4)7.5 Separation of Fluoresce
38、nce and ReflectionComponentsFluorescence and reflection components of tri-stimulus and spectral radiance factor values can be calculatedby substituting the fluorescent or reflection components ofDonaldson radiance factor (DFor DR) for Donaldson radiancefactor (D) in the calculations described in sec
39、tions 7.2 and 7.3.This separation of components is valid for D, b, and tristimulusvalues; it may not be valid for other colorimetric values.7.5.1 Estimation of ComponentsTo a first approximation,the contribution of fluorescence and reflectance to the appear-ance of the specimen can be separated by t
40、reating diagonalvalues of the Donaldson matrix as representing reflectanceonly, and off-diagonal values as representing fluorescence.7.5.2 Calculation of ComponentsWhile more rigorousand accurate methods for the separation of reflection andfluorescence components may be employed, description ofsuch
41、calculations lies outside the scope of this standard.7.6 Abridged Calculation Procedures:7.6.1 Wavelength Intervals of Greater than 5 nmWhendata for D(,l) are not available at 5 nm intervals, estimatedvalues at 5 nm intervals should be derived by appropriateinterpolation, as described in Annex A1.7.
42、6.2 Viewing Wavelength Range Less Than 380-780 nmWhen data for D(,l) are not available for the full viewingwavelength range, add the illuminant or observer weights, orboth, at the wavelengths for which data are not available to theweights at the shortest and longest wavelength for whichspectral data
43、 are available. Note that such use of spectrally-truncated data is not recommended when significant fluores-cent emission occurs in the region of truncation.7.6.3 Irradiation Wavelength Range Less Than 300-780nmWhen the bispectral region of fluorescence is known fora particular specimen, it is accep
44、table to limit the collection offluorescence data (off-diagonal values) to this region. Com-plete the standard Donaldson matrix by setting off-diagonalvalues outside this region to zero.8. Report8.1 The report of the measurement of colorimetric forfluorescent samples data shall include the following
45、:8.2 Specimen DescriptionIncluding the following:8.2.1 Type and identification,8.2.2 Date of preparation or manufacture, if required,8.2.3 Method of cleaning and date, if cleaned,8.2.4 Orientation of the specimen during measurement, and8.2.5 Any changes in the specimen during measurement.8.3 Source
46、of DateGive instrument identification, irradi-ating and viewing geometry, spectral bandpass, and date ofmeasurement.8.4 ObserverIndicate whether the reported data werecomputed for the CIE 1931 standard observer (2) or the 1964supplementary standard observer (10).8.5 IlluminantsIndicate which illumin
47、ants were used.8.6 Method of CalculationIndicate whether the procedureusinga5nmwavelength interval, or a specified abridgedprocedure was used, and what wavelength range of spectraldata was available.8.7 Colorimetric DataReport according to the guidelinesof Practice E 308.8.8 Spectral Radiance Factor
48、 (Optional)When reportingspectral radiance factor values for fluorescent samples, indicatefor which illuminant the reported spectral radiance factor isdefined.9. Keywords9.1 bispectral; bispectrometer; color; colorimetry; Donald-son matrix; Donaldson radiance factor; fluorescence; lumines-cence; rad
49、iance factor; tristimulusE 2152 01 (2006)3ANNEX(Mandatory Information)A1. BISPECTRAL INTERPOLATION PROCEDUREA1.1 DiscussionThis annex presents a procedure forbispectral Lagrange interpolation, appropriate for deriving the5 nm interval data required in Section 7 from abridgedbispectral data.A1.1.1 Alternate MethodsOther methods of interpolationmay be equally appropriate, and some may yield more accurateresults than Lagrange interpolation, but consideration of thesealternatives lies beyond the scope of t
