1、Designation: E179 12E179 17Standard Guide forSelection of Geometric Conditions for Measurement ofReflection and Transmission Properties of Materials1This standard is issued under the fixed designation E179; the number immediately following the designation indicates the year oforiginal adoption or, i
2、n the case of revision, the year 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.INTRODUCTIONThis is a guide describing the selecting of geometric conditions of measurement of
3、 appearanceattributes such as color, gloss, reflectance, opacity, and transmittance. It includes a selection ofnumerical scales for appearance attributes other than color.In describing appearance, wavelength (or spectral) variability is primarily responsible for color,while geometric (or directional
4、) selectivity is primarily responsible for gloss, luster, translucency, andlike attributes. However, geometric conditions not only affect geometric variables such as gloss andtransparency, but also affect color, diffuse reflectance, and transmittance. Likewise spectral conditionscan affect the measu
5、rement of geometric attributes of appearance. Therefore both the spectral andgeometric conditions of measurement must be identified in specifying an appearance attribute of aspecimen.This guide describes the selection of geometric conditions and as a consequence should helpimprove agreement in these
6、 measurements as well as providing useful guidance in resolvingdifferences between spectral-type measurements that are related to geometry.1. Scope1.1 This guide is intended for use in selecting terminology, measurement scales, and instrumentation for describing orevaluating such appearance characte
7、ristics as glossiness, opacity, lightness, transparency, and haziness in terms of reflected ortransmitted light. This guide does not consider the spectral variations responsible for color, but the geometric variables describedherein can importantly affect instrumentally measured values of color. Thi
8、s guide is general in scope rather than specific as toinstrument or material.1.2 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and R
9、ecommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2C346 Test Method for 45-deg Specular Gloss of Ceramic MaterialsC347 Test Method for Reflectivity and Coefficient of Scatter of White Porcelain Enamels (Withdraw
10、n 1990)3C523 Test Method for Light Reflectance of Acoustical Materials by the Integrating Sphere Reflectometer (Withdrawn 1988)3C584 Test Method for Specular Gloss of Glazed Ceramic Whitewares and Related ProductsD523 Test Method for Specular GlossD1003 Test Method for Haze and Luminous Transmittanc
11、e of Transparent PlasticsD1455 Test Method for 60 Specular Gloss of Emulsion Floor PolishD1494 Test Method for Diffuse Light Transmission Factor of Reinforced Plastics PanelsD1746 Test Method for Transparency of Plastic Sheeting1 This guide is under the jurisdiction of ASTM Committee E12 on Color an
12、d Appearance and is the direct responsibility of Subcommittee E12.03 on Geometry.Current edition approved July 1, 2012May 1, 2017. Published September 2012July 2017. Originally approved in 1961. Last previous edition approved in 20032012 asE179 96 (2003) which was withdrawn April 2012 and reinstated
13、 in July 2012. DOI: 10.1520/E0179-1212. DOI: 10.1520/E0179-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website
14、.3 The last approved version of this historical standard is referenced on www.astm.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to
15、 adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Cons
16、hohocken, PA 19428-2959. United States1D1834 Test Method for 20 Specular Gloss of Waxed Paper (Withdrawn 2004)3D4039 Test Method for Reflection Haze of High-Gloss SurfacesD4061 Test Method for Retroreflectance of Horizontal CoatingsE97 Method of Test for Directional Reflectance Factor, 45-Deg 0-Deg,
17、 of Opaque Specimens by Broad-Band FilterReflectometry (Withdrawn 1991)3E167 Practice for Goniophotometry of Objects and Materials (Withdrawn 2005)3E284 Terminology of AppearanceE429 Test Method for Measurement and Calculation of Reflecting Characteristics of Metallic Surfaces Using Integrating Sphe
18、reInstruments (Withdrawn 1996)3E430 Test Methods for Measurement of Gloss of High-Gloss Surfaces by Abridged GoniophotometryE808 Practice for Describing RetroreflectionE809 Practice for Measuring Photometric Characteristics of RetroreflectorsE810 Test Method for Coefficient of Retroreflection of Ret
19、roreflective Sheeting Utilizing the Coplanar GeometryE811 Practice for Measuring Colorimetric Characteristics of Retroreflectors Under Nighttime ConditionsE991 Practice for Color Measurement of Fluorescent Specimens Using the One-Monochromator MethodE1164 Practice for Obtaining Spectrometric Data fo
20、r Object-Color EvaluationE1331 Test Method for Reflectance Factor and Color by Spectrophotometry Using Hemispherical GeometryE1348 Test Method for Transmittance and Color by Spectrophotometry Using Hemispherical GeometryE1349 Test Method for Reflectance Factor and Color by Spectrophotometry Using Bi
21、directional (45:0 or 0:45) GeometryE1767 Practice for Specifying the Geometries of Observation and Measurement to Characterize the Appearance of MaterialsE2194 Test Method for Multiangle Color Measurement of Metal Flake Pigmented MaterialsE2539 Test Method for Multiangle Color Measurement of Interfe
22、rence PigmentsF768 Test Method for Specular Reflectance and Transmittance Measurements of Optically Flat-Coated and Non-CoatedSpecimens (Withdrawn 1994)32.2 CIE Publications:4CIE Publication No. 15.215 Colorimetry, second edition 1986ColorimetryCIE Publication No. 17.417 International Lighting Vocab
23、ulary, fourth edition, 1987VocabularyCIE Publication No. 38 Radiometric and Photometric Characteristics of Materials and Their Measurement, 1977Measurement3. Terminology3.1 Definitions:3.1.1 flux (radiant), , nthe time rate of flow of radiant energy; radiant power (Terminology E284).3.1.2 incident f
24、lux, i, nflux incident on the specimen at a specified illumination angle and aperture angle.3.1.3 reflected flux, r, nflux reflected from the specimen at a specified viewing angle and aperture angle.3.1.4 reference reflected flux, r.r, nflux reflected from a reference standard of reflectance, illumi
25、nated and viewed in the samemanner as the specimen under consideration.3.1.5 transmitted flux, t, nflux transmitted through the specimen at a specified viewing angle and field angle.3.1.6 reflectance, , nratio of the reflected flux to the incident flux defined as = = r / i. .3.1.7 reflectance factor
26、, R, nratio of the reflected flux to the reference reflected flux defined as R = r / r.r.3.1.8 transmittance, , nratio of the transmitted flux to the incident flux defined as = t / i.3.1.8.1 DiscussionA companion term, transmittance factor, is not normally used in the measurement of appearance attri
27、butes.3.1.9 For other definitions see Terminology E284 and CIE Publication Nos. 17.417 and 38.4. Summary of Guide4.1 When light impinges upon a material, several phenomena can occur. Part of the light may be reflected, part may betransmitted, and part may be absorbed. This guide deals with the refle
28、cted and transmitted light and the selection of geometricconditions for its measurement.4.2 An idealization of the light reflected and transmitted by a material is shown in Fig. 1. Fig. 2 illustrates luminancelightdistributions more like those actually encountered in practice.4 Information on how to
29、 obtain CIE documents shouldmay be requested from the U.S. National Committee, CIE, c/o Radiometric Physics Division, National Institute ofStandards and Technology, Bldg. 220, Room B-306, Gaithersburg, MD 20899.obtained from CIE (International Commission on Illumination), http:/www.cie.co.at orhttp:
30、/.E179 172FIG. 3 Designations of Flux, , and Angles , , for Reflectance and Transmittance MeasurementFIG. 1 Idealizations of Reflection and Transmission Phenomena, Showing ComponentsFIG. 2 Representations of Actual Reflection and Transmission Phenomena with Mixtures of ComponentsTABLE 1 Differences
31、Between Concepts of Regular (Specular)and Diffuse Components of Reflection and TransmissionMeasurementGeometricDistribution ofLightStructuralElementsResponsibleResultingAppearanceCharacteristicWhenComponentDominatesReflectance:Specularcomponentreflected only indirection of mirrorreflectionsmoothness
32、 of surfaceor skin of specimenglossiness orshininessDiffusecomponentdistributed in alldirectionspigment granules andcavities withinspecimen, surfaceroughnesslightness(expressed onblack-gray-whitescale)Transmittance:Regularcomponenta continuation of theincident beamclear homogeneousmedium with plane,
33、parallel facesclearness ortransparencyDiffusecomponentdistributed in alldirectionsscattering andrefracting particles of anonopaque specimen,surface roughnesstranslucency,turbidity, orhazinessE179 1735. Types of Measurement Scales5.1 Type of ScaleThe terms defined in 3.1.6 3.1.8 to may be further ide
34、ntified by a preceding adjective, such as specular,regular, diffuse, total, or directional, thereby identifying the basis for the measurement scale. The significance of each of theseadjectives is as follows:5.1.1 regularindicates that only light that has been reflected or transmitted without scatter
35、ing or diffusion is included formeasurement. When a specimen scatters or diffuses the incident light on reflection or transmission, the values obtained will dependon the angular size of the illuminator and receiver used in the measurement.5.1.2 specularindicates that only the light that is mirror-re
36、flected is included for measurement. The CIE prefers the modifierregular instead of specular although specular reflectance is recognized. Specular has also sometimes been used to refer to regulartransmittance. This is a misnomer because specular refers to a mirror.5.1.3 diffuseindicates that only th
37、e light reflected or transmitted in directions other than the specular or regular direction isincluded in the measurement.NOTE 1The differences between the concepts of regular and diffuse components of reflection and transmission are shown in Table 1.5.1.4 totalindicates that the light reflected or
38、transmitted in all directions is included for measurement.5.1.5 directionalindicates that the light reflected or transmitted in specified directions only is included for measurement.Directional values depend on the illumination and viewing angles and refer to light reflected or transmitted in direct
39、ions that differmoderately from the centroid direction or axis of the beam.6. Geometric Directions of Incidence and Viewing6.1 Geometric directions may be identified by preceding the adjective with the angular directions, by including a detailedgeometric description, or by placing after the symbols
40、a subscript that represents the measurement condition.NOTE 2This guide is concerned with bidirectional or hemispherical measurement systems. For gonophotometricgonioapparent methods, seePracticeSection E1678.4. For methods of specifying the geometry of measurements, see Practice E1767.6.2 illuminati
41、on and viewing anglesthe angles of illumination and viewing are identified as follows (see Fig. 3):6.2.1 illumination angle, ithe angle between the incident-beam axis and the normal (perpendicular) to the surface of thespecimen (the specimen normal).6.2.2 viewing angle for reflection, rangle between
42、 the surface normal and the axis of the receiver.6.2.3 viewing angle for transmission, tangle between the axis of the transmitted beam and the axis of the receiver.FIG. 3 Designations of Flux, , and Angles , , for Reflectance and Transmittance MeasurementE179 1746.3 aperture anglesthe angles subtend
43、ed at a point on the specimen by the maximum dimension of the apparent illuminatorand receiver. They are a necessary part of the geometric specification because the finite size of every practical illuminator limitscollimation.6.4 azimuthal angle, the angle between the plane containing the illuminato
44、r axis and the specimen normal and the planecontaining the receiver axis and the specimen normal. Unless an azimuthal angle is specified, the illuminator axis, the specimennormal, and the receiver axis are taken to be in the same plane.6.5 rotation angle, the angle indicating the orientation of the
45、test specimen when it is rotated in its own plane. The orientationof the specimen is considered to be part of the specimen description in this guide (see 12.2.7).6.6 Complete geometric specifications are necessary for measuring such geometrically dependent factors as gloss, transparency,and haze. Fo
46、r ideally specular or ideally regular or diffuse reflection or transmission, specification of only the directions ofillumination and view is usually adequate.7. Measured Quantities7.1 The following quantities, defined and described in more detail in the Illuminating and Viewing Conditions section of
47、Practice E1164 and in CIE Publication No. 15.2,15, are those most commonly measured by spectrophotometry and tristimulus(filter) colorimetry for the assessment of color and related appearance attributes.7.1.1 45/normal (45/0) and normal/45 (0/45) reflectance factorfor the 45/0 condition, the specime
48、n is illuminated by oneor more beams at an angle of 45 from the specimen normal to the specimen surface. The angle between the direction of viewingand the specimen normal should not exceed 10. For the 0/45 condition, these requirements are interchanged. Suitable restrictionson the angles of illumina
49、tion and viewing and on the aperture angles should be observed.7.1.2 total/normal (t/0) or diffuse/normal (d/0) and normal/total (0/t) or normal/diffuse (0/d) reflectance factorfor the t/0 ord/0 conditions, the specimen is illuminated diffusely, for example by an integrating sphere. The angle between the normal to thespecimen surface and the direction of viewing should not exceed 10. If all specularly reflected light is included in themeasurements, the condition is t/0; if all specularly
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