1、BRITISH STANDARDBS EN 60793-1-34: 2006Optical fibres Part 1-34: Measurement methods and test procedures Fibre curlThe European Standard EN 60793-1-34:2006 has the status of a British StandardICS 33.180.10g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g
2、3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN 60793-1-34:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 29 September 2006 BSI 2006ISBN 0 580 49281 8National forewordThis Bri
3、tish Standard was published by BSI. It is the UK implementation of EN 60793-1-34:2006. It is identical with IEC 60793-1-34:2006. It supersedes BS EN 60793-1-34:2002 which is withdrawn. The UK participation in its preparation was entrusted by Technical Committee GEL/86, Fibre optics, to Subcommittee
4、GEL/86/1, Optical fibres and cables.A list of organizations represented on GEL/86/1 can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standar
5、d cannot confer immunity from legal obligations.Amendments issued since publicationAmd. No. Date CommentsEUROPEAN STANDARD EN 60793-1-34 NORME EUROPENNE EUROPISCHE NORM June 2006 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisch
6、es 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 60793-1-34:2006 E ICS 33.180.10 Supersedes EN 60793-1-34:2002English version O
7、ptical fibres - Part 1-34: Measurement methods and test procedures - Fibre curl (IEC 60793-1-34:2006) Fibres optiques - Partie 1-34: Mthodes de mesure et procdures dessai - Ondulation de la fibre (CEI 60793-1-34:2006) Lichtwellenleiter -Teil 1-34: Messmethoden und Prfverfahren - Faserringeln (IEC 60
8、793-1-34:2006) This European Standard was approved by CENELEC on 2006-04-01. CENELEC members are bound to comply with 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 b
9、ibliographical references concerning such national standards may be obtained on application to the Central Secretariat 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 responsib
10、ility of a CENELEC member into its own language and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hung
11、ary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Foreword The text of document 86A/1049/FDIS, future edition 2 of IEC 60793-1-34, prepared by SC 86A, Fibres a
12、nd cables, of IEC TC 86, Fibre optics, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60793-1-34 on 2006-04-01. This European Standard supersedes EN 60793-1-34:2002. It provides more details for performing the described test. The following dates were fixed: latest d
13、ate by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2007-01-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2009-04-01 Annex ZA has been added by CENELEC. _ Endorsement
14、notice The text of the International Standard IEC 60793-1-34:2006 was approved by CENELEC as a European Standard without any modification. _ EN 60793-1-34:2006 2 3 EN 60793-1-34:2006 CONTENTS 1 Scope 4 2 Normative references .4 3 Apparatus.4 3.1 Principle4 3.2 Fibre holding fixture.5 3.3 Fibre rotat
15、or 5 3.4 Deflection measurement device .5 3.5 Computer (optional).5 4 Sample preparation 5 5 Procedure 5 5.1 Mounting of the fibre5 5.2 Rotation 5 5.3 Calculation 5 6 Results.6 7 Specification information.6 Annex A (normative) Fibre curl by side view microscopy .7 Annex B (informative) Fibre curl by
16、 laser beam scattering.11 Annex C (informative) Derivation of the circular fiber curl model .13 Annex ZA (normative) Normative references to international publications with their corresponding European publications17 Figure A.1 Schematic diagram for apparatus to measure fibre curl using an optical m
17、icroscope.9 Figure A.2 Schematic diagram for apparatus to measure fibre curl using a laser micrometer .9 Figure A.3 Schematic diagram for apparatus to measure fibre curl while securing the sample in a ferrule10 Figure B.1 Schematic diagram of optical curl by laser beam scattering12 Figure C.1 Geomet
18、rical layout of side view microscopy fibre curl measurement13 Figure C.2 Geometrical layout of laser scattering fibre curl measurement14 EN 60793-1-34:2006 4 OPTICAL FIBRES Part 1-34: Measurement methods and test procedures Fibre curl 1 Scope This part of IEC 60793 establishes uniform requirements f
19、or the mechanical characteristic: fibre curl or latent curvature, in uncoated optical fibres. Fibre curl has been identified as an important parameter for minimizing the splice loss of optical fibres when using passive alignment fusion splicers or active alignment mass fusion splicers. Two methods a
20、re recognized for the measurement of fibre curl, in uncoated optical fibres: method A: side view microscopy; method B: laser beam scattering. Both methods measure the radius of curvature of an uncoated fibre by determining the amount of deflection that occurs as an unsupported fibre end is rotated a
21、bout the fibres axis. Method A uses visual or digital video methods to determine the deflection of the fibre while method B uses a line sensor to measure the maximum deflection of one laser beam relative to a reference laser beam. By measuring the deflection behaviour of the fibre as it is rotated a
22、bout its axis and understanding the geometry of the measuring device, the fibres radius of curvature can be calculated from simple circular models, the derivation of which are given in Annex C. Both methods are applicable to types A1, A2, A3 and B optical fibres as described in the IEC 60793 series.
23、 Method A is the reference test method, used to resolve disputes. 2 Normative references The following 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 docum
24、ent (including any amendments) applies. IEC 60793 (all parts), Optical fibres 3 Apparatus 3.1 Principle An uncoated fibre end is mounted in a rotatable fixture so that the end extends freely into space by an overhang distance which will depend on the measurement device. The overhang distance is typi
25、cally 10 mm to 20 mm. If the measurement device is designed with overhang distances greater than this, care must be taken to avoid excessive degradation due to effects of vibration and gravity. The fibre is rotated and the deviations in the position of the overhang point relative to a reference posi
26、tion are measured to obtain the fibres radius of curvature, rc. 5 EN 60793-1-34:2006 Details pertaining to the two methods are given in the relevant Annex A or B. Common apparatus requirements are given below. 3.2 Fibre holding fixture Provide a fixture that holds the fibre on a constant axis at the
27、 holding position and allows the fibre to be rotated through 360. The fixture may be a v-groove holder such as a vacuum chuck or a fibre ferrule. If a ferrule is used, take care to ensure that the inside diameter is sized closely enough to the fibre diameter to minimize variability in the deflection
28、 measurements. 3.3 Fibre rotator Provide a device to grip and rotate the fibre through 360. The device may be manually operated, or may be driven by a rotational device such as a stepper motor. 3.4 Deflection measurement device Provide a deflection measurement device according to either Annex A or A
29、nnex B. 3.5 Computer (optional) A computer may be used to provide motion control, data collection and computation. 4 Sample preparation Use an uncabled fibre of appropriate length for the instrument design. Remove enough coating from one end to allow mounting in the fibre fixture with the necessary
30、overhang. The fibre should not extend much past the measuring devices required overhang distance since excessive lengths can cause degradation as discussed in Clause 3. 5 Procedure Details for each method are given in Annexes A and B. Common procedures are described below. 5.1 Mounting of the fibre
31、Mount the fibre in the holding fixture so that the stripped end extends into free space with sufficient length to extend up to or beyond the overhang distance. Typical overhang distances range between 10 mm and 20 mm. Attach the other end of the fibre to the fibre rotator. If the overhang distance i
32、s excessive, or the stripped fibre is substantially longer than the required overhang distance, then the measurement may be degraded. 5.2 Rotation Follow the procedure of Annex A or Annex B. 5.3 Calculation Complete the detailed calculation of the fibre curl, rc, using Annex A or Annex B. NOTE Thoug
33、h the intermediate parameters used in the calculations are typically scaled in micrometres, the radius of curvature, rc, is typically re-scaled in units of metres. EN 60793-1-34:2006 6 6 Results 6.1 The following information should be reported for each test: date of the test; fibre identification; f
34、ibre radius of curvature. 6.2 The following information should be available for each test: method used to determine curl; description of the equipment; calibration data. 7 Specification information The detail specification shall specify the following: information to be reported; any deviations to th
35、e procedure that apply; failure or acceptance criteria. 7 EN 60793-1-34:2006 Annex A (normative) Fibre curl by side view microscopy A.1 Principle This procedure measures the radius of curvature of an uncoated fibre by determining the amount of deflection that occurs as an unsupported fibre end is ro
36、tated about the fibres axis. By knowing the amplitude of the deflection of the fibre and the overhang distance from the fibre fixture to the measurement point, the fibres radius of curvature can be calculated from a simple circular model, the derivation of which is given in Clause C.1. Schematic dia
37、grams of typical test set-ups for these techniques are shown in Figures A.1, A.2 and A.3. A.2 Apparatus A.2.1 Deflection measurement device Provide a device to measure the fibre deflection as it is rotated through 360. Such a device may consist of a viewing microscope or an optical measuring instrum
38、ent such as a laser micrometer. If a viewing microscope is used, provide means to permit accurate measurement of fibre deflection, such as a filar eyepiece or a digital image analysis system. A.2.2 Video camera and monitor A video camera and monitor may be used to enhance the viewing system for manu
39、al or automated operation. A.2.3 Digital image analysis system (optional) A digital video analyser may be used to provide more precise location of the deflections than might be obtained by a filar eyepiece. Such a system might include an analogue or digital video camera, a frame grabber and associat
40、ed software for the purpose of locating the fibres position at the overhang distance as the fibre is rotated. A.3 Test procedure A.3.1 General Two techniques are provided for obtaining the deflection, f. The first is an extrema technique that is limited by the precision with which the extremes of th
41、e deflection can be determined. The second is a Fourier fitting method. EN 60793-1-34:2006 8 A.3.2 Procedure for the extrema technique Rotate the specimen until the deflection is at a maximum and record the deflection value, Dmax. Rotate the specimen until the deflection is at a minimum, typically 1
42、80 from the angular position of the maximum, and record the deflection value, Dmin. A.3.3 Procedure for the Fourier fitting technique Record the deflection of the specimen at its initial position, D1, and angular position, 1. Rotate the specimen through 360 (do not duplicate the initial position in
43、the data as the last angular position), stopping at equal angular increments and recording the deflection values at each increment, D2.n, and its angular positions, 2.n. Angular increments of 10 to 30 are typically used. A.4 Calculations A.4.1 Extrema technique calculation The fibre deflection fis c
44、alculated by: 2minmaxfDD = (A.1) where Dmaxand Dminare the maximum and minimum deflection values, generally described in micrometres. A.4.2 Fourier fitting technique calculation Compute the first order Fourier coefficients: =niiiDnI112sin (A.2) =niiiDnR112cos (A.3) Compute fas the magnitude of the f
45、irst-order Fourier component: 2121fIR += (A.4) Least squares fitting of the set of iand Dimay be used as an alternative. The Fourier technique described above and least squares fitting of the amplitude and phase are numerically equivalent. A.4.3 Computation of fibre curl Fibre curl, rc,is computed a
46、s: f2f2mc2+=Zr (A.5) where Zmis the overhang distance. 9 EN 60793-1-34:2006 Light source Rotating holder Digital filar MicroscopeCCD Camera Fibre sample Analyzer Monitor Vacuum chuck Diffuser Read out IEC 419/06 Figure A.1 Schematic diagram for apparatus to measure fibre curl using an optical micros
47、cope Scanning beam Reference edge Laser micrometer Stepper motor Fibre Magnetic chuck Vacuum chuck Computer IEC 420/06 Figure A.2 Schematic diagram for apparatus to measure fibre curl using a laser micrometer EN 60793-1-34:2006 10 Fibre clamp Motor CCD camera Fibre under test White light source Ferr
48、ule 10 Objectif IEC 421/06 Figure A.3 Schematic diagram for apparatus to measure fibre curl while securing the sample in a ferrule 11 EN 60793-1-34:2006 Annex B (informative) Fibre curl by laser beam scattering B.1 Principle This procedure measures the latent curvature (curl) in an optical fibre by
49、laser beam scattering. This procedure measures the radius of curvature of an uncoated fibre by determining the amount of deflection that occurs as an unsupported fibre end is rotated about the fibres axis. By measuring the differential deflection of two beams separated by a known distance and the geometry of the measuring device, the fibres radius of curvature can be calculated from a simple circular model, the derivation of which is
