IEC 60747-5-4:2022

Semiconductor devices - Part 5-4: Optoelectronic devices - Semiconductor lasers

IEC 60747-5-4:2022 specifies the terminology, the essential ratings and characteristics as well as the measuring methods of semiconductor lasers.
This edition includes the following significant technical changes with respect to the previous edition:
- References for the terms and definitions related to the lighting area, IEC 60050-845, are revised based on IEC 60050-845:2020;
- Emission angle is changed to radiation angle in 3.3.2;
- Definitions of rise time and fall time in 3.4.1 are revised based on the publication IEC 60050-521:2002;
- Spectral linewidth is added to Table 1 in Clause 4;
- Conditions for carrier-to-noise ratio of Table 1 in Clause 4 is amended.
- Error in the equation for carrier-to-noise ratio in 5.2.2 is corrected;
- Precaution against the equipment used for carrier-to-noise ratio measurement is added in 5.2.2;
- Explanation for the measurement method of the small signal cut-off frequency in 5.3.2 of the first edition is deleted because it has been defined in the latest version of ISO 11554;
- Reference document for the lifetime in 5.4 is amended;
- Precaution against the measuring arrangement used for the half-intensity width and 1/e2-intensity is added in 5.5.3;
- Reference tables in Annex A, Annex B and Annex C are revised by following the latest version of ISO publications.

General Information

• Status: Published
• Publication Date: 12-Dec-2024
• ICS: 31.080.01 - Semiconductor devices in general
• ICS: 31.260 - Optoelectronics. Laser equipment
• Technical Committee: SC 47E - Discrete semiconductor devices
• Drafting Committee: WG 9 - TC 47/SC 47E/WG 9
• Current Stage: PPUB - Publication issued
• Start Date: 27-Apr-2022
• Completion Date: 20-May-2022

Relations

• Amended By: IEC 60747-5-4:2022/AMD1:2024 - Amendment 1 - Semiconductor devices - Part 5-4: Optoelectronic devices - Semiconductor lasers
• Effective Date: 05-Sep-2023
• Revises: IEC 60747-5-4:2006 - Semiconductor devices - Discrete devices - Part 5-4: Optoelectronic devices - Semiconductor lasers
• Effective Date: 05-Sep-2023

Overview

IEC 60747-5-4:2022 (with Amendment 1, 2024) is the IEC international standard that defines terminology, essential ratings and characteristics, and measurement methods for semiconductor lasers (optoelectronic devices). It consolidates device definitions, electrical and optical characteristic tables, and standardized test methods so manufacturers, test labs and system integrators can specify, measure and compare laser diodes consistently.

Key topics and requirements

• Terminology and definitions for physical concepts, device types, switching times, output/current parameters, spatial profiles and spectral characteristics. References updated to IEC 60050-845:2020 for lighting-related terms.
• Essential ratings and characteristics such as limiting (absolute maximum) values, electrical and optical characteristics, package and material details, and supplementary information used in datasheets (see Table 1 in Clause 4).
• Measurement methods covering:
  • Power measurement and calibration
  • Output stability: relative intensity noise (RIN), carrier-to-noise ratio (CNR) - corrected equation and measurement precautions added
  • Time-domain behaviour: switching times (rise/fall), small-signal cut-off frequency (f_c) - measurement references harmonized with ISO 11554
  • Lifetime testing and associated reference documents
  • Beam and spectral characteristics: polarization, radiation angle (updated terminology), half-intensity and 1/e2 widths, and spectral linewidth (new in this edition)
• Precautions and updates: amendment corrects CNR equation, adds equipment/arrangement cautions for CNR and beam-width measurements, and revises reference tables in annexes following current ISO publications.

Practical applications

• Create consistent, comparable datasheets and product specifications for semiconductor lasers.
• Define and harmonize test procedures in R&D and production test labs to ensure repeatable measurement of power, noise, modulation bandwidth and beam quality.
• Support qualification and lifetime testing for industrial, telecommunications, sensing/LiDAR, medical and consumer photonics products.
• Aid procurement, certification and compliance programs by providing agreed measurement metrics and limits.

Who should use this standard

• Laser diode and optoelectronic device manufacturers
• Test and calibration laboratories
• Systems and module integrators (telecom, sensing, industrial automation)
• Engineers writing datasheets, specifications or acceptance criteria
• Standards committees and compliance/certification bodies

Related standards

• IEC 60050-845 (International Electrotechnical Vocabulary - lighting terms)
• ISO 11554 (laser modulation/bandwidth measurement methods)
• Other ISO/IEC laser and beam-profile publications referenced in annexes

Using IEC 60747-5-4 ensures clarity and interoperability when specifying and measuring semiconductor laser performance, improving product quality and comparability across suppliers and industries.

Standards Content (Sample)

IEC 60747-5-4 ®
Edition 2.0 2022-04
INTERNATIONAL
STANDARD
Semiconductor devices –
Part 5-4: Optoelectronic devices – Semiconductor lasers
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
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IEC 60747-5-4 ®
Edition 2.0 2022-04
INTERNATIONAL
STANDARD
Semiconductor devices –
Part 5-4: Optoelectronic devices – Semiconductor lasers

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.080.01; 31.260 ISBN 978-2-8322-1100-7

– 2 – IEC 60747-5-4:2022 © IEC 2022
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
3.1 Physical concepts . 8
3.2 Types of devices . 9
3.3 General terms . 9
3.4 Terms related to ratings and characteristics . 10
3.4.1 Switching times . 10
3.4.2 Output and current characteristics . 12
3.5 Spatial profiles and spectral characteristics . 15
4 Essential rating and characteristics . 15
4.1 Type . 15
4.2 Semiconductor . 15
4.2.1 Material . 15
4.2.2 Structure . 15
4.3 Details of outline drawing and encapsulation. 16
4.4 Limiting values (absolute maximum ratings over the operating temperature
range, unless otherwise stated) . 16
4.5 Electrical and optical characteristics . 16
4.6 Supplementary information . 18
5 Measurement methods . 18
5.1 Power measurement . 18
5.2 Output stability . 18
5.2.1 Relative intensity noise . 18
5.2.2 Carrier-to-noise ratio . 18
5.2.3 Output power stability . 20
5.2.4 Output energy stability . 20
5.2.5 Temporal pulse shape . 20
5.3 Time domain profile . 20
5.3.1 Switching times . 20
5.3.2 Small signal cut-off frequency (f ) . 22
c
5.4 Lifetime . 22
5.5 Optical characteristics of the laser beam . 23
5.5.1 Polarization . 23
5.5.2 Half-intensity angle θ and 1/e -intensity angle θ 2 . 23
1/2 1/e
5.5.3 Half-intensity width D and 1/e -intensity width D 2 . 25
1/2 1/e
5.5.4 Spectral characteristics and other spatial profile . 26
Annex A (informative) Reference list of technical terms and definitions related to
spatial profile and spectral characteristics . 27
Annex B (informative) Reference list of measurement methods related to spatial
profile and spectral characteristics . 31
Annex C (informative) Reference list of technical terms and definitions, and
measurement methods, related to power measurement and lifetime . 32
Bibliography . 33

Figure 1 – Example of the device with window but without lens . 10
Figure 2 – Switching times . 12
Figure 3 – Threshold current of a laser diode . 14
Figure 4 – Basic circuit diagram . 19
Figure 5 – Basic circuits diagram . 21
Figure 6 – Typical pulse response diagram . 22
Figure 7 – Half-intensity angle . 23
Figure 8 – Relationship between the specified plane and the mechanical reference
plane . 23
Figure 9 – Basic measurement setup diagram . 24
Figure 10 – Measuring arrangement for D and D 2 . 25
1/2 1/e
Table 1 – Electrical and optical characteristics . 17

– 4 – IEC 60747-5-4:2022 © IEC 2022
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES –
Part 5-4: Optoelectronic devices –
Semiconductor lasers
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
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
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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 60747-5-4 has been prepared by subcommittee 47E: Discrete semiconductor devices, of
IEC technical committee 47: Semiconductor devices. It is an International Standard.
This second edition cancels and replaces the first edition published in 2006. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) References for the terms and definitions related to the lighting area, IEC 60050-845, are
revised based on IEC 60050-845:2020;
b) Emission angle is changed to radiation angle in 3.3.2;
c) Definitions of rise time and fall time in 3.4.1 are revised based on the publication IEC 60050-
521:2002;
d) Spectral linewidth is added to Table 1 in Clause 4;
e) Conditions for carrier-to-noise ratio of Table 1 in Clause 4 is amended.

f) Error in the equation for carrier-to-noise ratio in 5.2.2 is corrected;
g) Precaution against the equipment used for carrier-to-noise ratio measurement is added in
5.2.2;
h) Explanation for the measurement method of the small signal cut-off frequency in 5.3.2 of
the first edition is deleted because it has been defined in the latest version of ISO 11554;
i) Reference document for the lifetime in 5.4 is amended;
j) Precaution against the measuring arrangement used for the half-intensity width and 1/e -
intensity is added in 5.5.3;
k) Reference tables in Annex A, Annex B and Annex C are revised by following the latest
version of ISO publications.
The text of this International Standard is based on the following documents:
Draft Report on voting
47E/783/FDIS 47E/785/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.
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 60747 series, published under the general title Semiconductor
devices, 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 "http://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.
– 6 – IEC 60747-5-4:2022 © IEC 2022
INTRODUCTION
The first edition of this part of IEC 60747 was published in 2006 under close collaboration
between IEC TC 47 SC 47E (IEC TC 47 SC 47C at that moment) and ISO TC 172 SC 9. The
scope of IEC/TC47/SC47E includes laser diodes as one of the discrete semiconductor devices
while that of ISO/TC172/SC9 includes laser diodes as one of the laser and laser-related
equipment. Consequently, technical contents in this publication extend over IEC and ISO.
In order to harmonize the IEC and ISO laser-related standards in 1997, a joint working group
(JWG) consisted of the experts from both IEC SC 47E and ISO TC 172 SC 9 was established.
As a result of discussion, items based on the electrical and electronic technologies are dealt
with by subcommittee 47E of IEC technical committee 47, while optical characteristics of the
output beam are under the responsibility of subcommittee 9 of ISO technical committee 172.
This was agreed, after long discussion, in 2002 between subcommittee 47E of IEC technical
committee 47 and subcommittee 9 of ISO technical committee 172. Based on this agreement,
terms and definitions, and test and measurement methods for the optical beam parameters in
this part of IEC 60747-5-4 are referenced to the ISO standards that specify the topics.
The joint working group was disbanded in 2017. However, close co-operation and contact
between two groups is indispensable in order to avoid any conflicts and to keep harmonization
of IEC and ISO laser standards.
This second edition of IEC 60747-5-4 has been updated by following the revision and
amendments in the latest versions of laser standards of both IEC and ISO.

SEMICONDUCTOR DEVICES –
Part 5-4: Optoelectronic devices –
Semiconductor lasers
1 Scope
This part of IEC 60747 specifies the terminology, the essential ratings and characteristics as
well as the measuring methods of semiconductor lasers.
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 TR 62572-2, Fibre optic active components and devices – Reliability standards – Part 2:
Laser module degradation
ISO 11146-1, Lasers and laser-related equipment – Test methods for laser beam widths,
divergence angles and beam propagation ratios – Part 1: Stigmatic and simple astigmatic
beams
ISO 11554, Optics and photonics – Lasers and laser-related equipment – Test methods for laser
beam power, energy and temporal characteristics
ISO 12005, Lasers and laser-related equipment – Test methods for laser beam parameters –
Polarization
ISO 17526, Optics and optical instruments – Lasers and laser-related equipment – Lifetime of
lasers
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp

– 8 – IEC 60747-5-4:2022 © IEC 2022
3.1 Physical concepts
3.1.1
electromagnetic radiation,
phenomenon by which energy in the form of electromagnetic waves or photons emanates from
a source and is transferred through space
Note 1 to entry: The term “electromagnetic radiation” is also used for the electromagnetic waves or photons
produced (see IEV 705-02-01).
Note 2 to entry: The physical concepts of photons and electromagnetic waves are used to describe the same
phenomenon of transmission of radiant energy in different ways, depending on the nature of the interaction of the
energy with the physical world (wave-particle dualism).
[SOURCE: IEC 60050-702:1992/AMD5:2019, 702-02-07]
3.1.2
electromagnetic radiation,
energy that emanates from a source in the form of electromagnetic waves or photons and is
transferred through space
Note 1 to entry: The term “electromagnetic radiation” is also used for the phenomenon producing the
electromagnetic waves or photons (see IEV 702-02-07).
Note 2 to entry: The physical concepts of photons and electromagnetic waves are used to describe the same
phenomenon of transmission of radiant energy in different ways, depending on the nature of the interaction of the
energy with the physical world (wave-particle dualism).
[SOURCE: IEC 60050-705:1995/AMD4:2019, 705-02-01]
3.1.3
optical radiation
electromagnetic radiation at wavelengths between the region of transition to X-rays (λ ≈ 1 nm)
and the region of transition to radio waves (λ ≈ 1 mm)
Note 1 to entry: This entry was numbered 845-01-02 in IEC 60050-845:1987.
[SOURCE: IEC 60050-845:2020, 845-21-002]
3.1.4
light, noun
radiation that is considered from the point of view of its ability to excite the visual system
Note 1 to entry: The term "light" is sometimes used for optical radiation extending outside the visible range, but this
usage is not recommended.
Note 2 to entry: This entry was numbered 845-01-06 in IEC 60050-845:1987.
[SOURCE: IEC 60050-845:2020, 845-21-012]
3.1.5
light, noun
radiation within the spectral range of visible radiation
Note 1 to entry: Sometimes, the term "light" is also used in physics as a synonym of optical radiation, covering the
spectral range from 100 nm to 1 mm and sometimes even covering the X-ray spectral range. This misuse of the term
‘'light'' should be avoided.
[SOURCE: IEC 60050-845:2020, 845-21-013]

3.1.6
visible radiation
optical radiation (IEV 845-21-002) capable of causing a visual sensation directly
Note 1 to entry: There are no precise limits for the spectral range of visible radiation since they depend upon the
amount of radiant flux reaching the retina and the responsivity of the observer. The lower limit is generally taken
between 360 nm and 400 nm and the upper limit between 760 nm and 830 nm.
Note 2 to entry: This entry was numbered 845-01-03 in IEC 60050-845:1987.
Note 3 to entry: ISO 20473:2007 Optics and photonics – Spectral bands defines from 380 nm to 780 nm for the
range of visible radiation.
[SOURCE: IEC 60050-845:2020, 845-021-003, modified – Note 3 has been added.]
3.2 Types of devices
3.2.1
semiconductor laser
laser diode
semiconductor diode that emits coherent optical radiation through stimulated emission resulting
from the recombination of conduction electrons and holes when excited by an electric current
that exceeds the threshold current of the diode
Note 1 to entry: The laser diode is mounted on a submount or in a package with or without coupling means
(e.g. lens, fibre pigtail).
[SOURCE: IEC 60050-521:2002, 521-04-37, modified – The term "laser diode" has been
replaced by "semiconductor laser".]
3.3 General terms
3.3.1
beam axis
straight line connecting the centroids defined by the first spatial moments of the cross-sectional
power (energy) density distribution function at successive locations in the direction of
propagation (z) of the beam in a homogeneous medium
[SOURCE: ISO 11145:2018, 3.2.1]
3.3.2
optical port
geometrical configuration, referenced to an external plane or surface of the device, that is used
to specify the optical radiation emitted from an emitting device
EXAMPLE
Signification of annotations in the Figure 1:
= acceptance angle or radiation angle
α
= optical port with diameter D
D
Ref. = reference locus for the definition of the optical port

– 10 – IEC 60747-5-4:2022 © IEC 2022

Figure 1 – Example of the device with window but without lens
Note 1 to entry: The geometrical configuration should be specified by the manufacturer by means of geometrical
information, e.g:
– location, shape and size of the area of emission;
– angle of emission or acceptance;
– other parameters, e.g. numerical aperture of optical fibre;
– orientation of beam axis.
3.4 Terms related to ratings and characteristics
3.4.1 Switching times
Relation between the electrical input signal and the optical output signal is shown in Figure 2
with the indication of switching times.
3.4.1.1
rise time
t
r
time interval between the instants at which the magnitude of the pulse at the output terminals
reaches specified lower and upper limits respectively when the semiconductor device is being
switched from its non-conducting to its conducting state
Note 1 to entry: The lower and upper limits are usually 10 % and 90 % respectively of the final amplitude of the
output pulse.
[SOURCE: IEC 60050-521:2002, 521-05-22]
3.4.1.2
fall time
t
f
time interval between the instants at which the magnitude of the pulse at the output terminals
reaches specified upper and lower limits respectively when a semiconductor device is being
switched from its conducting to its non-conducting state
Note 1 to entry: The upper and lower limits are usually 90 % and 10 % respectively of the initial amplitude of the
output pulse.
[SOURCE: IEC 60050-521:2002, 521-05-24]

3.4.1.3
turn-on delay time
t
d(on)
time interval between the instant the electrical input signal reaches a specified level (10 %
unless otherwise stated) and the instant the optical output signal reaches a specifies level
(10 % of the steady-state maximum unless otherwise stated)
3.4.1.4
turn-on time
t
on
time interval between the instant the electrical input signal reaches a specified level (10 %
unless otherwise stated) and the instant the optical output signal reaches a specified level (90 %
of the steady-state maximum unless otherwise stated)
t = t + t
on d(on) r
3.4.1.5
turn-off delay time
t
d(off)
time interval between the instant the electrical input signal downs a specified level (90 % unless
otherwise stated) and the instant the optical output signal downs a specifies level (90 % of the
steady-state maximum unless otherwise stated)
3.4.1.6
turn-off time
t
off
time interval between the instant the electrical input signal downs a specified level (90 % unless
otherwise stated) and the instant the optical output signal downs a specified level (10 % of the
steady-state maximum unless otherwise stated).
t = t + t
off d(off) f
– 12 – IEC 60747-5-4:2022 © IEC 2022

Figure 2 – Switching times
NOTE Lower and upper specified values indicate 10 % and 90 %, respectively, unless otherwise stated.
3.4.2 Output and current characteristics
3.4.2.1
output power,
P
radiant power transferred from the semiconductor laser through the optical port
[SOURCE: ISO 11145:2018, 3.18, modified – The symbol “R(f)“has been replaced by “RIN”. ]
3.4.2.2
radiant flux
radiant power
Φ
e
change in radiant energy with time
dQ
e
Φ =
e
dt
where Q is the radiant energy emitted, transferred or received, and t is time
e
Note 1 to entry: The corresponding photometric quantity is "luminous flux". The corresponding quantity for photons
is "photon flux".
Note 2 to entry: The term "radiant flux" is the preferred term for most radiometric applications, with the notable
exception of laser radiometry where the term "radiant power" is more commonly used.
Note 3 to entry: The radiant flux is expressed in watt (W).

Note 4 to entry: This entry was numbered 845-01-24 in IEC 60050-845:1987.
[SOURCE: IEC 60050-845:2020, 845-21-038]
3.4.2.3
differential output power efficiency
η
d
output power efficiency for small-signal modulation:
η = dP/dI
d F
Note 1 to entry: Dimension of η is W/A.
d
Note 2 to entry: The term "small-signal modulation efficacy" is used as a synonym.
Note 3 to entry: Differential output power quantum efficiency = q/(hν). η is also applicable,
d
where
q is the electron charge,
ν is the optical frequency,
h is equal to 6,626 070 15 × 10-34 Js (Planck’s constant).
3.4.2.4
threshold current,
I
TH
forward current derived from one of the following two methods:
a) derivative threshold current I
TH(D)
forward current at which the second derivative of the curve showing output power P versus
forward current I has its first maximum [see Figure 3 a)];
F
b) extrapolated threshold current
forward current at which the extrapolated two straight lines of the stimulated emission and the
spontaneous emission cross each other [see Figure 3 b)].

– 14 – IEC 60747-5-4:2022 © IEC 2022

a) Derivative threshold current of a laser diode

b) Extrapolated threshold current of a laser diode
Figure 3 – Threshold current of a laser diode
3.4.3 Noise characteristics (of a semiconductor laser)
3.4.3.1
relative intensity noise
RIN
R(f)
ratio of the mean square radiant power fluctuations to the mean square radiant power,
normalized to a frequency band of unit width, for radiant power P(f) as a function of frequency f
ΔP f
( )
Rf =
( )
Δf
Pf
( )
Note 1 to entry: The relative intensity noise as defined above is strictly “relative intensity noise spectral density”,
but usually simplify referred to as RIN.
[SOURCE: ISO 11145:2018, 3.18]
3.4.3.2
carrier-to-noise ratio
C/N
quotient of:
– the mean square radiant power at the specified frequency, to
– t
...

IEC 60747-5-4 ®
Edition 2.1 2024-12
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
colour
inside
Semiconductor devices –
Part 5-4: Optoelectronic devices – Semiconductor lasers

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

IEC Secretariat Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform IEC Products & Services Portal - products.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews, graphical symbols and the glossary.
committee, …). It also gives information on projects, replaced With a subscription you will always have access to up to date
and withdrawn publications. content tailored to your needs.

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IEC 60747-5-4 ®
Edition 2.1 2024-12
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
colour
inside
Semiconductor devices –
Part 5-4: Optoelectronic devices – Semiconductor lasers
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.080.01; 31.260 ISBN 978-2-8327-0106-5
REDLINE VERSION – 2 – IEC 60747-5-4:2022+AMD1:2024 CSV
© IEC 2024
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
3.1 Physical concepts . 8
3.2 Types of devices . 9
3.3 General terms . 9
3.4 Terms related to ratings and characteristics . 10
3.4.1 Switching times . 10
3.4.2 Output and current characteristics . 12
3.5 Spatial profiles and spectral characteristics . 15
4 Essential rating and characteristics . 15
4.1 Type . 15
4.2 Semiconductor . 16
4.2.1 Material . 16
4.2.2 Structure . 16
4.3 Details of outline drawing and encapsulation. 16
4.4 Limiting values (absolute maximum ratings over the operating temperature
range, unless otherwise stated) . 16
4.5 Electrical and optical characteristics . 16
4.6 Supplementary information . 18
5 Measurement methods . 18
5.1 Power measurement . 18
5.2 Output stability . 18
5.2.1 Relative intensity noise . 18
5.2.2 Carrier-to-noise ratio . 18
5.2.3 Output power stability . 20
5.2.4 Output energy stability . 20
5.2.5 Temporal pulse shape . 20
5.3 Time domain profile . 20
5.3.1 Switching times . 20
5.3.2 Small signal cut-off frequency (f ) . 22
c
5.4 Lifetime . 22
5.5 Optical characteristics of the laser beam . 23
5.5.1 Polarization . 23
5.5.2 Half-intensity angle θ and 1/e -intensity angle θ 2 . 23
1/2 1/e
5.5.3 Half-intensity width D and 1/e -intensity width D 2 . 25
1/2 1/e
5.5.4 Spectral characteristics and other spatial profile . 26
Annex A (informative) Reference list of technical terms and definitions related to
spatial profile and spectral characteristics . 27
Annex B (informative) Reference list of measurement methods related to spatial
profile and spectral characteristics . 31
Annex C (informative) Reference list of technical terms and definitions, and
measurement methods, related to power measurement and lifetime . 32
Bibliography . 33

© IEC 2024
Figure 1 – Example of the device with window but without lens . 10
Figure 2 – Switching times . 12
Figure 3 – Threshold current of a laser diode . 14
Figure 4 – Basic circuit diagram . 19
Figure 5 – Basic circuits diagram . 21
Figure 6 – Typical pulse response diagram . 22
Figure 7 – Half-intensity angle . 23
Figure 8 – Relationship between the specified plane and the mechanical reference
plane . 23
Figure 9 – Basic measurement setup diagram . 24
Figure 10 – Measuring arrangement for D and D 2 . 25
1/2 1/e
Table 1 – Electrical and optical characteristics . 17

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© IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SEMICONDUCTOR DEVICES –
Part 5-4: Optoelectronic devices –
Semiconductor lasers
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
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as "IEC Publication(s)"). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
This consolidated version of the official IEC Standard and its amendment has been
prepared for user convenience.
IEC 60747-5-4 edition 2.1 contains the second edition (2022-04) [documents 47E/783/FDIS
and 47E/785/RVD] and its amendment 1 (2024-12) [documents 47E/819/CDV and
47E/841/RVC].
In this Redline version, a vertical line in the margin shows where the technical content is
modified by amendment 1. Additions are in green text, deletions are in strikethrough red
text. A separate Final version with all changes accepted is available in this publication.

© IEC 2024
IEC 60747-5-4 has been prepared by subcommittee 47E: Discrete semiconductor devices, of
IEC technical committee 47: Semiconductor devices. It is an International Standard.
This second edition cancels and replaces the first edition published in 2006. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) References for the terms and definitions related to the lighting area, IEC 60050-845, are
revised based on IEC 60050-845:2020;
b) Emission angle is changed to radiation angle in 3.3.2;
c) Definitions of rise time and fall time in 3.4.1 are revised based on the publication IEC 60050-
521:2002;
d) Spectral linewidth is added to Table 1 in Clause 4;
e) Conditions for carrier-to-noise ratio of Table 1 in Clause 4 is amended.
f) Error in the equation for carrier-to-noise ratio in 5.2.2 is corrected;
g) Precaution against the equipment used for carrier-to-noise ratio measurement is added in
5.2.2;
h) Explanation for the measurement method of the small signal cut-off frequency in 5.3.2 of
the first edition is deleted because it has been defined in the latest version of ISO 11554;
i) Reference document for the lifetime in 5.4 is amended;
j) Precaution against the measuring arrangement used for the half-intensity width and 1/e -
intensity is added in 5.5.3;
k) Reference tables in Annex A, Annex B and Annex C are revised by following the latest
version of ISO publications.
The language used for the development of this International Standard is English.
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 60747 series, published under the general title Semiconductor
devices, can be found on the IEC website.
The committee has decided that the contents of this document and its amendment 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, or
• revised.
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 document using a colour printer.

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© IEC 2024
INTRODUCTION
The first edition of this part of IEC 60747 was published in 2006 under close collaboration
between IEC TC 47 SC 47E (IEC TC 47 SC 47C at that moment) and ISO TC 172 SC 9. The
scope of IEC/TC47/SC47E includes laser diodes as one of the discrete semiconductor devices
while that of ISO/TC172/SC9 includes laser diodes as one of the laser and laser-related
equipment. Consequently, technical contents in this publication extend over IEC and ISO.
In order to harmonize the IEC and ISO laser-related standards in 1997, a joint working group
(JWG) consisted of the experts from both IEC SC 47E and ISO TC 172 SC 9 was established.
As a result of discussion, items based on the electrical and electronic technologies are dealt
with by subcommittee 47E of IEC technical committee 47, while optical characteristics of the
output beam are under the responsibility of subcommittee 9 of ISO technical committee 172.
This was agreed, after long discussion, in 2002 between subcommittee 47E of IEC technical
committee 47 and subcommittee 9 of ISO technical committee 172. Based on this agreement,
terms and definitions, and test and measurement methods for the optical beam parameters in
this part of IEC 60747-5-4 are referenced to the ISO standards that specify the topics.
The joint working group was disbanded in 2017. However, close co-operation and contact
between two groups is indispensable in order to avoid any conflicts and to keep harmonization
of IEC and ISO laser standards.
This second edition of IEC 60747-5-4 has been updated by following the revision and
amendments in the latest versions of laser standards of both IEC and ISO.

© IEC 2024
SEMICONDUCTOR DEVICES –
Part 5-4: Optoelectronic devices –
Semiconductor lasers
1 Scope
This part of IEC 60747 specifies the terminology, the essential ratings and characteristics as
well as the measuring methods of semiconductor lasers.
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 TR 62572-2, Fibre optic active components and devices – Reliability standards – Part 2:
Laser module degradation
ISO 11146-1, Lasers and laser-related equipment – Test methods for laser beam widths,
divergence angles and beam propagation ratios – Part 1: Stigmatic and simple astigmatic
beams
ISO 11554, Optics and photonics – Lasers and laser-related equipment – Test methods for laser
beam power, energy and temporal characteristics
ISO 12005, Lasers and laser-related equipment – Test methods for laser beam parameters –
Polarization
ISO 17526, Optics and optical instruments – Lasers and laser-related equipment – Lifetime of
lasers
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp

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© IEC 2024
3.1 Physical concepts
3.1.1
electromagnetic radiation,
phenomenon by which energy in the form of electromagnetic waves or photons emanates from
a source and is transferred through space
Note 1 to entry: The term “electromagnetic radiation” is also used for the electromagnetic waves or photons
produced (see IEV 705-02-01).
Note 2 to entry: The physical concepts of photons and electromagnetic waves are used to describe the same
phenomenon of transmission of radiant energy in different ways, depending on the nature of the interaction of the
energy with the physical world (wave-particle dualism).
[SOURCE: IEC 60050-702:1992/AMD5:2019, 702-02-07]
3.1.2
electromagnetic radiation,
energy that emanates from a source in the form of electromagnetic waves or photons and is
transferred through space
Note 1 to entry: The term “electromagnetic radiation” is also used for the phenomenon producing the
electromagnetic waves or photons (see IEV 702-02-07).
Note 2 to entry: The physical concepts of photons and electromagnetic waves are used to describe the same
phenomenon of transmission of radiant energy in different ways, depending on the nature of the interaction of the
energy with the physical world (wave-particle dualism).
[SOURCE: IEC 60050-705:1995/AMD4:2019, 705-02-01]
3.1.3
optical radiation
electromagnetic radiation at wavelengths between the region of transition to X-rays (λ ≈ 1 nm)
and the region of transition to radio waves (λ ≈ 1 mm)
Note 1 to entry: This entry was numbered 845-01-02 in IEC 60050-845:1987.
[SOURCE: IEC 60050-845:2020, 845-21-002]
3.1.4
light, noun
radiation that is considered from the point of view of its ability to excite the visual system
Note 1 to entry: The term "light" is sometimes used for optical radiation extending outside the visible range, but this
usage is not recommended.
Note 2 to entry: This entry was numbered 845-01-06 in IEC 60050-845:1987.
[SOURCE: IEC 60050-845:2020, 845-21-012]
3.1.5
light, noun
radiation within the spectral range of visible radiation
Note 1 to entry: Sometimes, the term "light" is also used in physics as a synonym of optical radiation, covering the
spectral range from 100 nm to 1 mm and sometimes even covering the X-ray spectral range. This misuse of the term
‘'light'' should be avoided.
[SOURCE: IEC 60050-845:2020, 845-21-013]

© IEC 2024
3.1.6
visible radiation
optical radiation (IEV 845-21-002) capable of causing a visual sensation directly
Note 1 to entry: There are no precise limits for the spectral range of visible radiation since they depend upon the
amount of radiant flux reaching the retina and the responsivity of the observer. The lower limit is generally taken
between 360 nm and 400 nm and the upper limit between 760 nm and 830 nm.
Note 2 to entry: This entry was numbered 845-01-03 in IEC 60050-845:1987.
Note 3 to entry: ISO 20473:2007 Optics and photonics – Spectral bands defines from 380 nm to 780 nm for the
range of visible radiation.
[SOURCE: IEC 60050-845:2020, 845-021-003, modified – Note 3 has been added.]
3.2 Types of devices
3.2.1
semiconductor laser
laser diode
semiconductor diode that emits coherent optical radiation through stimulated emission resulting
from the recombination of conduction electrons and holes when excited by an electric current
that exceeds the threshold current of the diode
Note 1 to entry: The laser diode is mounted on a submount or in a package with or without coupling means
(e.g. lens, fibre pigtail).
[SOURCE: IEC 60050-521:2002, 521-04-37, modified – The term "laser diode" has been
replaced by "semiconductor laser".]
3.3 General terms
3.3.1
beam axis
straight line connecting the centroids defined by the first spatial moments of the cross-sectional
power (energy) density distribution function at successive locations in the direction of
propagation (z) of the beam in a homogeneous medium
[SOURCE: ISO 11145:2018, 3.2.1]
3.3.2
optical port
geometrical configuration, referenced to an external plane or surface of the device, that is used
to specify the optical radiation emitted from an emitting device
EXAMPLE
Signification of annotations in the Figure 1:
= acceptance angle or radiation angle
α
= optical port with diameter D
D
Ref. = reference locus for the definition of the optical port

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© IEC 2024
Figure 1 – Example of the device with window but without lens
Note 1 to entry: The geometrical configuration should be specified by the manufacturer by means of geometrical
information, e.g:
– location, shape and size of the area of emission;
– angle of emission or acceptance;
– other parameters, e.g. numerical aperture of optical fibre;
– orientation of beam axis.
3.4 Terms related to ratings and characteristics
3.4.1 Switching times
Relation between the electrical input signal and the optical output signal is shown in Figure 2
with the indication of switching times.
3.4.1.1
rise time
t
r
time interval between the instants at which the magnitude of the pulse at the output terminals
reaches specified lower and upper limits respectively when the semiconductor device is being
switched from its non-conducting to its conducting state
Note 1 to entry: The lower and upper limits are usually 10 % and 90 % respectively of the final amplitude of the
output pulse.
[SOURCE: IEC 60050-521:2002, 521-05-22]
3.4.1.2
fall time
t
f
time interval between the instants at which the magnitude of the pulse at the output terminals
reaches specified upper and lower limits respectively when a semiconductor device is being
switched from its conducting to its non-conducting state
Note 1 to entry: The upper and lower limits are usually 90 % and 10 % respectively of the initial amplitude of the
output pulse.
[SOURCE: IEC 60050-521:2002, 521-05-24]

© IEC 2024
3.4.1.3
turn-on delay time
t
d(on)
time interval between the instant the electrical input signal reaches a specified level (10 %
unless otherwise stated) and the instant the optical output signal reaches a specifies level
(10 % of the steady-state maximum unless otherwise stated)
3.4.1.4
turn-on time
t
on
time interval between the instant the electrical input signal reaches a specified level (10 %
unless otherwise stated) and the instant the optical output signal reaches a specified level (90 %
of the steady-state maximum unless otherwise stated)
t = t + t
on d(on) r
3.4.1.5
turn-off delay time
t
d(off)
time interval between the instant the electrical input signal downs a specified level (90 % unless
otherwise stated) and the instant the optical output signal downs a specifies level (90 % of the
steady-state maximum unless otherwise stated)
3.4.1.6
turn-off time
t
off
time interval between the instant the electrical input signal downs a specified level (90 % unless
otherwise stated) and the instant the optical output signal downs a specified level (10 % of the
steady-state maximum unless otherwise stated).
t = t + t
off d(off) f
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© IEC 2024
Figure 2 – Switching times
NOTE Lower and upper specified values indicate 10 % and 90 %, respectively, unless otherwise stated.
3.4.2 Output and current characteristics
3.4.2.1
output power,
P
radiant power transferred from the semiconductor laser through the optical port
[SOURCE: ISO 11145:2018, 3.18, modified – The symbol “R(f)“has been replaced by “RIN”. ]
3.4.2.2
radiant flux
radiant power
Φ
e
change in radiant energy with time
dQ
e
Φ =
e
dt
where Q is the radiant energy emitted, transferred or received, and t is time
e
Note 1 to entry: The corresponding photometric quantity is "luminous flux". The corresponding quantity for photons
is "photon flux".
Note 2 to entry: The term "radiant flux" is the preferred term for most radiometric applications, with the notable
exception of laser radiometry where the term "radiant power" is more commonly used.
Note 3 to entry: The radiant flux is expressed in watt (W).

© IEC 2024
Note 4 to entry: This entry was numbered 845-01-24 in IEC 60050-845:1987.
[SOURCE: IEC 60050-845:2020, 845-21-038]
3.4.2.3
differential output power efficiency
η
d
output power efficiency for small-signal modulation:
η = dP/dI
d F
Note 1 to entry: Dimension of η is W/A.
d
Note 2 to entry: The term "small-signal modulation efficacy" is used as a synonym.
Note 3 to entry: Differential output power quantum efficiency = q/(hν). η is also applicable,
d
where
q is the electron charge,
ν is the optical frequency,
h is equal to 6,626 070 15 × 10-34 Js (Planck’s constant).
3.4.2.4
threshold current,
I
TH
forward current derived from one of the following two methods:
a) derivative threshold current I
TH(D)
forward current at which the second derivative of the curve showing output power P versus
forward current I has its first maximum [see Figure 3 a)];
F
b) extrapolated threshold current
forward current at which the extrapolated two straight lines of the stimulated emission and the
spontaneous emission cross each other [see Figure 3 b)].

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© IEC 2024
a) Derivative threshold current of a laser diode

b) Extrapolated threshold current of a laser diode
Figure 3 – Threshold current of a laser diode
3.4.3 Noise characteristics (of a semiconductor laser)
3.4.3.1
relative intensity noise
RIN
R(f)
ratio of the mean square radiant power fluctuations to the mean square radiant power,
normalized to a frequency band of unit width, for radiant power P(f) as a function of frequency f
ΔP f
( )
Rf =
( )
Δf
Pf
( )
Note 1 to entry: The relative intensity noise as defined above is strictly “relative intensity noise spectral density”,
but usually simplify referred to as RIN.
ratio of the radiant power mean square fluctuation to the square of the mean radiant power,
normalized to a frequency band of unit width
∆P f
( )
R f ⋅
( )
∆f
P
where ∆f is the noise equivalent bandwidth
Note 1 to entry: The relative intensity noise as defined above is strictly "spectral relative intensity noise", but usually
simplify referred to as RIN.
=
© IEC 2024
[SOURCE: ISO 11145:2018, 3.18]
3.4.3.2
carrier-to-noise ratio
C/N
quotient of:
– the mean square radiant power at the specified frequency, to
– the mean square radiant power fluctuations normalized to a frequency band of unit width
centered on the carrier frequency
3.4.4
small signal cut-off frequency
f
c
frequency at which the laser power output modulation drops to half the value obtained at low
frequencies when applying small, constant input power modulation and increasing the
frequency
[SOURCE: ISO 11554:2017, 3.2]
3.4.5
half-intensity angle
θ
1/2
in a radiation diagram, angle within which the radiant intensity is greater than or equal to half
of the maximum intensity
3.4.6
1/e -intensity angle
θ
1/e
in a radiation diagram, angle within which the radiant intensity is greater than or equal to 1/e
of the maximum intensity
3.4.7
half-intensity width
D
1/2
full width of a beam, within which the power density is greater than or equal to half of the
maximum power density at a specified position z along the beam propagation direction
3.4.8
1/e -intensity width
D
1/e
full width of a beam, within which the power density is greater than or equal to 1/e of the
maximum
3.5 Spatial profiles and spectral characteristics
Reference list of technical terms and definitions related to spatial profiles and spectral
characteristics are defined in several ISO documents as shown in Annex A (informative).
4 Essential rating and characteristics
4.1 Type
Ambient-rated or case-rated semiconductor lasers shall be stated.

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© IEC 2024
4.2 Semiconductor
4.2.1 Material
Material such as GaAlAs, InGaAsP, InGaAlP, InGaAlN, GaN, InGaN, etc. shall be provided.
4.2.2 Structure
Structure such as (single or multi) quantum well, quantum dots, surface emitting, etc. shall be
provided.
4.3 Details of outline drawing and encapsulation
a) IEC and/or national reference number of the outline drawing;
b) method of encapsulation: glass/metal/plastic/other;
c) terminal identification and indication of any electrical connection between a terminal and the
case;
d) characteristics of the optical port: orientation relative to mechanical axes, position relative
to mechanical axes, area, numerical aperture.
NOTE Numerical aperture is essential depending on the application.
4.4 Limiting values (absolute maximum ratings over the operating temperature range,
unless otherwise stated)
a) minimum and maximum storage temperatures (T )
stg
b) minimum and maximum operating temperatures
– ambient or case temperature (T or T );
amb case
– submount temperature, where appropriate (T ).
sub
c) maximum soldering temperature (soldering time and minimum distance to case) (T )
sld
d) maximum reverse voltage (V )
RM
e) additional informations
f) one or more of the following at an ambient or case temperature of 25 °C together with a
derating curve or derating factor with temperature
– maximum continuous forward current (I );
FM
– maximum continuous output power (P );
M
– maximum pulsed forward current at stated frequency and pulse duration (I );
FM
– maximum pulsed output power at stated frequency and pulse duration (P ).
M
4.5 Electrical and optical characteristics

Output power shall be specified as continuous or pulsed as appropriate to the device. ∆I
F
indicates a forward current above the measured threshold current I of the device being
TH
measured. Electrical and optical characteristics are referenced in following Table 1.

© IEC 2024
Table 1 – Electrical and optical characteristics
Conditions at T
amb
Specifications
or T = 25 °C,
case
Characteristics Symbol
unless otherwise
a
Required Requirement
Options
stated
Forward voltage I or P specified V max.
×
F F
I
Threshold current × min. and max.
TH
Output power at threshold I P max.
×
TH TH
Forward current above P specified ∆I × max.
F
threshold
Forward current above P specified, ∆I × max.
F
threshold at T max T = T max
case case
or T max or T max
amb amb
Differential output power min. and max.
P or ∆I specified η ×
F d
efficiency
Peak emission wavelength min. and max.
∆I or P specified λ ×
F p
Central wavelength min. and max.
∆I or P specified λ ×
F c
Spectral bandwidth min. and max.
∆I or P specified ∆λ ×
F
or:
RMS spectral bandwidth ∆I or P specified ∆λ × min. and max.
F rms
or:
Number of longitudinal modes n min. and max.
∆I or P specified ×
m
F
within a specified bandwidth
min. and max.
×
s
and mode spacing in the Bandwidth specified
m
wavelength domain
Spectral linewidth ∆I or P specified ∆λ × max.
F L
Side-mode suppression ratio ∆I or P specified SMSR × min.
F
b, c ∆I or P specified θ σ × min.
Divergence angles
F
d
or:
∆I or P specified θ (1)
F 1/2
×
max.
Half-intensity angle in two
e
reference planes
θ (2)
×
1/2
c
specified planes
specified
d
or: ∆I or P specified 2
θ (1)
F
1/e
×
max.
1/e -intensity angle in two e
reference planes
θ (2)
×
1/e
c
specified planes specified
Misalignment angle max.
∆I or P specified ∆θ ×
F
d
Half-intensity width at the min. and max.
∆I or P specified, D (x) ×
F 1/2
facet of laser diode
reference axes specified
e ×
D (y)
1/2
d
or: ∆I or P specified, × min. and max.
D (x)
F
1/e
reference axes specified
×
1/e -intensity width at the e
D (y)
1/e
facet of laser diode
f
Astigmatic difference ∆I or P specified,
F
d
max.
×
A
reference axes specified
Rise time and fall time
Bias conditions (∆I or
F
t , t × max.
∆P) specified r f
or:
×
Turn-on time and Input pulse current, t , t max.
on off
turn-off time width and duty specified

REDLINE VERSION – 18 – IEC 60747-5-4:2022+AMD1:2024 CSV
© IEC 2024
Conditions at T
amb
Specifications
or T = 25 °C,
case
Characteristics Symbol
unless otherwise
a
Required Options Requirement
stated
Small-signal cut-off frequency ∆I or P specified f × min.
F c
Relative intensity noise P, f , ∆f P, f , ∆f R(f) × max.
o N 0
specified
Carrier-to-noise ratio P, f , ∆f, f C/N × max.
specified,
o m
modulation format
specified
Total capacitance C max.
∆I or P, or V specified ×
tot
F R
frequency specified
Total inductance ∆I or P, or V specified L × max.
F R tot
frequency specified
S parameter ∆I or P specified S × max.
11 F 11
frequency specified
a
Options should be specified appropriate to applications.
b
Only divergence angle according to ISO 11145 should be used. However, for the time being, data sheets may
use both divergence angle and half-intensity angle. Manufacturers and users shall determine the parameter
depending on applications.
c
Care should be taken in confusing the divergence angle with the half-intensity angle, because they are defined
based on the completely different concept.
d
Parallel to the reference plane.
e
Perpendicular to the reference plane.
f
The astigmatic difference shall be derived based on ISO 11146-1.

4.6 Supplementary information
Temperature dependence of emission wavelength should be provided as a supplementary
information.
5 Measurement methods
5.1 Power measurement
Power measurement shall be performed by using the method defined in ISO 11554.
5.2 Output stability
5.2.1 Relative intensity noise
Relative intensity noise measurement shall be performed by using the method defined in
ISO 11554.
5.2.2 Carrier-to-noise ratio
a) Purpose
To measure the carrier-to-noise ratio (C/N) of semiconductor lasers at a specified output
power level in continuous wave (cw) under specified modulation conditions.
b) Circuit diagram
The measurement circuit diagram for the carrier-to-noise ratio is shown in Figure 4.

© IEC 2024
Figure 4 – Basic circuit diagram
c) Circuit description
CS = DC current source
D = device being measured
G = AC generator
T = bias T or passive biasing circuit
L = focusing lens systems
PD = photodetector
A = current measuring instrument
AMP(f ) = amplifier suitable for use at frequency f
m m
W1 = power meter
AMP(f ) = amplifier and filter suitable for use at frequency f
o o
W2 = power meter
N = impedance matching and signal dividing network
C
d) Precautions to be observed
Specifications of each equipment that is used for the measurement should be carefully
examined in order to ensure the accuracy of the test required.
The associated "photodetector + ammeter" shall be calibrated corresponding to the output
power of D over the required wavelength range.
The focusing systems shall be designed:
– to avoid radiation being reflected back into the laser diode or the laser module;
– to bring to focus the optical port of the device being measured onto the optical port of
the photodetector.
e) Measurement procedure
The specified supply and drive conditions are applied to the device being measured, D.
The photocurrent (I ) resulting from the illumination (P specified) of the photodetector is
ph
measured first and noted. RF modulation is applied to the device being measured through
the biasing circuit: specified modulation format with carrier frequency f . The electrical
m
at frequency f is measured on the power meter W1. This electrical power P is
power P
1 m 1
related to the modulated output power squared as follows:
P
ΔΦ =
( )
m
SR−
c
REDLINE VERSION – 20 – IEC 60747-5-4:2022+AMD1:2024 CSV
© IEC 2024
where
S is the responsivity of the photodetector PD;
R is the load resistance of PD [input of AMP(f )].
c m
The noise electrical power N at frequency f in the frequency band ∆f is measured on the
tot o
power meter W2 (f should be as close as technically possible to f ). This is the sum of the
o m
pure shot noise associated with the photocurrent I and the excess noise due to the
ph
radiation source intensity fluctuations. The pure shot noise shall be measured under the
same illumination conditions (same I ) using a "radiation source with broad optical
ph
spectrum". The electrical noise power corresponding to the pure shot noise equivalent
output power fluctuations (N ) can be measured with W2:
s
ΔΦ
C ( ) P

m
or

N ( NN− )

lin ΔΦ tot s
e
CC
 
=10log
 10 
NN
 
lin
f) Specified conditions
– ambient, case or submount temperature;
– measurement bias conditions (P, I or ∆I );
F F
– frequency and bandwidth (f , ∆f);
o
– carrier frequency (f );
m
– modulation format.
5.2.3 Output power stability
Output power stability measurement shall be performed by using the method defined in
ISO 11554.
5.2.4 Output energy stability
Output energy stability measurement shall be performed by using the method defined in
ISO 11554.
5.2.5 Temporal pulse shape
Temporal pulse shape measurement shall be performed by using the method defined in
ISO 11554. Evaluation for the temporal pulse shape measurement should coincide with the
description in ISO 11554:2017, 8.6.
5.3 Time domain profile
5.3.1 Switching times
5.3.1.1 Rise time and fall time
Rise time and fall time measurements shall be performed by using the method defined in
ISO 11554. Evaluation for the rise time and fall time measurements should coincide with the
description in ISO 11554:2017, 8.6.
==
© IEC 2024
5.3.1.2 Turn-on delay time and turn-off delay time
a) Purpose
To measure the turn-on time t (turn-on delay time t + rise time t ) and turn-off time t
on d(on) r off
(turn-off delay time t + fall time t ) of semiconductor lasers under specified conditions.
d(off) f
b) Circuit diagram
The measurement circuit diagram for turn-on and turn-off delay times is shown in Figure 5.

Figure 5 – Basic circuits diagram
c) Circuit description
G = current pulse generator, with high impedance
G = d. c. current bias source
= d. c. voltage bias source
G
R = resistance for matching the impedance with generator
d
D = device being measured
PD = photodiode
R = load resistance
L
M = measuring instrument
Syn. = synchronization signal
d) Precautions to be observed
The switching time of the photodiode, the delay time of the circuit and measuring instrume
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