SIST EN IEC 62496-2-5:2023

Optical circuit boards - Basic test and measurement procedures - Part 2-5: Flexibility test for flexible opto-electric circuits (IEC 62496-2-5:2022)

This part of IEC 62496-2 defines a test method for folding flexibility inspection of flexible opto-electric circuits with a MIT folding endurance tester and presents a guideline for a step stress test method for finding the predetermined minimum mechanical folding radii below which the flexible opto-electric circuits can be damaged by intended folding distortion. Here, test samples are used instead of products for the flexibility test of their flexible opto-electric circuits, and the test samples have the same layer structure as the products.

Optische Leiterplatten - Grundlegende Prüf- und Messverfahren - Teil 2-5: Biegsamkeitstest für biegsame opto-elektrische Schaltkreise (IEC 62496-2-5:2022)

Cartes à circuits optiques - Procédures fondamentales d’essais et de mesures - Partie 2-5: Essai de flexibilité pour les circuits optoélectriques souples (IEC 62496-2-5:2022)

IEC 62496-2-5:2022 définit une méthode d’essai pour l’examen de la flexibilité au pliage des circuits optoélectriques souples au moyen d’un appareil de contrôle de la flexibilité, et fournit un guide qui présente une méthode d’essai sous contrainte échelonnée destinée à déterminer les rayons de pliage mécanique minimaux prédéterminés en deçà desquels les circuits optoélectriques souples peuvent être endommagés par la distorsion induite par un pliage intentionnel. Des échantillons d’essai sont utilisés ici à la place des produits pour l’essai de flexibilité de leurs circuits optoélectriques souples, et ces échantillons d’essai sont constitués du même matériau, ont la même structure de couches et utilisent la même technologie et les mêmes équipements de traitement que les produits eux-mêmes.

Plošče z optičnimi vezji - Osnovni preskusni in merilni postopki - 2-5. del: Preskušanje upogljivosti za zvijava optoelektrična vezja (IEC 62496-2-5:2022)

Ta del standarda IEC 62496-2 opredeljuje preskusno metodo za preskušanje upogljivosti zvijavih optoelektričnih vezij z napravo za preskušanje vzdržljivosti pregibanja MIT in predstavlja smernice za metodo stopenjskega preskusa obremenitve, da se ugotovi vnaprej določen minimalni mehanski zgibni polmer, pod katerim se zvijava optoelektrična vezja lahko poškodujejo zaradi namernega zvijanja. Tukaj se namesto izdelkov uporabljajo preskusni vzorci za preskušanje prožnosti njihovih zvijavih optoelektričnih vezij. Preskusni vzorci imajo enako strukturo plasti kot izdelki.

General Information

• Status: Published
• Public Enquiry End Date: 28-Feb-2022
• Publication Date: 30-Jan-2023
• ICS: 31.180 - Printed circuits and boards
• ICS: 33.180.01 - Fibre optic systems in general
• Technical Committee: MOC - Mobile Communications
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 23-Jan-2023
• Due Date: 30-Mar-2023
• Completion Date: 31-Jan-2023
• Ref Project: EN IEC 62496-2-5:2023 - Optical circuit boards - Basic test and measurement procedures - Part 2-5: Flexibility test for flexible opto-electric circuits

Overview

EN IEC 62496-2-5:2023 specifies a standardized method to assess the folding flexibility of flexible opto‑electric circuits used on optical circuit boards. The standard defines use of a folding (MIT) endurance tester and gives a guideline for a step stress test to determine the minimum mechanical folding radii at which flexible opto‑electric circuits may be damaged. Tests are performed on representative test samples that share the same materials, layer structure and processing as the finished products.

Key topics and requirements

• Scope and purpose: Provides a repeatable test method for folding flexibility inspection and a step‑stress approach to identify critical bending radii.
• Apparatus: Describes required equipment such as the flexibility/folding endurance tester, folding jigs (examples in the standard include radii from about 1.0 mm to 10.0 mm), laser sources, photo detectors, relay switches and main controllers.
• Test samples: Requires FOECB (flexible opto‑electric circuit board) test samples to have the same layer structure and materials as production parts; separate provisions for optical fibre‑type and planar optical waveguide‑type samples.
• Procedures: Covers preparation, initial optical/electrical measurements, sample mounting, folding/flexibility measurement cycles, final optical/electrical measurements and mechanical performance checks.
• Step stress guideline: Outlines a method to progressively reduce bending radius to find the predetermined minimum radius that causes damage.
• Reporting: Specifies the information to record and report test conditions and results for reproducibility and comparison.

Practical applications and users

• Who uses it: R&D engineers, reliability/test laboratories, quality assurance teams, contract manufacturers and procurement/specification authors working with optical circuit boards and flexible opto‑electric assemblies.
• How it’s used:
  • Validate design robustness of flexible opto‑electric circuits against intended folding or bending in product use.
  • Establish manufacturing acceptance criteria and incoming inspection procedures.
  • Support failure analysis by reproducing folding damage thresholds.
  • Provide objective data for design trade‑offs (flexibility vs optical/electrical performance).
• Benefits: Enables consistent, comparable test results across suppliers and labs and helps define safe bending limits for product integration.

Related standards

• EN/IEC 62496 series (other parts covering optical attenuation, isolation, measurements)
• IEC 60793‑2 (optical fibres)
• IEC 60068‑1 (environmental testing - general)
• ISO 5626 (folding endurance - referenced methodology)

Keywords: EN IEC 62496-2-5:2023, flexibility test, flexible opto-electric circuits, optical circuit boards, folding endurance tester, folding radius, step stress test, FOECB, optical reliability.

Standards Content (Sample)

SLOVENSKI STANDARD
01-marec-2023
Plošče z optičnimi vezji - Osnovni preskusni in merilni postopki - 2-5. del:
Preskušanje upogljivosti za zvijava optoelektrična vezja (IEC 62496-2-5:2022)
Optical circuit boards - Basic test and measurement procedures - Part 2-5: Flexibility test
for flexible opto-electric circuits (IEC 62496-2-5:2022)
Optische Leiterplatten - Grundlegende Prüf- und Messverfahren - Teil 2-5:
Biegsamkeitstest für biegsame opto-elektrische Schaltkreise (IEC 62496-2-5:2022)
Cartes à circuits optiques - Procédures fondamentales d’essais et de mesures - Partie 2-
5: Essai de flexibilité pour les circuits optoélectriques souples (IEC 62496-2-5:2022)
Ta slovenski standard je istoveten z: EN IEC 62496-2-5:2023
ICS:
31.180 Tiskana vezja (TIV) in tiskane Printed circuits and boards
plošče
33.180.01 Sistemi z optičnimi vlakni na Fibre optic systems in
splošno general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 62496-2-5

NORME EUROPÉENNE
EUROPÄISCHE NORM January 2023
ICS 33.180.01
English Version
Optical circuit boards - Basic test and measurement procedures
- Part 2-5: Flexibility test for flexible opto-electric circuits
(IEC 62496-2-5:2022)
Cartes à circuits optiques - Procédures fondamentales Optische Leiterplatten - Grundlegende Prüf- und
d'essais et de mesures - Partie 2-5: Essai de flexibilité pour Messverfahren - Teil 2-5: Biegsamkeitstest für biegsame
les circuits optoélectriques souples opto-elektrische Schaltkreise
(IEC 62496-2-5:2022) (IEC 62496-2-5:2022)
This European Standard was approved by CENELEC on 2023-01-11. 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 bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre 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 CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2023 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 62496-2-5:2023 E

European foreword
The text of document 86/605/FDIS, future edition 1 of IEC 62496-2-5, prepared by IEC/TC 86 "Fibre
optics" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2023-10-11
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2026-01-11
document have to be withdrawn
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 62496-2-5:2022 was approved by CENELEC as a
European Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standard indicated:
IEC 60793-2-10 NOTE Harmonized as EN IEC 60793-2-10
IEC 60793-2-20 NOTE Harmonized as EN 60793-2-20
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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.
NOTE 1 Where an International Publication has been modified by common modifications, indicated by (mod), the
relevant EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60068-1 - Environmental testing - Part 1: General EN 60068-1 -
and guidance
IEC 60793-2 series Optical fibres - Part 2: Product EN IEC 60793-2 series
specifications
IEC 62496-2-1 - Optical circuit boards - Part 2-1: EN 62496-2-1 -
Measurements - Optical attenuation and
isolation
ISO 5626 1993 Paper - determination of folding endurance - -

IEC 62496-2-5 ®
Edition 1.0 2022-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Optical circuit boards – Basic test and measurement procedures –

Part 2-5: Flexibility test for flexible opto-electric circuits

Cartes a circuits optiques – Procédures fondamentales d’essais et de mesures

–
Partie 2-5: Essai de flexibilité pour les circuits optoélectriques souples

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.01 ISBN 978-2-8322-6119-4

– 2 – IEC 62496-2-5:2022 © IEC 2022
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Apparatus . 7
4.1 General description . 7
4.2 Flexibility tester for flexibility test of FOECBs . 8
4.2.1 FOECBs test sample of fibre optical types . 8
4.2.2 FOECBs test sample of planer waveguide optical circuit types . 8
4.3 O-E signal control source . 9
4.4 Laser source . 9
4.5 Photo detector . 9
4.6 Folding jig . 9
4.7 Relay switch . 10
4.8 Main controller . 10
5 Test sample . 10
5.1 FOECB test samples of optical fibre-types . 10
5.2 FOECB test samples of planar optical waveguide-types . 11
6 Procedures . 13
6.1 For test samples of optical fibre-types . 13
6.1.1 Preparing test samples . 13
6.1.2 Initial optical and electrical performance measurement . 13
6.1.3 Setting the test sample . 13
6.1.4 Flexibility measurement . 14
6.1.5 Final optical and electrical performance measurement . 14
6.1.6 Mechanical performance measurement . 14
6.2 For test samples of the planar optical waveguide-types. 14
6.2.1 Preparing test samples . 14
6.2.2 Initial optical and electrical performance measurement . 14
6.2.3 Setting the test sample . 15
6.2.4 Flexibility measurement . 15
6.2.5 Final optical and electrical performance measurement . 15
6.2.6 Mechanical characteristic measurement . 16
7 Report . 16
Annex A (informative) Detail requirement for structure of FOECB test samples of
optical fibre-types . 17
Annex B (informative) Requirement for structure of FOECB test samples of planar
optical waveguide-types . 18
Annex C (informative) Guideline for flexibility folding jig setting conditions of FOECB
test samples . 19
Bibliography . 20

Figure 1 – Schematic diagram of flexible opto-electric circuit board (top view) . 7
Figure 2 – Overview of the folding jig . 8
Figure 3 – Schematic diagram of the flexibility test system for fibre optical circuits . 8

IEC 62496-2-5:2022 © IEC 2022 – 3 –
Figure 4 – Schematic diagram of the flexibility test system for planar waveguide optical
circuits . 9
Figure 5 – Flexibility folding jigs (from the left, folding radius r is 1,0 mm, 2,0 mm, 3,0

mm, 4,0 mm, 5,0 mm and 10,0 mm) . 10
Figure 6 – Schematic diagram of FOECB test samples of optical fibre-types . 11
Figure 7 – Schematic diagram of FOECB test samples of planar optical waveguide-
types. 12
Figure B.1 – Schematic diagram of the flexibility test system for planar waveguide
optical circuits . 18
Figure C.1 – An example of measurement result of optical loss versus bending
diameter . 19

– 4 – IEC 62496-2-5:2022 © IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL CIRCUIT BOARDS –
BASIC TEST AND MEASUREMENT PROCEDURES –

Part 2-5: Flexibility test for flexible opto-electric circuits

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
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consensus of opinion on the relevant subjects since each technical committee has representation from all
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
IEC 62496-2-5 has been prepared by IEC technical committee 86: Fibre optics. It is an
International Standard.
The text of this International Standard is based on the following documents:
Draft Report on voting
86/605/FDIS 86/609/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.

IEC 62496-2-5:2022 © IEC 2022 – 5 –
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
A list of all parts in the IEC 62496 series, published under the general title Optical circuit boards,
can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The "colour inside" logo on the cover page of this document indicates that it
contains colours which are considered to be useful for the correct understanding of its
contents. Users should therefore print this document using a colour printer.

– 6 – IEC 62496-2-5:2022 © IEC 2022
OPTICAL CIRCUIT BOARDS –
BASIC TEST AND MEASUREMENT PROCEDURES –

Part 2-5: Flexibility test for flexible opto-electric circuits

1 Scope
This part of IEC 62496 defines a test method for folding flexibility inspection of flexible opto-
electric circuits with a flexibility tester endurance tester and presents a guideline for a step
stress test method for finding the predetermined minimum mechanical folding radii below which
the flexible opto-electric circuits can be damaged by intended folding distortion. Here, test
samples are used instead of products for the flexibility test of their flexible opto-electric circuits,
and the test samples have the same material, layer structure, processing technology and
equipment as the products.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 60068-1, Environmental testing – Part 1: General and guidance
IEC 60793-2 (all parts), Optical fibres – Part 2: Product specifications
IEC 62496-2-1, Optical circuit boards – Part 2-1: Measurements – Optical attenuation and
isolation
ISO 5626:1993, Paper – Determination of folding endurance
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 62496-1 and the
following apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1
flexible opto-electric circuit board
flexible circuit board that contains both optic and electric circuits integrated into a flexible sheet

IEC 62496-2-5:2022 © IEC 2022 – 7 –

Figure 1 – Schematic diagram of flexible opto-electric circuit board (top view)
Note 1 to entry: Figure 1 shows an example of the top view of a flexible opto-electric circuit board.
Note 2 to entry: There are two types of flexible opto-electric circuit board: optical fibre-types and planer optical
waveguide-types.
[SOURCE: ISO 5626:1993, Clause 1]
3.2
flexibility tester
instrument for folding endurance test of flexible sheets with interchangeable folding heads,
allowing a range of thickness up to 1,25 mm
Note 1 to entry: In general, it is called the MIT folding endurance tester.
4 Apparatus
4.1 General description
The flexibility test system for flexibility test of the flexible opto-electric circuit board (hereafter
FOECB) shall be used for finding of the minimum folding radii of both optic and electric circuits
of the FOECB before any functional damage occurs. An existing flexibility folding method has
been used for testing the folding flexibility of only electric circuits. However, in this document,
it shall be used for testing the folding flexibility of both optic and electric circuits.
Since the test sample for fibre optical type should be connected to the flexibility test system
through an optical fibre, real-time monitoring may be possible. Accordingly, the flexibility tester
shall be configured with a real-time monitoring system using a laser signal device to accurately
know the time of breakage of the optical fibres.
Generally, test samples for planar waveguide optical circuits are difficult to measure through
real-time monitoring because it is not easy to connect to a flexibility test device through an
optical fibre. Therefore, the test sample should be tested by connecting only electric circuits as
in the existing flexibility folding method. The failure time of the test sample should be measured
separately using a visual light on the planar waveguide circuits.
But, in case of that the test sample for planar waveguide optical circuits shall use optical fibres
with connector to coupling with the optical waveguide, flexibility test of the test samples can be
possible with real-time monitoring.
In addition, these tests should be measured in the process of replacing the holding jig.The test
sample shall be clamped by the folding jig within the main controller as shown in Figure 2.

– 8 – IEC 62496-2-5:2022 © IEC 2022

a) Photograph diagram of the folding jig b) Photograph of a folding jig and test sample

Figure 2 – Overview of the folding jig
4.2 Flexibility tester for flexibility test of FOECBs
4.2.1 FOECBs test sample of fibre optical types
The flexibility test system for fibre optical circuits should be configured to stop the folding action
of the test sample if any damage starts to appear in its optical and electrical sections. Therefore,
the flexibility test system shall be composed of an optic-electric signal control source (hereafter
referred as O-E signal control source), test sample, and main controller, as shown in Figure 3.

Figure 3 – Schematic diagram of the flexibility test system for fibre optical circuits
4.2.2 FOECBs test sample of planer waveguide optical circuit types
The flexibility test system for planer waveguide optical circuits shall be constructed in the same
form as the folding flexibility test method for existing electrical circuits, as shown in Figure 4.

IEC 62496-2-5:2022 © IEC 2022 – 9 –

Figure 4 – Schematic diagram of the flexibility test system
for planar waveguide optical circuits
4.3 O-E signal control source
An O-E signal control source shall be composed of a laser source, photo detector, relay switch,
electric power source, optical fibre, and optical connectors. The O-E signal control source
supplies an optical signal to the test sample, and allows the photo detector to control the relay
switch based on detected optical signal for on-off switching of the electric signal flow (current)
within the flexibility test system.
4.4 Laser source
The optical output power of the laser source shall have enough larger of the minimum detected
power of optical detector and attenuation (optical loss) of samples. The laser source in the O-
E signal control source sends an optical signal to the test sample via its optical input terminal
connected to the protruded optical fibre. The wavelength and mode of the laser source should
be chosen according to the application to be used. The launching mode of the laser source
should be appropriate to the application of the relevant specification of O-E circuit board.
4.5 Photo detector
The minimum detected optical power of the photo detector shall be enough to detect the optical
power after attenuating the optical power by the test sample and light source power. The photo
detector detects the optic signal flow in the test sample. The photo detector output controls the
relay switch inside the O-E signal control source. Therefore, the output current of the photo
detector shou
...