1、BRITISH STANDARD Fibre optic interconnecting devices and passive components - Basic test aiLd measurement procedures - Part 3-23: Examination and measurements - Fibre position relative to ferrule endface The European Standard EN 613003231998 has the status of a British Standard ICC 33.180.20 BS EN 6
2、1300-3-23:1998 IEC 61300-3-23:1998 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW sG- STD-BSI BS EN bL300-3-23-ENGL 1778 118 1b24bb7 0729391 187 BS EN 613003-23:1998 This British Standard, having been prepared under the direction of the Electrotechnicai Sector Board, was publ
3、ished under the authority of the Standards Board and comes into effect on 15 October 1998 National foreword This British Standard is the English language version of EN 6130W231998. It is identical with IEC 61300523: 1998. The UK participation in its preparation was entrusted by Technical Committee G
4、EM6, Fibre optics, to Subcommittee GEU862, interconnecting devices and passive components, which has the responsibility to: - aid enquirers to understand the text; - present to the responsible internationalEuropean committee any enquiries on the interpretation, or proposals for change, and keep the
5、UK interests informed; - monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this subcommittee can be obtained on request to its secretary. From 1 January 1997, all IEC publications have the number 60000 added to the old numbe
6、r. For instance, IEC 27-1 has been renumbered as IEC 60027-1. For a period of time during the change over from one numbering system to the other, publications may contain identifiers from both systems. Cross-references Attention is drawn to the fact that CEN and CENELEC Standards normaiiy include an
7、 annex which lists normative references to international publications with their corresponding European publications. The British Standards which implement these international or European publications may be found in the BSI Standards Catalogue under the section entitled “International Standards Cor
8、respondence Index”, or by using the “Find facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standarch are responsible for their correct application. Compliance with a British Standard does n
9、ot of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 18, an inside back cover and a back cover. Amendments issued since publication Amd.No- ID b) method 2: analyzing the endface with a three-
10、dimensional interferometry type surface analyzer; c) method 3: analyzing the endface with a two-dimensional interferometry type surface an a I yze r . Method 1 is the reference method. 2 Apparatus 2.1 The apparatus shown in figure 2 consists of a suitable ferrule holder, a positioning stage and a tw
11、o-dimensional surface analyzer. Method 1 - Two-dimensional 8urface analysis 2.1.1 Ferrule holder The ferrule holder is a suitable device to hold the ferrule in a fixed vertical position, or in a tilted position in the case of an angled ferrule type, 2.1.2 Positioning stage The ferrule holder is fixe
12、d to the positioning stage, which shall enable the holder to be moved to the appropriate position. The stage shall have enough rigidity so as to measure the ferrule endface with a precision of some nanometres. TmI-dimensional surface analyzer Profilometer , Ferrule endface Probe I Positioning stage
13、Ferrule s IEC 50*/98 Figure 2 - Apparatus for two-dimensional surface analysis _ STD-BSI BS EN b1300-3-23-ENGL 1978 D Lb24bb7 0727397 bT5 D Page 6 EN 61300-3-23:1998 2.1.3 Two-dimensional surface analyzer The two-dimensional surface analyzer shall have an ability to measure the profile of the ferrul
14、e endface with an accuracy better than f10 nm. The analyzer shall consist of a profilometer, a profile data processing unit and a monitor. The profilometer shall be equipped with a wedge type probe arranged so that the motion of the trace is perpendicular to the ferrule axis. The profile data proces
15、sing unit shall be able to process the profile data so as to measure the fibre undercut or protrusion: the unit calculates an ideal circle fitted to the spherical ferrule endface from the measured profile data and calculates converted data from the measured profile data by extracting the ideal circl
16、e data. The monitor shall display the measured and calculated profiles. 2.2 The apparatus shown in figure 3 consists of a suitable ferrule holder, a positioning stage and a three-dimensional interferometry analyzer. Method 2 - Three-dimensional surface analysis by interferometry system 2.2.1 Ferrule
17、 holder The ferrule holder is a suitable device to hold the ferrule in a fixed vertical position, or in a tilted position in the case of an angled ferrule type. 2.2.2 Positioning stage The ferrule holder is fixed to the positioning stage, which shall enable the holder to be moved to the appropriate
18、position. The stage shall have enough rigidity so as to measure the ferrule endface with a precision of some nanometres. 2.2.3 Three-dimensional interferometry analyzer The three-dimensional interferometry analyzer shall have an ability to measure the surface of the ferrule endface with an accuracy
19、better than f10 nm. The analyzer shall consist of a microscope unit, a surface data processing unit, and a monitor. The microscope unit shall consist of an interference microscope, an actuator, and an image scanner. The interference microscope equipped with an objective is arranged so that its motio
20、n is parallel to the axis of the ferrule. The actuator transports the objective vertically. The image scanner converts interference image signals into position data. The surface data processing unit shall be able to process the position data so as to measure the fibre undercut or protrusion: the uni
21、t calculates an ideal spherical surface fitted to the spherical ferrule endface from the measured surface data and calculates converted surface data from the measured surface data by extracting the ideal spherical surface data. The unit also has an ability to correct the surface data taking into acc
22、ount the difference in refractive indices and absorption coefficients of the fibre and the ferrule. The monitor shall display the measured and calculated three-dimensional surface profiles. STD-BSI BS EN b1300-3-23-ENGL 1998 m 1b2Libb9 0729398 531 m Page 7 EN 61300-3-23:1998 Three-dimensional interf
23、erometry analyzer Microscope unit interference microscope I surface data processing unit Actuator objective 1 I I / , Ferrule endface Femile /c 5LzyBB Positioning stage Figure 3 - Apparatus for three-dimensional surface analysis by interferometry Bystem 2.3 The apparatus shown in figure 4 consists o
24、f a suitable ferrule holder, a positioning stage, and a two-dimensional interferometry analyzer. Method 3 - Two-dimensional surface rrnalysis by interferometry system 2.3.1 Ferrule holder The ferrule holder is a suitable device to hold the ferrule in a fixed vertical position, or in a tilted positio
25、n in the case of an angled ferrule type. 2.3.2 Positioning stage The ferrule holder is fixed to the positioning stage, which shall enable the holder to be moved to the appropriate position. The stage shall have enough rigidity so as to measure the ferrule endface with a precision of some nanometres.
26、 Page 8 EN 61300-3-23:1998 2.3.3 Two-dimensional interferometry analyzer The two-dimensional interferometry analyzer shall have the ability to measure the profile of the ferrule endface with an accuracy better than I10 nm. The analyzer shall consist of a micro- scope unit with a monochromatic light
27、source, an image data processing unit, and a monitor. The microscope unit shall consist of an interference microscope equipped with a video camera to send the interference image of the ferrule surface to the video board of the image data processing unit. The image data processing unit shall be able
28、to process a row (or a group of close rows to cover a narrow stripe) of the video image passing across a fibre diameter: the unit calculates the characteristic parameters (frequency and phase) of the interference light intensity curve of the analyzed row by fitting the acquired data with a theoretic
29、al function. The undercut or protrusion are evaluated from the phase shift of the interference fringes in the fibre zone in respect to the ones in the ferrule zones. The system must be able to recognize the 27t phase shifts. The unit also has an ability to correct the surface data taking into accoun
30、t the differences in refractive indices and absorption coefficients of the fibre and the ferrule. The monitor shall display the light intensity curve, the fitting functions and the measurement results. Ferule Two-dimensional interferometry analyzer Microscope unit Interference microscope - I image d
31、ata processing unit with video board I Positioning stage IEC Figure 4 - Apparatus for two-dimensional surface analysis by interferometry system STD-BSI BS EN b2300-3-23-ENGL 1998 Lb24bb9 0729400 TIT .S Page 9 EN 61300-3-23:1998 3 Procedure 3.1 Measurement ragions Three regions shall be defined on th
32、e ferrule endface for the measurement (see figure 5): a) fitting region: the fitting region is set on the ferrule surface and defined by a circular region having a diameter D minus the diameter E of the extracting region. The fitting region shall be defined in order to cover the contact zone of the
33、ferrule endface when the ferrule is mated; b) extracting region: the extracting region, which includes the fibre endface region and the adhesive region, is defined by a circle having a diameter E; c) averaging region: the averaging region is set on the fibre surface, and defined by a circle having a
34、 diameter F. The three regions shall be centred on the ferrule axis. For connectors with a 125 pm nominal fibre diameter and a curvature radius of the spherically polished ferrule endface of about 8 mm to 25 mm, the values of the diameters D, E and Fare as follows: D = 250 pm; E= 140 pm; F= 50 pm. F
35、errule endface I Fekle Fibre Adhesive IEC 507m Figure 5 - Ferrule endface and measurement regions Page 10 EN 61300-3-231998 3.2 Method 1 - Two-dimensional surface analysis NOTE - The traces of some profilometers only show the surface finish and may not accurately show the curvature of the surface. 3
36、.2.1 Affix the ferrule in the ferrule holder so that the portion of the ferrule closest to the endface is held with the holder. The length of the ferrule contacting the holder shall be twice the diameter of the ferrule. 3.2.2 Adjust the chisel tip of the profilometer so that the bottom edge of the t
37、ip is perpendicular to the axis of the ferrule. 3.2.3 ferrule. Adjust the ferrule holder so that the profilometer trace passes through the axis of the 3.2.4 data on the profile data processing unit. Cause the profilometer to trace across the surface of the endface, recording the profile 3.2.5 Take t
38、he profile data of the fitting region from the measured profile data, and calculate an ideal circle so as to fit the fitting region; then evaluate w. A recommended evaluation procedure is given in annex A. In general, the procedure may be as follows: a) create a converted profile from the measured p
39、rofile data by extracting the ideal circle data and display it on the monitor. The fitting region of the converted prafile may be straight and coincide with the line for the ideal circle when the ferrule endface has an ideal spherical surface (see figure 6); b) when the ferrule endface does not have
40、 an ideal spherical surface, the fitting region of the converted profile may not coincide with the line for the ideal circle (see figure 7). In this case, alter the diameter of the ideal circle and continue the procedure of item a) so that the converted profile has the smallest peak-to-valley (PV) v
41、alue; c) calculate an average height of the averaging region on the fibre and an average height of the fitting region on the ferrule from the converted profile (see figure 6). The fibre undercut +w or protrusion -ware measured as the difference between the two average heights. For reference, the con
42、verted profile used for the evaluation of w and the relevant radius shall be given. STD-BSI BS EN bL300-3-23-ENGL 1778 lb24bb7 0729402 72 Page 11 EN 61300-3-23:1998 Extracng region Fibre undercut +w Fibre protrusion -w Fibre protrusion -w IK: 5o calculate an average height on the averaging fibre reg
43、ion and an average height on the fitting ferrule portion from the converted surface. The fibre undercut +w or protrusion -w are measured as the difference between the two average heights, as shown in figure 11; for reference, the converted surface used for the evaluation of w and the relevant radius
44、 shall be given. 70); Page 13 EN 61300-3-23:1998 IEC 51W Figure 8 - Ferrule endface murface Averaging regio Extracting region IEC 511198 Figure B - Fitting region and averaging region of the ferrule endface surface IEC 51H Figure 10 - Converted endface surface of the global ferrule (see figure 8) Pa
45、ge 14 EN 61300-3-23:1998 Averaging region Extracting region Fibre undercut +w fibre protrusion -w or IEC 51m Figure 11 - Converted ferrule endface surface subtracting the extracting region (see figure 9) 3.4 Method 3 - Two-dimensional surface analysis by interferometry system NOTE - The difference i
46、n refractive indices and the absorption coefficients between the ferrule and the fibre should be taken into account when processing the measured surface data. If the procedure is done without consideration of the difference, the procedure described in this section may not accurately show the fibre u
47、ndercut or protrusion. 3.4.1 Affix the ferrule in the holder so that the portion of the ferrule closest to the endface is held with the holder. The length of the ferrule contacting the holder shall be twice the diameter of the ferrule. 3.4.2 Adjust the holder position so that the image of the ferrul
48、e endface in the fibre zone is under the microscope objective and send the image to the monitor. 3.4.3 Adjust the interferometry device so that the interference fringes appear on the endface ferrule surface. 3.4.4 Adjust the interferometry device so that the interference fringes are perpendicular to
49、 the fibre diameter that shall be analyzed. 3.4.5 Select the row that will be analyzed and cause the system to acquire the image, recording the light intensity of the selected row (see figure 12: image). 3.4.6 Take the part of the intensity curve corresponding to the fitting region of the profile and calculate the theoretical function to fit it (see figure 12: diagram). STD-BSI BS EN bL300-3-23-ENGL 1998 I Lb24bh9 0729406 438 I Page 16 EN 61300-3-231998 The theoretical fitting function for Michelson interferometry is: P(X) = A + B COS(FM (x
