1、Designation: E1348 11Standard Test Method forTransmittance and Color by Spectrophotometry UsingHemispherical Geometry1This standard is issued under the fixed designation E1348; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the ye
2、ar of last 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 measure-ment of the transmission properties and color of object-colo
3、rspecimens by the use of a spectrophotometer or spectrocolo-rimeter with a hemispherical optical measuring system, such asan integrating sphere.1.2 This test method is generally suitable for all fullytransparent specimens without regard for the specimen positionrelative to the transmission port of t
4、he instrument. Translucentspecimens, however, must be placed flush against the trans-mission port of the sphere.1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.4 This standard does not purport to address all of thesafety c
5、oncerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1003 Test Method for Haze and Lumin
6、ous Transmittanceof Transparent PlasticsD2244 Practice for Calculation of Color Tolerances andColor Differences from Instrumentally Measured ColorCoordinatesE179 Guide for Selection of Geometric Conditions forMeasurement of Reflection and Transmission Properties ofMaterialsE284 Terminology of Appear
7、anceE308 Practice for Computing the Colors of Objects byUsing the CIE SystemE805 Practice for Identification of Instrumental Methods ofColor or Color-Difference Measurement of MaterialsE1164 Practice for Obtaining Spectrometric Data forObject-Color Evaluation3. Terminology3.1 Definitions:3.1.1 The d
8、efinitions in Guide E179, Terminology E284,and Practice E1164 are applicable to this test method.4. Summary of Test Method4.1 This test method provides a procedure for measuring thetransmittance of transmitting specimens by using a spectropho-tometer or spectrocolorimeter equipped with a hemispheric
9、aloptical measuring system such as an integrating sphere.4.2 This test method includes procedures for calibrating theinstrument and for selecting specimens suitable for precisionmeasurement.4.3 This test method is satisfactory for all fully transparentspecimens with plane and parallel surfaces. When
10、 possible, theuser should select the position of the specimen in the trans-mission compartment to provide either essentially total oressentially regular transmittance, depending on the end use ofthe measured data.4.4 Accurate measurement of translucent specimens re-quires that the specimen be placed
11、 flush against the transmis-sion port of the integrating sphere (see Practice E1164, 8.1.4).4.5 Most modern spectrophotometers have the capacity tocompute the color coordinates of the specimen during themeasurement. When this is the case, the user of this testmethod must select the color system, obs
12、erver, and illuminant(see the Procedure section in Practice E308, Section 6).5. Significance and Use5.1 The most direct and accessible methods for obtainingthe color coordinates of object colors are by instrumentalmeasurement using spectrophotometers or colorimeters with1This test method is under th
13、e jurisdiction of ASTM Committee E12 on Colorand Appearance and is the direct responsibility of Subcommittee E12.02 onSpectrophotometry and Colorimetry.Current edition approved Nov. 1, 2011. Published December 2011. Originallyapproved in 1990. Last previous edition approved in 2007 as E1348 - 02 (20
14、07).DOI: 10.1520/E134811.2For 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.1Copyright ASTM International, 100 B
15、arr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.either hemispherical or bidirectional optical measuring sys-tems. This test method provides procedures for such measure-ment by transmittance spectrophotometry using a hemispheri-cal optical measuring system.5.2 This test
16、 method is especially suitable for measurementof the following types of specimens (see also Guide E179 andPractice E805):5.2.1 Fully transparent specimens (free from turbidity, haze,or translucency), and5.2.2 Translucent or hazy specimens, provided that thespecimen can be placed flush against the tr
17、ansmission port ofthe integrating sphere.5.3 This test method is not recommended for measurementof retroreflective transparent or translucent specimens, orsamples that are fluorescent.6. Apparatus6.1 Spectrophotometer or Spectrocolorimeter, designed forthe measurement of color coordinates of transmi
18、tting speci-mens by use of integrating-sphere geometry.6.2 Calibration Standards, either supplied by the instrumentmanufacturer or obtained separately, as follows (see PracticeE1164, Section 10):6.2.1 White Tile or Pressed-Powder Reflectance Standard,to be placed at the reflection port of the integr
19、ating sphere(mandatory).6.2.2 Calibration Standards, for (1) setting or verifying zeroon the photometric scale; (2) verifying the wavelength scale,and (3) evaluating stray light (optional).6.2.3 Verification Standards (recommended) (see PracticeE1164, 10.5).7. Test Specimen7.1 For highest precision
20、and accuracy, select specimenswith the following properties (see Practice E1164, Section 9):7.1.1 High material uniformity and freedom from blemishesin the area to be measured, and7.1.2 Specimens that have two essentially plane and parallelsurfaces, and that have a standard thickness, if one is defi
21、ned.8. Calibration and Verification8.1 Calibrate or verify the calibration of the followingquantities (see Practice E1164, Section 10):8.1.1 Zero setting of the transmittance scale (mandatory),8.1.2 Wavelength scale (recommended), and8.1.3 Stray-light level (optional).8.2 Calibrate the full-scale va
22、lue of the transmittance scaleof the instrument with no transmitting specimen in place andthe white reflectance standard at the reflection port. Follow theinstrument manufacturers instructions (mandatory).NOTE 1For maximum accuracy of measurement of translucent speci-mens, the white standard at the
23、reflection port should have the samereflectance as that of the lining of the integrating sphere.8.3 Verify the accuracy of the measured results by measure-ment of a series of verification standards (recommended) (seePractice E1164, 10.5).9. Procedure9.1 When required, select the color scales, observ
24、er, andilluminant to be used in the computation of color coordinates(see the Procedure section in Practice E308, Section 6).9.2 Select settings of other options, such as wavelengthrange and interval, when required. Follow the instrumentmanufacturers instructions or specified procedures.9.3 Handle th
25、e specimen carefully; avoid touching the areato be measured. When necessary, clean the specimen by anagreed procedure.9.4 For the measurement of fully transparent specimens,place the specimen in the transmission compartment of theinstrument.9.4.1 If total transmittance is desired, place the specimen
26、flush against the transmission measurement port of the inte-grating sphere.9.4.2 If regular transmittance is desired, place the specimenin the transmission compartment, but as far away from thesphere port as possible.9.5 For the measurement of translucent specimens, place thespecimen in the transmis
27、sion compartment, flush against thetransmission measurement port of the integrating sphere. Formaximum accuracy in the measurements, the white standard atthe reflection port should have the same reflectance as that ofthe lining of the integrating sphere (see Practice E1164, 8.1.4).NOTE 2When the siz
28、e and centering of the light beam at the reflectionmeasurement port of the integrating sphere can be properly adjustedaccording to Test Method D1003, it is possible to measure transmissionhaze accurately. A set of haze standards should be used to verify theaccuracy of the measurements.9.6 Measure th
29、e specimen, following the instrument manu-facturers instructions.9.7 Transcribe the data required for the report, when notprinted by the instrument.10. Calculation10.1 Perform any desired calculations of color coordinatesthat are not made automatically by the instrument (see PracticeD2244 and Practi
30、ce E308).11. Report11.1 Report the following information:11.1.1 Specimen description (see Practice E1164, 12.1.1),11.1.2 Date of measurement,11.1.3 Instrument parameters and specimen position asselected in Section 9, and11.1.4 Measurement results, in the form of tables of trans-mittance versus wavel
31、ength or color-scale values.12. Precision and Bias12.1 PrecisionThe precision estimates are composed ofthree additive terms. The first term represents the noisecomponent of any measurement. The second term representsmeasurement uncertainty introduced by factors dependentupon the first derivative of
32、the transmittance function of thespecimen. The third term represents uncertainty introduced byfactors dependent upon the absolute magnitude of the trans-mittance value at any wavelength. For complex transmittanceE1348 112functions such as a didymium filter a more complex model ofthe derivative is re
33、quired than the linear model offered here.Hence complex spectra may be expected to fail the testdescribed below at or near their transmittance maxima andminima. In addition, reporting intervals greater than 10 nmmay also fail.12.1.1 RepeatabilityMeasurements should be consideredsuspect if the sample
34、 standard deviation of four spectraltransmittance values measured under repeatability conditions islarger at most wavelengths than the limit defined by thefollowing equation:sMAXl! 5 0.02 1 ABSFTl210! 2 Tl110!200G1Tl!1000(1)sMAX(l) = maximum allowable sample standard devia-tion at any wavelengthT(l)
35、 = mean of four readings of T at that wavelengthand the units of T(l) are percent transmittancel = wavelength in nm currently under consider-ation.The units of the calculated limit are therefore percenttransmittance. A 10 nm wavelength measurement interval isassumed in this example. For measurements
36、 at 20 nm interval,the constants in the second additive term are 20, 20, and 400respectively. In either case, the first and last measured intervalsare ignored.12.1.2 ReproducibilityMeasurements should be consid-ered suspect if the absolute value of the difference between twospectral transmittance va
37、lues measured under reproducibilityconditions is larger at most wavelengths than the limit definedby the following equation:DTl! 5 0.08 1 ABSFTl210! 2 Tl110!200G1Tl!100(2)where the units, symbols, and procedure are identical tothose of Eq 1.NOTE 3Sometimes one of the two spectral transmittance value
38、smeasured under reproducibility conditions is the set of tabular values of acalibration verification standard, and the other set of values is thatverification standard measured on an individual instrument for the purposeof verification of calibration of the instrument. Under these conditions, ifthe
39、pair fails the above test, the instrument may be considered suspect, andmay fail calibration verification.12.2 BiasThere is no known bias in this method.13. Keywords13.1 color; integrating sphere; spectrophotometer; translu-cent; transmittance; transparentASTM International takes no position respect
40、ing the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This stan
41、dard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM Internatio
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