oSIST prEN IEC 61978-1:2023
(Main)Fibre optic interconnecting devices and passive components - Fibre optic passive chromatic dispersion compensators - Part 1: Generic specification
Fibre optic interconnecting devices and passive components - Fibre optic passive chromatic dispersion compensators - Part 1: Generic specification
D133/C027: DOW = DOR + 12 months
Lichtwellenleiter - Verbindungselemente und passive Bauteile - Passive Lichtwellenleiter - Kompensatoren mit chromatischer Dispersion - Teil 1: Fachgrundspezifikation
Dispositifs d'interconnexion et composants passifs à fibres optiques - Compensateurs de dispersion chromatique passifs à fibres optiques - Partie 1: Spécification générique
Optični spojni elementi in pasivne komponente - Optični pasivni kompenzatorji barvne razpršenosti - 1. del: Splošna specifikacija
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
oSIST prEN IEC 61978-1:2023
01-julij-2023
Optični spojni elementi in pasivne komponente - Optični pasivni kompenzatorji
barvne razpršenosti - 1. del: Splošna specifikacija
Fibre optic interconnecting devices and passive components - Fibre optic passive
chromatic dispersion compensators - Part 1: Generic specification
Lichtwellenleiter - Verbindungselemente und passive Bauteile - Passive Lichtwellenleiter
- Kompensatoren mit chromatischer Dispersion - Teil 1: Fachgrundspezifikation
Dispositifs d'interconnexion et composants passifs à fibres optiques - Compensateurs de
dispersion chromatique passifs à fibres optiques - Partie 1: Spécification générique
Ta slovenski standard je istoveten z: prEN IEC 61978-1:2023
ICS:
33.180.20 Povezovalne naprave za Fibre optic interconnecting
optična vlakna devices
oSIST prEN IEC 61978-1:2023 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN IEC 61978-1:2023
86B/4753/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 61978-1 ED4
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2023-05-26 2023-08-18
SUPERSEDES DOCUMENTS:
86B/4698/CD, 86B/4738A/CC
IEC SC 86B : FIBRE OPTIC INTERCONNECTING DEVICES AND PASSIVE COMPONENTS
SECRETARIAT: SECRETARY:
Japan Mr Shigeru Tomita
OF INTEREST TO THE FOLLOWING COMMITTEES: PROPOSED HORIZONTAL STANDARD:
Other TC/SCs are requested to indicate their interest, if
any, in this CDV to the secretary.
FUNCTIONS CONCERNED:
EMC ENVIRONMENT QUALITY ASSURANCE SAFETY
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Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft
for Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
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This document is still under study and subject to change. It should not be used for reference purposes.
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the final stage for submitting ISC clauses. (SEE AC/22/2007 OR NEW GUIDANCE DOC).
TITLE:
Fibre optic interconnecting devices and passive components - Fibre optic passive chromatic
dispersion compensators - Part 1: Generic specification
PROPOSED STABILITY DATE: 2033
NOTE FROM TC/SC OFFICERS:
Copyright © 2023 International Electrotechnical Commission, IEC. All rights reserved. It is permitted to download
this electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee
positions. You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other
purpose without permission in writing from IEC.
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IEC CDV 61978-1/Ed4 © IEC 2023 – 2 – 86B/4753/CD
1 CONTENTS
2
3 CONTENTS . 2
4 FOREWORD . 4
5 1. Scope . 6
6 2. Normative references . 6
7 3. Terms and definitions . 7
8 3.1 Component terms . 7
9 3.2 Performance terms . 8
10 4 Requirements . 10
11 4.1 Classification . 10
12 4.1.1 General . 10
13 4.1.2 Technology . 11
14 4.1.3 Wavelength band . 11
15 4.1.4 Application of PDCSs and their suitable technologies . 11
16 4.1.5 Interface style . 11
17 4.2 Documentation . 12
18 4.2.1 Symbols . 12
19 4.2.2 Drawings . 12
20 4.2.3 Tests and measurements . 12
21 4.2.4 Test report . 12
22 4.2.5 Instructions for use . 13
23 4.3 Standardisation system . 13
24 4.3.1 Interface standards . 13
25 4.3.2 Performance standards . 13
26 4.3.3 Reliability standards . 13
27 4.4 Design and construction. 13
28 4.4.1 Materials . 13
29 4.4.2 Workmanship . 13
30 4.5 Quality . 13
31 4.6 Performance requirements . 13
32 4.7 Identification and marking . 14
33 4.7.1 General . 14
34 4.7.2 Component marking . 14
35 4.7.3 Package marking . 14
36 4.8 Packaging . 14
37 4.9 Storage conditions . 14
38 4.10 Safety . 14
39 Annex A (informative) Example of dispersion compensating fibre (DCF) technologies . 16
40 Annex B (informative) Example of fibre Bragg grating (FBG) technologies . 18
41 Annex C (informative) Example of virtually imaged phased array (VIPA) technologies . 20
42 Annex D (informative) Example of GT etalon technologies . 22
43 Annex E (informative) Technology dependent characteristics of PCDCs . 23
44 Annex F (informative) Example of interface style . 24
45
46 Figure A.1 – Chromatic dispersion in a standard single-mode optical fibre (SMF) . 16
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47 Figure A.2 – Calculated contour for different dispersion at the wavelength of 1,55 µm
48 (CD(λ:1,55 µm)) for a step index core fibre . 17
49 Figure A.3 – Examples of refractive index profile used in DCF . 17
50 Figure B.1 – Illustration of the use of a chirped fibre Bragg grating for chromatic
51 dispersion compensation . 18
52 Figure B.2 – Expanded view over 10 nm of the insertion loss spectrum of a multi-
53 channel FBG . 19
54 Figure C.1 – Structure of virtually imaged phased array (VIPA) . 20
55 Figure C.2 – Detailed light path and mechanism of generating chromatic dispersion . 21
56 Figure D.1 – Gires-Tournois etalon . 22
57 a) Configuration A – Device integral fibre pigtails without a connector . 24
58 b) Configuration B – Device containing integral fibre optic pigrails with a connector
59 plug on each port. . 24
60 c) Configuration C – Device containing connector receptacles as an integral port of the
61 device housing . 24
62 d) Congfiguration D – Example – Device containing some combination of the
63 interfacing feature of the preceding configurations . 24
64
65 Table 1 – Example of a typical fibre optic PDCS classification . 11
66 Table 2 – Application, channel numbers, passband and technologies of PDCSs . 11
67 Table E.1 – Summary of technology dependent characteristics of PCDCs . 23
68
69
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70 INTERNATIONAL ELECTROTECHNICAL COMMISSION
71 ____________
72
73 FIBRE OPTIC INTERCONNECTING DEVICES
74 AND PASSIVE COMPONENTS – FIBRE OPTIC PASSIVE
75 CHROMATIC DISPERSION COMPENSATORS –
76
77 Part 1: Generic specification
78
79 FOREWORD
80 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
81 all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
82 co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
83 in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
84 Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
85 preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
86 may participate in this preparatory work. International, governmental and non-governmental organizations liaising
87 with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
88 Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
89 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
90 consensus of opinion on the relevant subjects since each technical committee has representation from all
91 interested IEC National Committees.
92 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
93 Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
94 Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
95 misinterpretation by any end user.
96 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
97 transparently to the maximum extent possible in their national and regional publications. Any divergence between
98 any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
99 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
100 assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
101 services carried out by independent certification bodies.
102 6) All users should ensure that they have the latest edition of this publication.
103 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
104 members of its technical committees and IEC National Committees for any personal injury, property damage or
105 other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
106 expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications.
107 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
108 indispensable for the correct application of this publication.
109 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
110 rights. IEC shall not be held responsible for identifying any or all such patent rights.
111 International Standard IEC 61978-1 has been prepared by subcommittee 86B: Fibre optic
112 interconnecting devices and passive components, of IEC technical committee 86: Fibre optics.
113 This foutrh edition cancels and replaces the third edition, published in 2014, and constitutes a
114 technical revision.
115 This edition includes the following significant technical changes with respect to the previous
116 edition:
117 a) harmonization of terms and definitions with IEC TS 62627-09;
118 b) change of Clause 4 regarding requirements.
119 The text of this standard is based on the following documents:
CDV Report on voting
86B/xxxx/FDIS 86B/xxxx/RVD
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120
121 Full information on the voting for the approval of this standard can be found in the report on
122 voting indicated in the above table.
123 The French version of this standard has not been voted upon.
124 This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
125 A list of all parts in the IEC 61978 series, published under the general title Fibre optic
126 interconnecting devices and passive components – Fibre optic passive chromatic dispersion
127 compensators, can be found on the IEC website.
128 The committee has decided that the contents of this publication will remain unchanged until the
129 stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data related to
130 the specific publication. At this date, the publication will be
131 • reconfirmed,
132 • withdrawn,
133 • replaced by a revised edition, or
134 • amended.
135
IMPORTANT – The “colour inside” logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.
136
137
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138 FIBRE OPTIC INTERCONNECTING DEVICES
139 AND PASSIVE COMPONENTS – FIBRE OPTIC PASSIVE
140 CHROMATIC DISPERSION COMPENSATORS –
141
142 Part 1: Generic specification
143
144 1. Scope
145 This part of IEC 61978 applies to fibre optic passive chromatic dispersion compensators, all
146 exhibiting the following features:
147 – they are optically passive;
148 – they have an optical input and an optical output for transmitting optical power;
149 – the ports are optical fibres or optical fibre connectors;
150 – they are wavelength sensitive;
151 – they may be polarization sensitive.
152 This document establishes uniform requirements for the passive chromatic dispersion
153 compensator.
154 2. Normative references
155 The following documents, in whole or in part, are normatively referenced in this document and
156 are indispensable for its application. For dated references, only the edition cited applies. For
157 undated references, the latest edition of the referenced document (including any amendments)
158 applies.
159 IEC 60027 (all parts), Letter symbols to be used in electrical technology
160 IEC 60050-731, International Electrotechnical Vocabulary – Chapter 731: Optical fibre
161 communication
162 IEC 60617 (all parts), Graphical symbols for diagrams
163 IEC 60695-11-5, Fire hazard testing – Part 11-5: Test flames – Needle-flame test method –
164 Apparatus, confirmatory test arrangement and guidance
165 IEC 60793-2-50, Optical fibres – Part 2-50: Product specifications – Sectional specification for
166 class B single-mode fibres
167 IEC 61300 (all parts), Fibre optic interconnecting devices and passive components – Basic test
168 and measurement procedures
169 IEC 61300-3-38, Fibre optic interconnecting devices and passive components – Basic test and
170 measurement procedures – Part 3-38: Examinations and measurements – Group delay,
171 chromatic dispersion and phase ripple
172 IEC TR 61930, Fibre optic graphical symbology
173 IEC TS 62627-09, Fibre optic interconnecting devices and passive components - Vocabulary
174 for passive optical devices
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175 ISO 129-1, Technical drawings – Indication of dimensions and tolerances – Part 1: General
176 principles
177 ISO 286-1, Geometrical product specifications (GPS) – ISO coding system for tolerances of
178 linear sizes – Part 1: Bases of tolerances and fits
179 ISO 1101, Geometrical Product Specifications (GPS) – Geometrical tolerancing – Tolerances
180 of form, orientation, location and run-out
181 ISO 8601-1, Date and time — Representations for information interchange — Part 1: Basic rules
182 3. Terms and definitions
183 For the purposes of this document, the terms and definitions given in IEC 60050-731 and IEC
184 TS 62627-09, as well as the following definitions apply.
185 3.1 Component terms
186 3.1.1
187 passive chromatic dispersion compensator
188 PCDC
189 two-port in-line passive device used to perform chromatic dispersion compensation
190 Note 1 to entry: PCDCs are commonly used to compensate the chromatic dispersion of an optical path by adding
191 the opposite sign chromatic dispersion.
192 Note 2 to entry: The typical optical paths comprise single-mode fibre, dispersion shifted fibre and/or non-zero
193 dispersion shifted fibre. PCDCs have either negative or positive chromatic dispersion values depending on the
194 chromatic dispersion sign of the optical path.
195 [SOURCE: IEC TS 62627-09:2016, 3.2,17].
196 3.1.2
197 dispersion compensating fibre
198 DCF
199 speciality fibre to compensate for the chromatic dispersion of an optical path
200 3.1.3
201 passive DCF based dispersion compensator
202 PCDC which constitutes DCF; realised by having chromatic dispersion characteristics of
203 opposite sign to that of the optical path which are controlled the refractive index profile of the
204 fibre
205 3.1.4
206 fibre Bragg grating
207 FBG
208 fibre type optical device which has pediodically modulated refractive index profile in the core
209 3.1.5
210 passive FBG based dispersion compensator
211 PCDC which constitutes a FBG; PCDC is realised by a chirped FBG which has gradual change
212 in modulation period and/or refractive index along the fibre axis
213 3.1.6
214 virtually imaged phased array
215 VIPA
216 optical device having a glass plate with a highly reflective mirror
217 Note 1 to entry: A VIPA has the same functions as a grating.
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218 3.1.7
219 passive VIPA based dispersion compensator
220 PCDC which consisting of a VIPA, focusing lens and 3-dimensional mirror
221 Note 1 to entry: PCDC produces both positive and negative chromatic dispersion by the movement of the 3-
222 dimensional mirror to compensate for the chromatic dispersion of an optical path.
223 3.1.8
224 etalon
225 optical cavity which consists of a pair of parallel reflective mirrors
226 3.1.9
227 Gires-Tournois etalon
228 GT etalon
229 etalon having a highly reflective mirror and a half mirror
230 Note 1 to entry: The GT etalon is sometimes called a GT interferometer.
231 3.1.10
232 passive GT etalon based dispersion compensator
233 PCDC which comprises a GT etalon
234 3.2 Performance terms
235 3.2.1
236 chromatic dispersion compensation
237 process by which a specific amount of chromatic dispersion is removed in order to mitigate the
238 system impairment caused by unwanted dispersion
239 3.2.2
240 group delay
241 time by which a pulse is delayed by an optical device
242 Note 1 to entry: The group delay generally varies with the operating wavelength.
243 3.2.3
244 chromatic dispersion
245 derivative of group delay with respect to wavelength or frequency
246 Note 1 to entry: A typical unit is ps/nm or ps/GHz. The chromatic dispersion generally varies with the operating
247 wavelength.
248 Note 2 to entry: The units of ps/GHz are not commonly used; however, it is suitable for the evaluation of
249 transmission system influence.
250 3.2.4
251 dispersion slope
252 derivative of chromatic dispersion with respect to wavelength or frequency
253 Note 1 to entry: A typical unit is ps/nm2 or ps/GHz2.The unit of ps/GHz2 is not commonly used; however, it is
254 suitable for the evaluation of transmission system influence.
255 Note 2 to entry: The dispersion slope generally varies with the operating wavelength
256 3.2.5
257 operating wavelength
258 nominal wavelength λ at which a passive device operates with the specified performance
259 Note 1 to entry: Operating wavelength includes the wavelength to be nominally transmitted, attenuated and isolated.
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260 3.2.6
261 operating wavelength range
262 specified range of wavelengths including all operating wavelengths
263 Note 1 to entry: Operating wavelength range shall include all passbands when two or more the passbands are exist.
264 3.2.7
265 figure of merit
266 FoM
267 ratio of the dispersion to the insertion loss of a PCDC at a particular operating wavelength
268 3.2.8
269 passband
270 wavelength range within which a passive optical device is required to operate with optical
271 attenuation less than or equal to a specified optical attenuation value
272 Note 1 to entry: There may be one or more passbands for a PCDC.
273 3.2.9
274 passband ripple
275 maximum peak-to-peak variation of insertion loss in the passband
276 Note 1 to entry: The passband ripple of a PCDC is defined as the maximum passband ripple for all passbands.
277 3.2.10
278 group delay ripple
279 GDR
280 maximum peak-to-peak variation of the group delay approximated by a desired function of
281 wavelength (or frequency), typically a linear fit, within a channel wavelength (or frequency)
282 range
283 3.2.11
284 phase ripple
285 maximum peak-to-peak variation in measured phase spectrum when compared to a quadratic
286 fit within a channel wavelength (or frequency) range
287 Note 1 to entry: Phase ripple (unit: radian) is calculated as the product of a peak-to-peak group delay ripple (unit: s)
288 and a period of group delay ripple (unit: Hz). Refer to IEC 61300-3-38.
289 3.2.12
290 insertion loss
291 reduction in optical power between an input and output port of a passive device
292 Note 1 to entry: expressed in decibels (dB).
293 Note 2 to entry: insertion loss is expressed as follows:
P
a
294 a=−10log
P
0
295 where
296 P is the optical power launched into the input port;
0
297 P is the optical power received from the output port.
a
298 3.2.13
299 return loss
300 fraction of input power that is returned from a port of a passive device expressed in decibels
301 Note 1 to entry: The return loss is defined as follows:
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P
r
RL=−10log
P
0
302
303 where
304 P is the optical power launched into a port;
0
305 P is the optical power received back from the same port.
r
306
307 reflectance
308 ratio of the optical power returning back from a port to input power expressed in %
309 3.2.14
310 polarization dependent loss
311 PDL
312 maximum variation of insertion loss due to a variation of the state of polarization (SOP) over all
313 the SOPs
314 3.2.15
315 wavelength dependent loss
316 WDL
317 maximum variation of the insertion loss over operating wavelength range
318 3.2.16
319 polarization mode dispersion
320 PMD
321 average delay of the travelling time between the two principal states of polarization (PSP), when
322 an optical signal passes through an passive optical device
323 4 Requirements
324 4.1 Classification
325 4.1.1 General
326 Fibre optic passive chromatic dispersion compensators (PCDCs) are classified either totally or
327 in part in the following categories:
328 - Technology;
329 - Type;
330 - wavelength band;
331 - categories of transmission fibre;
332 - interface style.
333 As example of a typical fibre optic PDCS classification is given in Table 1.
334
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335 Table 1 – Example of a typical fibre optic PDCS classification
Items Classification
Technology DCF
Type Wavelength dispertion compensating
Wavelength band C-band
Category of transmission fibre B-652
Interface style Configuration D
Fibre category: IEC 60793-2-50, B-652
IEC 61754-4 (SC connector)
336 4.1.2 Technology
337 PCDCs typically use the following technologies:
338 – Dispersion compensating fibre (DCF);
339 – Fibre Bragg grating (FBG);
340 – Virtual Image Phased Array (VIPA);
341 – GT etalon.
342 4.1.3 Wavelength band
343 – O-band;
344 – S-band;
345 – C-band;
346 – L-band;
347 – C-band and L-band;
348 – Other wavelength band or combination of wavelength bands above.
349 4.1.4 Application of PDCSs and their suitable technologies
350 The application of PCDCs and the suitable technologies are summarized in Table 2.
351 Table 2 – Application, channel numbers, passband and technologies of PDCSs
Applications Channel number Passbands Technologies
TDM (Time division Single channel Narrow Dispersion compensating
multiplexing) fibre (DCF)
Fibre Bragg grating (FBG)
GT etalon
WDM (Wavelength Single channel Narrow FBG
division multiplexing)
a
Narrow FBG
Multi-channel
GT etalon
Virtually imaged phased
array (VIPA)
Wide DCF
a
Multi-channel PCDCs can be used for a single channel use.
352
353 4.1.5 Interface style
354 PCDC style shall be defined on the basis of the following elements:
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355 - The input and output port configuration;
356 - The connector set type(s), if any.
357 NOTE Examples of interface style are provided in Annex F.
358 4.2 Documentation
359 4.2.1 Symbols
360 Graphical and letter symbols shall, whenever possible, be taken from IEC 60027 series,
361 IEC 60617 and IEC TR 61930.
362 4.2.2 Drawings
363 4.2.2.1 General
364 The drawings and dimensions given in the relevant specifications shall not restrict detail
365 construction nor be used as manufacturing drawings.
366 4.2.2.2 Projection system
367 Either first angle or third angle projection shall be used for the drawings in documents covered
368 by this document. All drawings within a document shall use the same projection system and the
369 drawings shall state which system is used.
370 4.2.2.3 Dimensional system
371 All dimensions shall
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