1、BRITISH STANDARD BS EN 61315:2006 Calibration of fibre-optic power meters The European Standard EN 61315:2006 has the status of a British Standard ICS 33.140; 33.180.10 BS EN 61315:2006 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 6 March
2、2006 BSI 6 March 2006 ISBN 0 580 47924 2 National foreword This British Standard is the official English language version of EN 61315:2006. It is identical with IEC 61315:2005. It supersedes BS EN 61315:1997 which is withdrawn. The UK participation in its preparation was entrusted to Technical Commi
3、ttee GEL/86, Fibre optics, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in th
4、e BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible
5、for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK inter
6、ests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 42, an inside back cover and a back cover. The BSI copyright notice displayed in this doc
7、ument indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments EUROPEAN STANDARD EN 61315 NORME EUROPENNE EUROPISCHE NORM January 2006 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europi
8、sches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2006 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 61315:2006 E ICS 33.140;33.180.10 Supersedes EN 61315:1997English version C
9、alibration of fibre-optic power meters (IEC 61315:2005) Etalonnage de wattmtres pour dispositifs fibres optiques (CEI 61315:2005) Kalibrierung von Lichtwellenleiter- Leistungsmessern (IEC 61315:2005) This European Standard was approved by CENELEC on 2005-11-01. CENELEC members are bound to comply wi
10、th the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretar
11、iat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the
12、official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Sl
13、ovenia, Spain, Sweden, Switzerland and United Kingdom. 2 Foreword The text of document 86/239/FDIS, future edition 2 of IEC 61315, prepared by IEC TC 86, Fibre optics, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61315 on 2005-11-01. This European Standard superse
14、des EN 61315:1997. Changes from EN 61315:1997 consist of adapting the uncertainty calculations to the approach taken by the GUM, and adapting the terminology and graphical symbology to international standards VIM, IEC 61931 and IEC 61930. The importance of the nonlinearity calibration is emphasized
15、by giving more detail and is now in a separate clause. Requirements concerning organization and traceability have been taken out of this standard since they are general requirements concerning calibration laboratories and are given in EN ISO/IEC 17025. The goal to standardize the type of power meter
16、 specifications has been removed since it does not belong in a standard on calibration. Specifications should, however, still be based on calibrations made following this standard and EN 60359. The following dates were fixed: latest date by which the EN has to be implemented at national level by pub
17、lication of an identical national standard or by endorsement (dop) 2006-08-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2008-11-01 _ Endorsement notice The text of the International Standard IEC 61315:2005 was approved by CENELEC as a European Sta
18、ndard without any modification. _ EN 61315:2006 3 EN 61315:2006 CONTENTS INTRODUCTION 4 1 Scope 5 2 Normative references .5 3 Terms and definitions .6 4 Preparation for calibration 13 4.1 Organization13 4.2 Traceability .13 4.3 Advice for measurements and calibrations .14 4.4 Recommendations to cust
19、omers 15 5 Absolute power calibration15 5.1 Establishing the calibration conditions .16 5.2 Calibration procedure 17 5.3 Calibration uncertainty.18 5.4 Reporting the results .25 6 Measurement uncertainty of a calibrated power meter.25 6.1 Uncertainty at reference conditions25 6.2 Uncertainty at oper
20、ating conditions26 7 Nonlinearity calibration.33 7.1 Nonlinearity calibration based on superposition .34 7.2 Nonlinearity calibration based on comparison with a calibrated power meter 36 7.3 Nonlinearity calibration based on comparison with an attenuator37 7.4 Calibration of power meter for high pow
21、er measurement 37 Annex A (normative) Mathematical basis39 A.1 Type A evaluation of uncertainty39 A.2 Type B evaluation of uncertainty39 A.3 Determining the combined standard uncertainty.40 A.4 Reporting 41 Figure 1 Typical spectral responsivity of photoelectric detectors.11 Figure 2 Example of a tr
22、aceability chain.13 Figure 3 Measurement setup for sequential, fibre-based calibration16 Figure 4 Change of conditions and uncertainty.21 Figure 5 Determining and recording an extension uncertainty.27 Figure 6 Possible subdivision of the optical reference plane into 10 x 10 squares, for the measurem
23、ent of the spatial response.28 Figure 7 Wavelength dependence of response due to Fabry-Perot type interference.32 Figure 8 Measurement setup of polarization dependent response.32 Figure 9 Nonlinearity calibration based on superposition 34 Figure 10 Measurement setup for nonlinearity calibration by c
24、omparison36 Table 1 Typical calibration methods and correspondent power .15 Table 2 Nonlinearity.35EN 61315:2006 4 INTRODUCTION Fibre-optic power meters are designed to measure optical power from fibre-optic sources as accurately as possible. This capability depends largely on the quality of the cal
25、ibration process. In contrast to other types of measuring equipment, the measurement results of fibre- optic power meters usually depend on many conditions of measurement. The conditions of measurement during the calibration process are called calibration conditions. Their precise description must t
26、herefore be an integral part of the calibration. This International Standard defines all of the steps involved in the calibration process: establishing the calibration conditions, carrying out the calibration, calculating the uncertainty, and reporting the uncertainty, the calibration conditions and
27、 the traceability. The absolute power calibration describes how to determine the ratio between the value of the input power and the power meters result. This ratio is called correction factor. The measurement uncertainty of the correction factor is combined following Annex A from uncertainty contrib
28、utions from the reference meter, the test meter, the setup and the procedure. The calculations go through detailed characterizations of individual uncertainties. It is important to know that: a) estimations of the individual uncertainties are acceptable; b) a detailed uncertainty analysis is only ne
29、cessary once for each power meter type under test, and all subsequent calibrations can be based on this one-time analysis, using the appropriate type A measurement contributions evaluated at the time of the calibration; c) some of the individual uncertainties can simply be considered to be part of a
30、 checklist, with an actual value which can be neglected. Calibration according to Clause 5 is mandatory for reports referring to this standard. Clause 6 describes the evaluation of the measurement uncertainty of a calibrated power meter operated within reference conditions or within operating condit
31、ions. It depends on the calibration uncertainty of the power meter as calculated in 5.3, the conditions and its dependence on the conditions. It is usually performed by manufacturers in order to establish specifications and is not mandatory for reports referring to this standard. One of these depend
32、ences, the nonlinearity, is determined in a separate calibration (Clause 7). NOTE Fibre-optic power meters measure and indicate the optical power in the air, at the end of an optical fibre. It is about 3,6 % lower than in the fibre due to Fresnel reflection at the glass-air boundary (with N = 1,47).
33、 This should be kept in mind when the power in the fibre has to be known. 5 EN 61315:2006 CALIBRATION OF FIBRE-OPTIC POWER METERS 1 Scope This international standard is applicable to instruments measuring radiant power emitted from sources which are typical for the fibre-optic communications industr
34、y. These sources include laser diodes, light emitting diodes (LEDs) and fibre-type sources. The radiation may be divergent or collimated. The standard describes the calibration of power meters to be performed by calibration laboratories or by power meter manufacturers. 2 Normative references The fol
35、lowing referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60050-300, International Electrotechnical Vocabulary
36、 Electrical and electronic measurements and measuring instruments Part 311: General terms relating to measurements Part 312: General terms relating to electrical measurements Part 313: Types of electrical measuring instruments Part 314: Specific terms according to the type of instrument IEC 60359, E
37、lectrical and electronic measurement equipment Expression of performance IEC 60793-2, Optical fibres Part 2: Product specifications General IEC 61300-3-12, Fibre optic interconnecting devices and passive components Basic test and measurement procedures Part 3-12: Examinations and measurements Polari
38、zation dependence of attenuation of a single-mode fibre optic component: Matrix calculation method IEC 61930, Fibre optic graphical symbology IEC 61931, Fibre optic Terminology ISO/IEC 17025, General requirements for the competence of testing and calibration laboratories BIPM, IEC, IFCC, ISO, IUPAC,
39、 IUPAP, and OIML:1993, International vocabulary of basic terms in metrology (VIM) BIPM, IEC, IFCC, ISO, IUPAC, IUPAP, and OIML:1995, Guide to the expression of uncertainty in measurement (GUM)EN 61315:2006 6 3 Terms and definitions For the purposes of this International Standard, the definitions con
40、tained in IEC 61931 and the following definitions apply. 3.1 accredited calibration laboratory a calibration laboratory authorized by the appropriate national organization to issue calibration certificates with a minimum specified uncertainty, which demonstrate traceability to national standards 3.2
41、 adjustment set of operations carried out on an instrument in order that it provides given indications corresponding to given values of the measurand IEV 311-03-16; see also VIM 4.30 NOTE When the instrument is made to give a null indication corresponding to a null value of the measurand, the set of
42、 operations is called zero adjustment 3.3 calibration set of operations that establish, under specified conditions, the relationship between the values of quantities indicated by a measuring instrument and the corresponding values realized by standards VIM, 6.11, modified NOTE 1 The result of a cali
43、bration permits either the assignment of values of measurands to the indications or the determination of corrections with respect to indications. NOTE 2 A calibration may also determine other metrological properties such as the effect of influence quantities. NOTE 3 The result of a calibration may b
44、e recorded in a document, sometimes called a calibration certificate or a calibration report. 3.4 calibration conditions conditions of measurement in which the calibration is performed 3.5 centre wavelength centre the power-weighted mean wavelength of a light source in vacuum. For a continuous spect
45、rum the centre wavelength is defined as: centre = d p P ) ( 1 total and the total power is: P total= d p ) ( where p( ) is the power spectral density of the source, for example in W/nm. 7 EN 61315:2006 For a spectrum consisting of discrete lines, the centre wavelength is defined as: centre = i i i P
46、 P where P i is the power of the i thdiscrete line, for example in W, and i is the vacuum wavelength of the i thdiscrete line. NOTE The above integrals and summations theoretically extend over the entire spectrum of the light source, however it is usually sufficient to perform the integral or summat
47、ion over the spectrum where the spectral density p( ) or power P i is higher than 0,1 % of the maximum spectral density p( ) or power P i . 3.6 correction factor CF numerical factor by which the uncorrected result of a measurement is multiplied to compensate for systematic error VIM, 3.16 3.7 decibe
48、l dB submultiple of the bel (1 dB = 0,1 B), unit used to express values of power level on a logarithmic scale. The power level is always relative to a reference power P 0 : 0 10 / log 10 0 P P L P P(dB) where P and P 0are expressed in the same linear units. The reference power must always be reporte
49、d, for example, the power level of 200 W relative to 1 mW can be noted L P/1 mW= 7 dB or L P (re 1 mW) = 7 dB. The linear ratio, R lin , of two radiant powers, P 1and P 2 , can alternatively be expressed as a power level difference in decibels (dB): L P= 10 log 10 (R lin ) = 10 log 10 (P 1 /P 2 ) = 10 log 10
