ISO/TR 21477:2017

Optics and photonics — Preparation of drawings for optical elements and systems — Surface imperfection specification and measurement systems

ISO/TR 21477:2017 intends to guide the user to understand the origins, meanings and differences between the two systems of specifying and evaluating surface imperfections in ISO 10110-7 and ISO 14997, specifically the dimensional method and the visibility method, and to provide information on how to use them. Tables are provided to show specifications of roughly equivalent yield loss for imperfections in the two systems.

Optique et photonique — Préparation des plans pour les éléments et systèmes optiques — Spécification des imperfections de surface et systèmes de mesure

General Information

• Status: Published
• Publication Date: 15-Aug-2017
• ICS: 37.020 - Optical equipment
• Technical Committee: ISO/TC 172/SC 1 - Fundamental standards
• Drafting Committee: ISO/TC 172/SC 1/WG 1 - General optical test methods
• Current Stage: 6060 - International Standard published
• Start Date: 16-Aug-2017
• Completion Date: 14-Feb-2026

Overview

ISO/TR 21477:2017 focuses on the preparation of technical drawings for optical elements and systems, emphasizing the specification and measurement of surface imperfections. Developed by the International Organization for Standardization (ISO), this technical report provides essential guidance for understanding and applying two distinct systems for defining and inspecting surface flaws-those outlined in ISO 10110-7 and ISO 14997. By clarifying the origins, definitions, and critical differences between the dimensional and visibility methods, ISO/TR 21477:2017 assists optics professionals in choosing and correctly implementing the appropriate system for both manufacturing and quality assurance.

Key Topics

• Dimensional and Visibility Methods: The standard details two primary approaches for specifying surface imperfections:

  • Dimensional Method: Based on the measurement of the size or area of imperfections, suitable for performance-focused applications where flaws can impact optical function.
  • Visibility Method: Relies on the visual detectability or appearance of imperfections, often used for cosmetic assessment.

• Comparative Analysis: ISO/TR 21477:2017 explains that these two systems are fundamentally different, with unique acceptance criteria and measurement principles. It also offers guidelines on equating specifications to achieve similar yield losses across large production batches.

• Measurement Systems: The document outlines various evaluation techniques, including direct measurement using artifacts for the dimensional system and visual comparison against brightness standards for the visibility system.

• Historical Context: The report provides background on the evolution of both systems, tracing the dimensional method to German DIN standards and the visibility method to US military specifications.

Applications

ISO/TR 21477:2017 is widely applicable in the optics and photonics industries, including the manufacturing and inspection of high-precision lenses, optical components, and assemblies. Practical uses include:

• Technical Drawing Preparation: Ensuring that optical drawings clearly specify surface quality standards using either the dimensional or visibility method, in compliance with international norms.
• Quality Control: Selecting the most relevant inspection and measurement techniques for surface imperfections, depending on whether functionality or cosmetic appearance is the driving concern.
• Supplier and Customer Communication: Helping optical designers, manufacturers, and clients interpret and harmonize complex surface quality specifications, reducing the risk of miscommunication.
• Process Optimization: Enabling process engineers to balance production costs and component yields by selecting appropriate tolerances that align with performance or cosmetic requirements.

Related Standards

• ISO 10110-7: Provides the drawing notation and details for specifying permissible surface imperfections in optical elements and systems, supporting both dimensional and visibility assessment methods.
• ISO 14997: Defines the test methods for evaluating surface imperfections according to the specifications outlined in ISO 10110-7.
• DIN 3140-7 (withdrawn): Historical German standard that influenced the development of the dimensional system for surface defects.
• MIL-PRF-13830B: US military standard serving as the basis for the visibility (scratch and dig) method, widely recognized within the industry.

Conclusion

By delineating the differences and appropriate applications of the dimensional and visibility systems, ISO/TR 21477:2017 serves as a critical reference for professionals seeking to ensure accurate, reliable, and consistent specification and measurement of surface imperfections in optical drawings. Adhering to this guidance helps manufacturers, designers, and end-users improve communication, quality, and performance in optics and photonics projects.

Keywords: surface imperfection specification, optical elements, ISO 10110-7, ISO 14997, dimensional method, visibility method, scratch and dig, optics standard, drawing preparation, photonics quality.

Standards Content (Sample)

TECHNICAL ISO/TR
REPORT 21477
First edition
2017-08
Optics and photonics — Preparation
of drawings for optical elements
and systems — Surface imperfection
specification and measurement
systems
Optique et photonique — Préparation des plans pour les éléments
et systèmes optiques — Spécification des imperfections de surface et
systèmes de mesure
Reference number
©
ISO 2017
© ISO 2017, Published in Switzerland
All rights reserved. Unless otherwise specified, 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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. [phone]
Fax [phone]
[e-mail]
www.iso.org
ii © ISO 2017 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General discussion of surface imperfection specification and measurement systems .1
5 Dimensional system of surface imperfection specifications . 2
5.1 General . 2
5.2 Origin of the dimensional system . 2
5.3 Dimensional comparison standard . 2
6 Visibility system of surface imperfection specifications . 2
6.1 General . 2
6.2 Origin of the visibility system . 3
6.3 Brightness comparison standard . 3
7 Comparison of visibility and dimensional specifications . 3
Bibliography . 5
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 documents 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).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on 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 the following
URL: w w w . i s o .org/ iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 172, Optics and photonics, Subcommittee
SC 1, Fundamental standards.
iv © ISO 2017 – All rights reserved

Introduction
ISO 10110-7 provides a notation for the indication of the level of acceptability of surface imperfections
of optical elements and optical assemblies. It provides two systems of drawing notations for permissible
imperfections: one based on area and size of imperfections and the other based on the visibility or
appearance of imperfections.
ISO 14997 provides test methods for these two systems of drawing notation.
These two systems of specification and verification are totally different, with different accumulation
and acceptance rules. As a result, a user who is only familiar with one of the systems can become
confused when needing to interpret specifications in the other system. There is no way to translate
a specification in one system into a specification in the other system because their criteria for
acceptability are not interchangeable. The size or area of an imperfection is not correlated with its
visibility or brightness.
It is, however, possible to provide a specification in each system which results in practically the same
yield loss for large numbers of optical components.
TECHNICAL REPORT ISO/TR 21477:2017(E)
Optics and photonics — Preparation of drawings for
optical elements and systems — Surface imperfection
specification and measurement systems
1 Scope
This document intends to guide the user to understand the origins, meanings and differences between
the two systems of specifying and evaluating surface imperfections in ISO 10110-7 and ISO 14997,
specifically the dimensional method and the visibility method, and to provide information on how to
use them. Tables are provided to show specifications of roughly equivalent yield loss for imperfections
in the two systems.
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.
ISO 10110-7, Optics and photonics — Preparation of drawings for optical elements and systems — Part 7:
Surface imperfections
ISO 14997, Optics and photonics — Test methods for surface imperfections of optical elements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 10110-7 and ISO 14997 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
4 General discussion of surface imperfection specification and measurement
systems
ISO 10110-7 specifies the indication of the level of acceptability of surface imperfections within the
test region of individual optical elements and optical assemblies. These include localized surface
imperfections, edge chips and long scratches. It provides two systems of drawing notations for permissible
imperfections: one based on area and size of imperfections, referred to as the dimensional method, and
the other based on the visibility or appearance of imperfections, referred to as the visibility method.
ISO 14997 provides test methods for these two systems of drawing notation. For imperfections
specified using the dimensional method, three test methods are described. The first is visual evaluation
of the surface without any comparison standard (IV ). The second is a dimensional assessment of a
D
surface imperfection when compared with a dimensional comparison standard comprised of a series
of artefacts of known size (IS ). The third is the dimensional measurement of a surface imperfection
D
using magnification and either a dimensional comparison standard or a reticle or ruler (IM ).
D
For imperfections specified using the visibility method, two inspection methods are described.
The first is visual evaluation of the surface without any comparison standard (IV
...

TECHNICAL ISO/TR
REPORT 21477
First edition
2017-08
Optics and photonics — Preparation
of drawings for optical elements
and systems — Surface imperfection
specification and measurement
systems
Optique et photonique — Préparation des plans pour les éléments
et systèmes optiques — Spécification des imperfections de surface et
systèmes de mesure
Reference number
©
ISO 2017
© ISO 2017, Published in Switzerland
All rights reserved. Unless otherwise specified, 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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. [phone]
Fax [phone]
[e-mail]
www.iso.org
ii © ISO 2017 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General discussion of surface imperfection specification and measurement systems .1
5 Dimensional system of surface imperfection specifications . 2
5.1 General . 2
5.2 Origin of the dimensional system . 2
5.3 Dimensional comparison standard . 2
6 Visibility system of surface imperfection specifications . 2
6.1 General . 2
6.2 Origin of the visibility system . 3
6.3 Brightness comparison standard . 3
7 Comparison of visibility and dimensional specifications . 3
Bibliography . 5
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 documents 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).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on 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 the following
URL: w w w . i s o .org/ iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 172, Optics and photonics, Subcommittee
SC 1, Fundamental standards.
iv © ISO 2017 – All rights reserved

Introduction
ISO 10110-7 provides a notation for the indication of the level of acceptability of surface imperfections
of optical elements and optical assemblies. It provides two systems of drawing notations for permissible
imperfections: one based on area and size of imperfections and the other based on the visibility or
appearance of imperfections.
ISO 14997 provides test methods for these two systems of drawing notation.
These two systems of specification and verification are totally different, with different accumulation
and acceptance rules. As a result, a user who is only familiar with one of the systems can become
confused when needing to interpret specifications in the other system. There is no way to translate
a specification in one system into a specification in the other system because their criteria for
acceptability are not interchangeable. The size or area of an imperfection is not correlated with its
visibility or brightness.
It is, however, possible to provide a specification in each system which results in practically the same
yield loss for large numbers of optical components.
TECHNICAL REPORT ISO/TR 21477:2017(E)
Optics and photonics — Preparation of drawings for
optical elements and systems — Surface imperfection
specification and measurement systems
1 Scope
This document intends to guide the user to understand the origins, meanings and differences between
the two systems of specifying and evaluating surface imperfections in ISO 10110-7 and ISO 14997,
specifically the dimensional method and the visibility method, and to provide information on how to
use them. Tables are provided to show specifications of roughly equivalent yield loss for imperfections
in the two systems.
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.
ISO 10110-7, Optics and photonics — Preparation of drawings for optical elements and systems — Part 7:
Surface imperfections
ISO 14997, Optics and photonics — Test methods for surface imperfections of optical elements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 10110-7 and ISO 14997 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
4 General discussion of surface imperfection specification and measurement
systems
ISO 10110-7 specifies the indication of the level of acceptability of surface imperfections within the
test region of individual optical elements and optical assemblies. These include localized surface
imperfections, edge chips and long scratches. It provides two systems of drawing notations for permissible
imperfections: one based on area and size of imperfections, referred to as the dimensional method, and
the other based on the visibility or appearance of imperfections, referred to as the visibility method.
ISO 14997 provides test methods for these two systems of drawing notation. For imperfections
specified using the dimensional method, three test methods are described. The first is visual evaluation
of the surface without any comparison standard (IV ). The second is a dimensional assessment of a
D
surface imperfection when compared with a dimensional comparison standard comprised of a series
of artefacts of known size (IS ). The third is the dimensional measurement of a surface imperfection
D
using magnification and either a dimensional comparison standard or a reticle or ruler (IM ).
D
For imperfections specified using the visibility method, two inspection methods are described.
The first is visual evaluation of the surface without any comparison standard (IV
...