1、IES LM-77-09Approved Method: Intensity Distribution of Luminaires and Lamps Using Digital Screen Imaging PhotographyIES LM-77-09IES Approved MethodforIntensity Distribution Measurementof Luminaires and Lamps Using Digital Screen Imaging PhotometryPublication of this report has been approved by IES.S
2、uggestions for revisions should be directed to IESPrepared by: The Digital Photometry Task Forceof the IES Testing Procedures CommitteeIES LM-77-09Copyright 2009 by the Illuminating Engineering Society of North America.Approved by the IES Board of Directors, November 15, 2009, as a Transaction of th
3、e Illuminating Engineering Society of North America.All rights reserved. No part of this publication may be reproduced in any form, in any electronic retrieval system or otherwise, without prior written permission of the IES.Published by the Illuminating Engineering Society of North America, 120 Wal
4、l 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. If any errors are noted in this document, please forward them to Rita Harrold, Director Educational and
5、Technical Development, at the above address for verifi-cation and correction. The IES welcomes and urges feedback and comments. ISBN # 978-0-87995-237-2Printed in the United States of America.DISCLAIMERIES publications are developed through the consensus standards development process approved by the
6、 American National Standards Institute. This process brings together volunteers represent-ing varied viewpoints and interests to achieve consensus on lighting recommendations. While the IES administers the process and establishes policies and procedures to promote fairness in the development of cons
7、ensus, 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 nature whatsoever, whether special, indirect, consequential or compensatory, directly or indirectl
8、y result-ing 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 any person or entity. Nor is the IES undertaking to perform any duty owed by any person or ent
9、ity 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 care in any given circumstances.The IES has no power, nor does it undertake, to police or enfor
10、ce 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 compliance with the requirements of this document shall not be attributable to the IES and is sol
11、ely the responsibility of the certifier or maker of the statement.IES LM-77-09Prepared by the Digital Photometry Task Force of the IES Testing Procedures CommitteeTask ForceI. Lewin, ChairI. AshdownK.F. LinJ.K. OFarrellIES Testing Procedures CommitteeMichael Grather, ChairC. K. AndersenD. V. Andreye
12、v*J. B. Arens L. M. AyersW.E. BeakesR. C. BergerR. P. Bergin*R. S. BergmanJ. R. Cyre*R. C. Dahl*R. O. Daubach*K. J. DowlingD. EllisA.M. Foy*P. J. Franck*R. V. HeinischT. T. Hernandez*R. E. HoranD. E. Husby*J. Hospodarsky*J. Jiao*M. A. KalkasD. Karambelas M. KotrebaiK.K. KruegerB. Kuebler*E. Ladouceu
13、r*J. Lawton*L. E. Leetzow*K. C. Lerbs*R. E. Levin*I. LewinR. Low*J. P. MarellaG. McKeeS. W. McKnight*D. C. Mertz*C. C. MillerB. MosherW. A. NewlandY. Ohno*D. W. Parkansky*D. N. Randolph D. RectorM. B. SapcoeD. C. Smith*R. C. Speck*L. Stafford*G. A. SteinbergN. Stuffer*T. G. Yahraus*J. X. Zhang* Advi
14、sory Member* Honorary MemberIES LM-77-09IES LM-77-09Contents1.0 Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.0 Background and Basic Principles . . . . . . . . . . . . . . . . . .
15、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.1 Noise in CCD Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33.0 Test system geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
16、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44.0 Angular Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55.0 Stray Light . . . . . . . . . . . . . . . . . . . . . . . .
17、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56.0 Specification of the Digital Camera . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66.1 Still versus Video Cameras . . . . . . .
18、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66.2 CCD Chip Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66.3 Shutters . . . . . . . . . . . . . . . . .
19、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66.4 Data Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76.5 Dynamic Range . . . . . . .
20、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76.6 CCD Grade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86.7 Camera Controls . . .
21、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86.8 Camera Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86.9 Lens Selection . .
22、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86.10 Spectral Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96.11 Neutral Den
23、sity Filters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97.0 Linearity Verification and Useable Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97.1 Dark Field Cor
24、rection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107.2 Response versus Luminance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107.3 Response versus Exposure Tim
25、e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117.4 Defective Pixels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128.0 Calibration . . . . . . . . . . . . . .
26、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128.1 Lens Distortion Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128.2 Geometric Calibration . .
27、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128.3 Absolute Intensity Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138.4 Calibration Correction for Exposure
28、 Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148.5 Relative Intensity Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149.0 Test Procedure . . . . . . . . . . . . . . . . . . . . .
29、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1410.0 Data Reduction and test report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15References . . . . . . . . . . . . . . . . .
30、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
31、ANNEX AGeometrical Relationships . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19A1 Pixel Rows And Columns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19A2 Re
32、lating Screen Locations and Photometric Angles Type B Coordinates . . . . . . . . . . . . . . . . . . . 20IES LM-77-09A3 Relating Screen Geometry to Pixel Row and Column. (Type B Coordinates) . . . . . . . . . . . . . . . . . . 20A3.1 Determining the Pixel Row for a Given Vertical Photometric Angle.
33、 (Type B Coordinates) . 21A3.2 Determining the Pixel Column for Given Photometric Angles. (Type B Coordinates) . . . . . . 22A3.3 Determining Photometric Angles for a Given Pixel. (Type B Coordinates) . . . . . . . . . . . . . . . 23A3.3.1 Vertical Photometric Angle . . . . . . . . . . . . . . . . .
34、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23A3.3.2 Horizontal Photometric Angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23A4 Use of a Type A Coordinate System . . . . . . . . . . . . . . . . . . . . . . . . . . . .
35、. . . . . . . . . . . . . . . . . . . . . . . . . 24A4.1 Relating Screen Locations and Photometric Angles. (Type A Coordinates) . . . . . . . . . . . . . . 24A4.2 Relating Screen Geometry to Pixel Row and Column. (Type A Coordinates) . . . . . . . . . . . . . 25A4.3 Determining Photometric angles fo
36、r a Given Pixel. (Type A Coordinates) . . . . . . . . . . . . . . . 25A5 Use of a Type C Coordinate System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25A5.1 Relating Screen Locations and Photometric Angles. (Type C Coordinates) . . . . .
37、 . . . . . . . . . 25A5.2 Relating Screen Geometry to Pixel Row and Column. (Type C Coordinates) . . . . . . . . . . . . . 26A5.3 Determining Photometric Angles for a Given Pixel. (Type C Coordinates) . . . . . . . . . . . . . . . 26A6 Use of a Modified Type C Coordinate System . . . . . . . . . . .
38、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26A6.1 Relating Screen Locations and Photometric Angles. (Modified Type C Coordinates) . . . . . . 27A6.2 Relating Screen Geometry to Pixel Row and Column. (Modified C Coordinates) . . . . . . . . . . 27A6.3 Determining Photometric
39、 Angles for a Given Pixel. (Modified Type C Coordinates) . . . . . . . 28A7 Determination of Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
40、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28ANNEX BLens Distortion Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29B1 Basic Principles . . . . . . . . . . . . . . . . . . . .
41、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29B2 Data Collection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29B2.1 Center Pixel Determination . .
42、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29B2.2 Measurement Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29B3 Data Reduction . . . . . . . . . . . . . .
43、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30B3.1 Actual Pixel Positions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30B3.2 Computed Pixel Positions . . .
44、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30B3.3 Curve Fit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30ANNEX CNoise Estimation . . . .
45、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31ANNEX DLinearity Calculation Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 321IES LM-77-09IES Approved Method fo
46、r Intensity Distribution Measurement of Luminaires and Lamps Using Digital Screen Imaging Photometry1.0 FOREWORDThe intent of this IES document is to describe mea-surement procedures for the determination of the luminous intensity distribution of certain lamps and luminaires using a digital camera t
47、o capture the pro-jected light distribution from a luminaire on a screen. Because this is a relatively new technique, consider-able detail is provided to assist the reader in under-standing the principles, requirements and limitations involved. As more experience is gained and as digital cameras inc
48、rease in their capabilities, further requirements are likely to be developed. At this stage of development, digital photometry offers very high speed data collection versus a traditional goniopho-tometer, although typically over a restricted angular range. Many factors must be taken into account to
49、achieve accurate digital photometry; this report addresses the most significant of these factors.Other uses of cameras to perform digital photometry, such as capturing the distribution of a luminaire by aiming the camera at the luminaire, close field pho-tometry techniques and methods using integrating spheres, are outside the scope of this report.2.0 BACkGROUND AND BASIC PRINCIPLESThe measurement of luminaire intensity distributions and associated quantities has traditionally been performed using some form of goniophotometer. Such instruments may use a ro
