IESNA LM-78-2017 Approved Method Total Flux Measurement of Lamps Using an Integrating Sphere.pdf

1、Approved Method Total Flux Measurement of Lamps Using an Integrating SphereIES LM-78-17IES LM-78-17IES Approved Method for Total Flux Measurement of LampsUsing an Integrating SpherePublication of this Lighting Measurementhas been approved by the IES.Suggestions for revisions should be directed to th

2、e IES.Copyright 2017 by the Illuminating Engineering Society.Approved by the IES Standards Committee, January 9, 2017, as a Transaction of the IlluminatingEngineering Society.All rights reserved. No part of this publication may be reproduced in any form, in any electronic retrieval system or otherwi

3、se, without prior written permission of the IES.Published by the Illuminating Engineering Society, 120 Wall Street, New York, New York 10005.IES Standards and Guides are developed through committee consensus and produced by the IES Office in New York. Careful attention is given to style and accuracy

4、. If any errors are noted in this document, please forward them to Brian Liebel, IES Director of Standards and Research, at the above address for verification and correction. The IES welcomes and urges feedback and comments. ISBN # 978-0-87995-357-7Printed in the United States of America.DISCLAIMERI

5、ES publications are developed through the consensus standards development process approved by the American National Standards Institute. This process brings together volunteers representing varied viewpoints and interests to achieve consensus on lighting recommendations. While the IES administers th

6、e process and establishes policies and procedures to promote fairness in the development of consensus, it makes no guaranty or warranty as to the accuracy or completeness of any information published herein. The IES disclaims liability for any injury to persons or property or other damages of any na

7、ture whatsoever, whether special, indirect, consequential or compensatory, directly or indirectly resulting from the publication, use of, or reliance on this documentIn issuing and making this document available, the IES is not undertaking to render professional or other services for or on behalf of

8、 any person or entity. Nor is the IES undertaking to perform any duty owed by any person or entity to someone else. Anyone using this document should rely on his or her own independent judgment or, as appropriate, seek the advice of a competent professional in determining the exercise of reasonable

9、care in any given circumstances.The IES has no power, nor does it undertake, to police or enforce compliance with the contents of this document. Nor does the IES list, certify, test or inspect products, designs, or installations for compliance with this document. Any certification or statement of co

10、mpliance with the requirements of this document shall not be attributable to the IES and is solely the responsibility of the certifier or maker of the statement.Prepared by The IES Testing Procedures Sub-Committee on Photometry of Light SourcesSteven Long, ChairIES Testing Procedures CommitteeC. Cam

11、eron Miller, ChairRebecca Kuebler, Vice ChairDavid Ellis, SecretaryJianzhong Jiao, TreasurerL. Ayers*R. BergmanE. Bretschneider*E. Carter*D. Chan*G. Connelly*R. Daubach*J. Demirjian*M. Duffy*P. Elizondo*S. Ellersick*D. EllisB. Feagin*A. Gelder*P.-C. Hung*A. JacksonD. Karambelas*T. Kawabata*M. Kotreb

12、aiJ. Leland*R. Low*J. MarellaG. McKeeD. Miletich*C. MillerM. Nadal*Y. Ohno*M. Piscitelli*B. Rao*S. Rao*D. Rogers*M. SapcoeK. Tracy*V. Wu*R. Young*G. Yu*Y. Zong* Advisory*HonoraryC. AndersenL. AyersA. BakerR. BergerR. Bergin*R. BergmanC. Bloomfield*E. BretschneiderK. Broughton*E. Carter*D. Chan*P.-T.

13、 Chou*G. Connelly*J. Creveling*J. Dakin*R. Daubach*L. Davis*J. Demirjian*M. Duffy*P. ElizondoP. Franck*J. Fye*A. Gelder*M. GratherY. Guan*K. Haraguchi*R. Heinisch*K. Hemmi*Y. Hiebert*R. Higley*R. Horan*J. HospodarskyS. Hua*J. HulettP-C. HungD. Husby*A. JacksonD. Jenkins*J. JiaoD. Karambelas*H. Kasha

14、ni*T. Kawabata*R. Kelley*M. KotrebaiJ. Lawton*L. Leetzow*J. Leland*K. Lerbs*R. Levin*R. Li*M. Liang*K. Liepmann*S. LongoR. Low*M.-H. Lu*J. MarellaJ. Marsh*P. McCarthyG. McKeeD. Miletich*M. Minarczyk*Z. Mooney*M. Nadal*D. Nava*D. OHare*Y. Ohno*J. Pan*D. Park*N. Peimanovic*E. Perkins*M. Piscitelli*G.

15、Plank*E. RadkovD. Randolph*C. Richards*E. Richman*D.Rogers*M. SapcoeA. Serres*A. SmithR. Speck*L. Stafford*G. SteinbergW. Sun*L. Swainston*R. Taylor*K. Tracy*R. Tuttle*T. Uchida*J. Vollers*K. Wagner*J. Walker*Y. Wang*H. Waugh*D. Weiss*J. Welch*K. Wilcox*V. Wu*J. Yo nR. Young*J. Zhang*Y. Zong* Adviso

16、ry*HonoraryPlease refer to the IES Bookstore after you purchase this IES Standard, for possible Errata, Addenda, and Clarifications: www.ies.org/bookstoreContentsFOREWORD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

17、 . . . . . . . . . . 1INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.0 SCOPE 12.0 NORMATIVE REFERENCES . 13.0 NOMENCLATURE AND DEFINITIONS . 13.1 Total Luminous Flux . 13.2 Sphere Efficacy

18、 . 13.3 Sphere Responsivity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24.0 PHYSICAL AND ENVIRONMENTAL TEST CONDITIONS 25.0 INTEGRATING SPHERE EQUIPMENT . 25.1 Integrating Sphere Geormetry: 4. . . . . . . . . . . . . . . . . .

19、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25.2 Integrating Sphere Geormetry: 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35.3 Sphere Coating . 35.4 Baffle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

20、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55.5 Auxiliary Lamp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55.6 Photometer Detection 65.7 Spectroradiometer Detection . . . . . . . . . . . . .

21、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75.8 Lamp Holder and Mounting Hardware 75.9 Temperature Sensor . 85.10 Electrical Circuits . 86.0 CALIBRATION STANDARDS 86.1 Incandescent Standard Lamps 86.2 Incandescent Reflector Lamps 86.3 Discharge Standard Lamps . 96

22、.4 Solid-State Lighting Standard Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96.5 Handling of Standards Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96.6 Operation of Standard Lamps . 97

23、.0 TEST PROCEDURES . 107.1 Total Luminous and Total Spectral Spectral Radiant Flux Calibration . 107.1.1 Integrating Sphere with Photometer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107.1.2 Integrating Sphere with Spectroradiometer 107.2 Test Lamp Measurement

24、 Procedure . 107.2.1 Integrating Sphere with Photometer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107.2.2 Integrating Sphere with SpectroRadiometer . 117.3 Sources of Error 117.3.1 Self-Absorption. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

25、 . . . . . . . . . . . . . . . . . . . . . . . . . . 117.3.2 Spectral Mismatch . 127.3.3 Sphere Angular Non-uniformity . 137.3.4 Near-Field Absorption 137.3.4 Temperature Effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138.0 UNCERTA

26、INTY EVALUATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149.0 MAINTENANCE OF INTEGRATING SPHERES . 14INFORMATIVE REFERENCES . 15ANNEX A BASIC INTEGRATING SPHERE THEORY 15ANNEX B MEASUREMENT OF THE RELATIVE SPECTRAL THROUGHPUT OF A

27、N INTEGRATING SPHERE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17ANNEX C CORRECTION FOR THE ANGULAR NON-UNIFORMITY ERRORS OF AN INTEGRATING SPHERE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18ANNEX D ALTERNATIVE GEOMETRIES AND CALIBRATION METHODS. .

28、 . . . . . . . . . . . . . . . . . . . . . 181IES LM-78-17FOREWORDThis document is one of a continuing series of IES Approved Methods prepared to define a baseline for acceptable photometric procedures leading to improved agreement among laboratories. This Approved Method document explains a particu

29、lar technique for total flux measurement of all types of lamps and luminaires using integrating spheres. The main improvement in this document compared to IES LM-78-2007 is the addition of spectral measurements. While most statements are written using lamp, they apply to lamps and luminaires.INTRODU

30、CTIONTotal luminous flux is the angularly integrated, photopically weighted, total light output from a lamp. Total luminous flux is one of the most important parameters for non-directional, general lighting products. While luminous intensity and beam angle are typically more important for directiona

31、l lamps, such as reflector lamps, and luminaires, total luminous flux is still an important quantity. Regulations are usually based on luminous efficacy (lm/W), which is the total luminous flux divided by the electrical input power of the light-emitting device. This document describes techniques for

32、 measuring the total flux of lamps and luminaires. One method is exclusive to total luminous flux measurements: an integrating sphere system using a photometer. The second method described, an integrating sphere system using a spectroradiometer, is used to measure a variety of angularly integrated q

33、uantities. The integrating sphere system has the advantage of fast measurements and does not require a dark room. Air movement is minimized and temperature within the sphere is not subject to the fluctuations potentially present in a temperature-controlled room. The approved method is based on the c

34、omparison of the total luminous flux or total spectral radiant flux of a test lamp or luminaire to the total luminous flux or total spectral radiant flux of a standard lamp in an integrating sphere system. While photometric and spectral integrating sphere measurement systems are very similar, they e

35、ach have positive and negative aspects. Photometric measurement systems use a V()-corrected photometer head, which suffers from spectral mismatch errors. Spectral mismatch errors occur because relative spectral responsivity of the integrating sphere photometric system deviates from the V() function.

36、 The spectral integrating sphere measurement system does not have spectral mismatch errors. Spectral integrating sphere measurement systems are capable of measuring the integrated color quantities of a light-emitting device; however, they are susceptible to spectral stray light and stability concern

37、s. The two measurement techniques are compared and contrasted in this document along with the techniques required to make high quality measurements.1.0 SCOPEThis approved method describes the procedures to be followed and precautions to be observed in performing reproducible measurements of total fl

38、ux of lamps and luminaires using integrating sphere measurement systems. Two types of integrating sphere systems are presented, one employing a V()-corrected photometer head, and another employing a spectroradiometer as the detector. In addition to the specifics of the two measurement systems, the c

39、ommon qualities and measurement techniques are discussed along with calibration and uncertainty analysis considerations.2.0 NORMATIVE REFERENCESIES. ANSI/IES RP-16-17. Nomenclature and Definitions for Illuminating Engineering. New York: Illuminating Engineering Society; 2017.3.0 NOMENCLATURE AND DEF

40、INITIONS3.1 Total Luminous Flux While the luminous flux (v) is defined in the International Lighting Vocabulary (ILV; CIE 2011) as the quantity derived from the radiant flux, eby evaluating the radiation according to its action upon the CIE standard photometric observer, the total luminous flux is t

41、he cumulative luminous flux of a light emitting device over the solid angle of 4 sr. The total luminous flux is often called “luminous flux” in photometry practice. The unit of total luminous flux is the lumen. 3.2 Sphere Efficacy Sphere efficacy (Ed/v) is the ratio of the illuminance Edat the detec

42、tor port to the total luminous flux vof a light emitting device in the sphere, in units of 1/m2. 2IES LM-78-173.3 Sphere Responsivity The sphere responsivity (yd/v) of the system is the ratio of the photometer signal ydto the total luminous flux vof a light emitting device in the sphere. 4.0 PHYSICA

43、L AND ENVIRONMENTAL TEST CONDITIONSThe integrating sphere efficacy can be slightly affected by changes in temperature or humidity. The responsivity of the photometer head on the integrating sphere is also affected by changes of temperature (typically approximately 0.1 percent per degree Celsius of c

44、hange). Further integrating sphere efficacy is affected by dust and particulates that accumulate on the integrating sphere coating. Thus, it is preferred to place the integrating sphere in a clean, reasonably temperature-controlled environment. For lighting devices that emit a significant amount of

45、heat, the integrating sphere may be slightly ajar during the stabilization time. Once the lighting device is stabilized, the sphere should be closed and the measurements made as quickly as possible.The ambient conditions are more critical for measurements of particular types of discharge lamps and s

46、olid-state lighting products. For example, fluorescent lamps are required to be operated in an ambient temperature of 25 C 1 C. (Refer to the appropriate LM document for the required ambient conditions for each lamp type to be measured.)5.0 INTEGRATING SPHERE EQUIPMENT5.1 Integrating Sphere Geometry

47、: 4Figure 1 shows the geometry of a typical integrating sphere system for total flux measurements where the test lamp is mounted in the center of the sphere and the light output is measured in all directions (4 steradians, sr). The integrating sphere is equipped with a photometer head or spectroradi

48、ometer, a baffle, an auxiliary lamp assembly, a diffusely reflective sphere coating, lamp mounting hardware, lamp holder and associated electrical wiring. The optimum size of the sphere should be chosen by considering the following factors:A. Size of the Lamp (thus, required size of the baffle)B. Se

49、lf-absorption of the lamp, lamp holder and lamp mounting hardware (see Section 7.3.1)C. Internal sphere temperatureD. Sphere responsivity (lowest measurable total flux)Factors A, B, and C drive the sphere to be as large as possible, while factor D limits the sphere size. Factors B and D are affected by the chosen reflectivity of the sphere coating. In the 4 geometry, as a guideline, the total surface area of the lamp should be less than 2 percent of the total area of the sphere wall.aA general rule is to have the sphere diameter larger than 10 times the lar