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Optical Radiation Measurements: the Impact of Radiometry And v HI IS - %. Ml . I 1 ( 9^ I Sin MtSI MB Hwr SEraB X' -. 1 I I I >* i - ' I I (Srf 1 1I ^miS H HI - 1 H • 1 1 h 1Up NBS TECHNICAL NOTE 594-4 Optical Radiation Measurements: The Impact of Radiometry and Photometry and the Role of NBS NATIONAL BUREAU OF STANDARDS The National 1 Bureau of Standards was established by an act of Congress March 3, 1 901 The Bureau's overall is . goal to strengthen and advance the Nation's science and technology and facilitate their effective application for public benefit. To this end, the Bureau conducts research and provides: (1) a basis for the Nation's physical measure- ment system, (2) scientific and technological services for industry and government, (3) a technical basis for equity in trade, and (4) technical services to promote public safety. The Bureau consists of the Institute for Basic Standards, the Institute for Materials Research, the Institute for Applied Technology, the Center for Computer Sciences and Technology, and the Office for Information Programs. THE INSTITUTE FOR BASIC STANDARDS provides the central basis within the United States of a complete and consistent system of physical measurement; coordinates that system with measurement systems of other nations; and furnishes essential services leading to accurate and uniform physical measurements throughout the Nation's scien- tific community, industry, and commerce. The Institute consists of a Center for Radia- tion Research, an Office of Measurement Services and the following divisions: Applied Mathematics — Electricity — Mechanics — Heat — Optical Physics — Linac Radiation °- — Nuclear Radiation L> — Applied Radiation - — Quantum Electronics :: — Electromagnetics :i — Time and Frequency 3 — Laboratory :: 3 Astrophysics — Cryogenics . THE INSTITUTE FOR MATERIALS RESEARCH conducts materials research lead- ing to improved methods of measurement, standards, and data on the properties of well-characterized materials needed by industry, commerce, educational institutions, and Government; provides advisory and research services to other Government agencies; and develops, produces, and distributes standard reference materials. The Institute con- sists of the Office of Standard Reference Materials and the following divisions: Analytical Chemistry—Polymers—Metallurgy—Inorganic Materials—Reactor Radiation—Physical Chemistry. THE INSTITUTE FOR APPLIED TECHNOLOGY provides technical services to pro- mote the use of available technology and to facilitate technological innovation in indus- try and Government; cooperates with public and private organizations leading to the development of technological standards (including mandatory safety standards), codes and methods of test; and provides technical advice and services to Government agencies upon request. The Institute also monitors NBS engineering standards activities and provides liaison between NBS and national and international engineering standards bodies. The Institute consists of a Center for Building Technology and the following divisions and offices: Engineering and Product Standards—Weights and Measures—Invention and Innovation—Product Evaluation Technology—Electronic Technology—Techni- cal Analysis—Measurement Engineering—Building Standards and Code Serv- ices 4—Housing Technology 4 —Federal Building Technology 4—Structures, Mate- rials and Life Safety 4—Building Environment 4—Technical Evaluation and Application 4 —Fire Technology. THE INSTITUTE FOR COMPUTER SCIENCES AND TECHNOLOGY conducts re- search and provides technical services designed to aid Government agencies in improv- ing cost effectiveness in the conduct of their programs through the selection, acquisition, and effective utilization of automatic data processing equipment; and serves as the prin- cipal focus within the executive branch for the development of Federal standards for automatic data processing equipment, techniques, and computer languages. The Center consists of the following offices and divisions: Information Processing Standards—Computer Information—Computer Services —Systems Development—Information Processing Technology. THE OFFICE FOR INFORMATION PROGRAMS promotes optimum dissemination and accessibility of scientific information generated within NBS and other agencies of the Federal Government; promotes the development of the National Standard Reference Data System and a system of information analysis centers dealing with the broader aspects of the National Measurement System; provides appropriate services to ensure that the NBS staff has optimum accessibility to the scientific information of the world, and directs the public information activities of the Bureau. The Office consists of the following organizational units: Office of Standard Reference Data—Office of Technical Information and Publications—Library—Office of International Relations. 1 mailing address Headquarters and Laboratories at Gaithersburg, Maryland, unless otherwise noted ; Washington, D.C. 20234. 2 Part of the Center for Radiation Research. 3 Located at Boulder, Colorado 80302. 4 Part of the Center for Building Technology. Optical Radiation Measurements: The Impact of Radiometry and Photometry and the Role of NBS Bruce Steiner Heat Division Institute for Basic Standards National Bureau of Standards Washington, D.C. 20234 <f WW \ &.';, U.S. DEPARTMENT OF COMMERCE, Frederick B. Dent, Secretary NATIONAL BUREAU OF STANDARDS, Richard W. Roberts, Director Issued March 1973 National Bureau of Standards Technical Note 594-4 Nat. Bur. Stand. (U.S.), Tech. Note 5944, 56 pages (Mar. 1973) CODEN: NBTNAE For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. Price $0.80 domestic postpaid or $0.55G.P.O. Bookstore. Preface This is the fourth issue of a series of Technical Notes entitled OPTICAL RADIATION MEASUREMENTS. The series consists primarily of reports of progress in or details of research conducted in radiometry and photometry in the Optical Radiation Section of the Heat Division and appears about every six weeks. The current issue, however, is an exception. It presents the impact of radiometry and photometry on a number of problems of national concern and NBS' role in the measurement aspects of these problems. The document was originally prepared for internal use. It is being included in this series because of the belief that it would be of interest and use to a much wider audience. Henry J. Kostkowski , Chief Optical Radiation Section National Bureau of Standards 111 . Foreword Individual scientists and scientific institutions are "being asked increasingly to identify specific long-term effects of their work. This identification is at best difficult and imprecise. Nevertheless it provides as quantitative a "basis as is possible for establishing specific programs and priorities. This examination of potential effectiveness has been stimulated by the increased concern for national problems, such as the energy crisis, pollution, and public safety. In the development of solutions for these problems, the suitability of technical approaches must be assessed. The promise of specific experimental and theoretical procedures must be evaluated. Thus increasingly the relationship of various technical fields to national goals and problems must be identified. One technical area of major potential impact on many problems of national concern is the field of electro-optics. This field has experienced exceptionally rapid growth in the last five years. Though this growth has strengthened markedly the ability of the field to provide solutions to certain problems, it has created its own problems in terms of increased disagreements among measurements. Disagreements in optical radiation measure- ments of commercial and public significance are now widely evident and are growing in severity. Therefore the National Bureau of Standards is now reviewing its traditional concern for optical radiation measurement accuracy, the new emphasis on national needs, and the application of sophisticated technical measurement to national problems. Its review of these national questions, the answers to which depend on progress in optical radiation measurement, may interest a wider audience than the Department of Commerce, for which this report was initially prepared. The study is designed not only to describe present important problems but to con- centrate on those of future impact. It must therefore anticipate the development of technology and its problems. It must extrapolate. Therefore this review presents only a cursory summary of many complex issues and some supporting evidence. Commercial questions are also intimately involved. Any improvement in industrial technology stems from and in turn will stimulate keen competitive interest. We are indeed extremely grateful to our correspondents in industry, especially those in the Council for Optical Radiation Measurement, for the insights that they have given us. But because of the commercial impact of technical forecasting in this area, this version of the NBS study excludes individual reference to particular companies and the exact data they have given us A comprehensive study of the issues might well be expected to include a detailed program for action. In Chapter 5 some general comments are made that suggest such a program. Detailed programs have in fact been constructed separately in the various projects covering areas of this review. A comprehensive, centralized solution has not been proposed here. Nevertheless one initial component in a new NBS approach to these problem-studded
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