EN ISO 11979-1:2026

Ophthalmic implants - Intraocular lenses - Part 1: Vocabulary (ISO 11979-1:2026)

This document contains definitions of terms related to intraocular lenses as well as definitions related to the methods used to evaluate these IOLs.
NOTE            The terms are listed in the alphabetical order of the English terms.

Ophthalmische Implantate - Intraokularlinsen - Teil 1: Vokabular (ISO 11979-1:2026)

Dieses Dokument enthält Definitionen von Benennungen in Zusammenhang mit Intraokularlinsen und phaken Intraokularlinsen sowie Definitionen in Zusammenhang mit den Verfahren für die Bewertung dieser IOL.
ANMERKUNG   Die Begriffe sind in der alphabetischen Reihenfolge der englischsprachigen Fassung dieses Dokuments angegeben.

Implants ophtalmiques - Lentilles intraoculaires - Partie 1: Vocabulaire (ISO 11979-1:2026)

Le présent document contient des définitions de termes relatifs aux lentilles intraoculaires et de méthodes d’essai utilisées pour les évaluer.
NOTE            Les termes sont présentés dans l’ordre alphabétique des termes anglais.

Očesni vsadki (implantati) - Intraokularne leče - 1. del: Slovar (ISO 11979-1:2026)

Ta dokument vsebuje definicije izrazov, povezanih z intraokularnimi lečami, kot tudi definicije, povezane z metodami, uporabljenimi za ocenjevanje teh IOL (intraokularnih leč).
OPOMBA Izrazi so navedeni po abecednem vrstnem redu angleških izrazov.

General Information

• Status: Published
• Publication Date: 10-Mar-2026
• ICS: 01.040.11 - Health care technology (Vocabularies)
• ICS: 11.040.70 - Ophthalmic equipment
• Technical Committee: CEN/TC 170 - Ophthalmic optics
• Drafting Committee: CEN/TC 170 - Ophthalmic optics
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 11-Mar-2026
• Completion Date: 11-Mar-2026
• Ref Project: SIST EN ISO 11979-1:2026 - Ophthalmic implants - Intraocular lenses - Part 1: Vocabulary (ISO 11979-1:2026)

Relations

• Replaces: EN ISO 11979-1:2018 - Ophthalmic implants - Intraocular lenses - Part 1: Vocabulary (ISO 11979-1:2018)
• Effective Date: 19-Jan-2023
• Consolidated By: ISO 11979-1:2026 - Ophthalmic implants — Intraocular lenses — Part 1: Vocabulary
• Effective Date: 12-Feb-2026

Overview

EN ISO 11979-1:2026 sets forth standardized terminology for intraocular lenses (IOLs), a crucial category of ophthalmic implants. This international standard, developed by CEN in collaboration with ISO, serves as Part 1 of a broader series dedicated to IOLs and focuses specifically on vocabulary and definitions. By providing clear and uniform definitions, EN ISO 11979-1 facilitates consistent communication among manufacturers, healthcare providers, regulatory authorities, and researchers in the field of ophthalmic implants.

The vocabulary encompasses terms relating to IOL types, properties, components, evaluation methods, clinical scenarios, and aspects of manufacturing and packaging. The terms are listed in alphabetical order for ease of reference, and the definitions are crafted to ensure clarity and alignment with both clinical and regulatory needs.

Key Topics

• Comprehensive IOL Definitions

  • Types of intraocular lenses: monofocal, multifocal, toric, accommodating, extended depth of focus, and phakic IOLs
  • Key components: optic, haptic, body, closed-loop, and open-loop designs

• Evaluation and Performance Terms

  • Dioptric power, base power, addition power, effective focal length, and spherical equivalent power
  • Clinical metrics: visual acuity, subjective and objective refraction
  • Durability: dynamic fatigue, stability, shelf-life, and photostability

• Manufacturing and Packaging

  • Definitions related to manufacturing date, sterilization load, package system, primary and protective packaging
  • Device tracking: device history record, patient implant card (PIC), patient information leaflet (PIL)

• Preclinical and Clinical Assessment

  • Test procedures and reference to related assessments (e.g., ocular/non-ocular implantation tests, Nd-YAG laser exposure test)
  • Definitions supporting clinical investigations and adverse event tracking

Applications

EN ISO 11979-1:2026 provides practical value across the ophthalmic sector by enabling:

• Standardized Documentation: Manufacturers can align product specifications and labelling with internationally recognized terminology, supporting regulatory submission and market approval.
• Enhanced Clinical Practice: Ophthalmic surgeons and clinical staff benefit from common definitions when selecting and implanting IOLs, promoting patient safety and treatment efficacy.
• Regulatory Consistency: National and international authorities leverage the standard’s definitions to harmonize evaluation criteria and post-market surveillance.
• Research and Development: R&D teams utilize precise terms during product design, testing, and the publication of clinical results, allowing for reproducibility and comparability across studies.
• Traceability and Patient Communication: Improved clarity in packaging, labelling, and patient information ensures devices are used appropriately and patients remain well-informed about their implants.

Related Standards

EN ISO 11979-1:2026 forms the foundational vocabulary for the IOL standard series. Key related documents include:

• EN ISO 11979 (all parts): The overarching series on ophthalmic implants - intraocular lenses.
• EN ISO 11979-2: Optical properties and test methods for IOLs.
• EN ISO 11979-7: Clinical investigations of intraocular lenses for the correction of aphakia.

Integration with these and other healthcare technology vocabularies (ICS 01.040.11) and standards related to ophthalmic equipment (ICS 11.040.70) ensures comprehensive coverage and compatibility across the international medical device landscape.

---

By standardizing intraocular lens terminology, EN ISO 11979-1:2026 supports innovation, safety, and effective clinical outcomes throughout the ophthalmic industry. For stakeholders seeking to ensure compliance, interoperability, and best practices in the field of ophthalmic implants, this standard provides essential guidance.

Standards Content (Sample)

SLOVENSKI STANDARD
01-maj-2026
Nadomešča:
SIST EN ISO 11979-1:2019
Očesni vsadki (implantati) - Intraokularne leče - 1. del: Slovar (ISO 11979-1:2026)
Ophthalmic implants - Intraocular lenses - Part 1: Vocabulary (ISO 11979-1:2026)
Ophthalmische Implantate - Intraokularlinsen - Teil 1: Vokabular (ISO 11979-1:2026)
Implants ophtalmiques - Lentilles intraoculaires - Partie 1: Vocabulaire (ISO 11979-
1:2026)
Ta slovenski standard je istoveten z: EN ISO 11979-1:2026
ICS:
01.040.11 Zdravstveno varstvo Health care technology
(Slovarji) (Vocabularies)
11.040.70 Oftalmološka oprema Ophthalmic equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 11979-1
EUROPEAN STANDARD
NORME EUROPÉENNE
March 2026
EUROPÄISCHE NORM
ICS 01.040.11; 11.040.70 Supersedes EN ISO 11979-1:2018
English Version
Ophthalmic implants - Intraocular lenses - Part 1:
Vocabulary (ISO 11979-1:2026)
Implants ophtalmiques - Lentilles intraoculaires - Ophthalmische Implantate - Intraokularlinsen - Teil 1:
Partie 1: Vocabulaire (ISO 11979-1:2026) Vokabular (ISO 11979-1:2026)
This European Standard was approved by CEN on 6 March 2026.

CEN 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 CEN
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 CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 11979-1:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 11979-1:2026) has been prepared by Technical Committee ISO/TC 172 "Optics
and photonics" in collaboration with Technical Committee CEN/TC 170 “Ophthalmic optics” the
secretariat of which is held by DIN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by September 2026, and conflicting national standards
shall be withdrawn at the latest by September 2026.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 11979-1:2018.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 11979-1:2026 has been approved by CEN as EN ISO 11979-1:2026 without any
modification.
International
Standard
ISO 11979-1
Fifth edition
Ophthalmic implants — Intraocular
2026-02
lenses —
Part 1:
Vocabulary
Implants ophtalmiques — Lentilles intraoculaires —
Partie 1: Vocabulaire
Reference number
ISO 11979-1:2026(en) © ISO 2026

ISO 11979-1:2026(en)
© ISO 2026
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
ISO 11979-1:2026(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Abbreviated terms . 10
Bibliography .11
Index .12

iii
ISO 11979-1:2026(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO 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, ISO 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
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO's adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 172, Optics and photonics, Subcommittee
SC 7, Ophthalmic optics and instruments, in collaboration with the European Committee for Standardization
(CEN) Technical Committee CEN/TC 170, Ophthalmic optics, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
This fifth edition cancels and replaces the fourth edition (ISO 11979-1:2018), which has been technically
revised.
The main changes are as follows:
— definitions of non-accommodative posterior chamber “simultaneous vision” (SVIOL) lenses that include
the subtypes of MIOL (multifocal), EDF (extended depth of focus) and FVR (full visual range) IOLs have
been added;
— definitions of properties related to SVIOLs have been added.
A list of all parts in the ISO 11979 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
International Standard ISO 11979-1:2026(en)
Ophthalmic implants — Intraocular lenses —
Part 1:
Vocabulary
1 Scope
This document contains definitions of terms related to intraocular lenses as well as definitions related to
the methods used to evaluate these IOLs.
NOTE The terms are listed in the alphabetical order of the English terms.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
accelerated shelf-life study
study to establish an initial expiration dating period by using exaggerated storage conditions by increased
temperature to be validated by real time study
3.2
accommodating intraocular lens
AIOL
IOL providing focusing from far point to near point by changing the dioptric power of the eye
3.3
accommodative amplitude
difference in refractive power between the near point and the far point of the eye
3.4
addition power
difference between the far power and the near power
3.5
additional wrapping
protective packaging used in addition to the primary packaging which can be used to maintain sterility of
the intraocular lens
3.6
anterior chamber lens
IOL designed to be placed entirely in the anterior chamber of the eye

ISO 11979-1:2026(en)
3.7
aspheric intraocular lens
IOL having at least one optical surface whose curvature varies radially from the vertex to the periphery
3.8
axial displacement in compression
displacement of optic along the optical axis when the IOL is compressed to a specified diameter taking the
uncompressed state as reference
3.9
axis mark
indicator of the meridian of lowest dioptric power of a toric IOL
Note 1 to entry: See Figure 1.
3.10
back focal length
BFL
distance from the back vertex of the IOL to the focal point with collimated light incident on-axis upon the IOL
3.11
base power
dioptric power that is intended to provide an in-focus image of an object at far (infinity)
Note 1 to entry: Base power is the same as far power.
3.12
best-case subject
subject with no pre-operative ocular pathology detected at any time, e.g. no macular degeneration, and no
previous surgery for the correction of refractive errors
3.13
body
part of an IOL incorporating the optic excluding the haptics
Note 1 to entry: See Figure 1.
3.14
clear optic
diameter of concentric circle with the optical axis of an intraocular lens, containing only features of the
intraocular lens belonging to the optical design
Note 1 to entry: See Figure 1.
3.15
closed-loop intraocular lens
IOL model which contains two loops, each loop having both ends attached to the body of the optic
3.16
compression force
force exerted by the haptics of the IOL when compressed to a specified diameter

ISO 11979-1:2026(en)
Key
1 overall diameter
2 positioning hole
3 clear optic
4 body
h vault height
h sagittal distance
Figure 1 — Overall diameter, vault height, sagittal distance, clear optic, body, positioning hole and
axis mark
3.17
cumulative adverse events
total number of adverse events that have occurred at any time up to a specified post-operative time point
3.18
custom-made device
device specifically made in accordance with a duly qualified medical practitioner's written prescription,
which gives, under his/her responsibility, specific design characteristics and is intended for the sole use of a
particular patient
Note 1 to entry: Mass-produced devices, which need to be adapted to meet the specific requirements of the medical
practitioner, are not considered to be custom-made devices.
3.19
cut-off wavelength
wavelength at which spectral transmission drops below a defined level
3.20
cylindrical power
difference in dioptric power between the meridians with the highest and the lowest dioptric powers
3.21
delivery system
system, either preloaded or combined, in which the IOL is compressed and/or folded and delivered into the
eye
ISO 11979-1:2026(en)
3.22
device history record
collection of records and reports assembled in a batch package, containing or referring to the relevant
information pertaining to the manufacture and control of that batch of devices
3.23
dioptric power
reciprocal of the reduced paraxial focal length in situ, where paraxial focal length is the distance between
the back principal plane and the back paraxial focal point, and reduced paraxial focal length is the paraxial
focal length divided by the refractive index of the surrounding medium
-1
Note 1 to entry: The unit for expressing dioptric power is the reciprocal metre (m ). The special name for this unit is
“dioptre”, for which the symbol “D” is used.
Note 2 to entry: Refer to ISO 11979-2 for the test conditions.
Note 3 to entry: For certain IOL
...