ISO 8578:2012

Microscopes - Marking of objectives and eyepieces

ISO 8578:2012 specifies the format for the marking of data or symbols for optical characteristics on microscope objectives and eyepieces and the positioning of the data. It makes recommendations for the marking of additional information, particularly colour coding of rings designating the magnification of objectives and the immersion media with which they are used.

Microscopes — Marquage des objectifs et des oculaires

General Information

• Status: Published
• Publication Date: 28-May-2012
• ICS: 37.020 - Optical equipment
• Technical Committee: ISO/TC 172/SC 5 - Microscopes and endoscopes
• Drafting Committee: ISO/TC 172/SC 5 - Microscopes and endoscopes
• Current Stage: 9092 - International Standard to be revised
• Start Date: 05-Feb-2025
• Completion Date: 13-Dec-2025

Relations

• Revises: ISO 8578:1997 - Microscopes - Marking of objectives and eyepieces
• Effective Date: 28-Feb-2009

Overview

ISO 8578:2012 - Microscopes - Marking of objectives and eyepieces specifies standardized formats and placement for optical data and symbols on microscope objectives and eyepieces. The standard ensures that essential information (magnification, numerical aperture, tube length, cover-glass thickness, immersion medium, field number, chromatic/field correction, etc.) is marked clearly and consistently to enable correct use, selection and servicing of microscope optics.

Key topics and requirements

• Mandatory objective markings: Includes magnification and numerical aperture (e.g., 100/1.30), tube length or infinity symbol (e.g., 160 or ∞), cover-glass thickness (e.g., /0.17, /0 or /0.14-0.20 for correction collars), objective field number (OFN), chromatic correction (FL/APO), flatness (PLAN), phase contrast (PH), and manufacturer ID.
• Mandatory eyepiece markings: Visual magnification and field-of-view number separated by a slash (e.g., 10×/18) plus manufacturer identification.
• Recommended additional markings: Optional items such as colour-coded rings for magnification and immersion media, phase/contrast color coding, DIC, epi-illumination symbols, correction collars, long working distance (L, LD, LWD), and country of manufacture.
• Colour coding guidance: The standard recommends specific colours for magnification rings and immersion-media rings to aid quick identification; when an immersion ring is used it should be combined with a magnification ring and placed closer to the front lens.
• Arrangement and positioning: A recommended order of marking groups (columns A → B → C) to maintain consistency and readability across objectives.
• Examples and format rules: Specific formatting examples (e.g., ∞/0.17, OFN25, PH 2) are provided to guide manufacturers.

Applications and users

ISO 8578:2012 is used by:

• Microscope manufacturers for labelling objectives and eyepieces to meet market and regulatory expectations.
• Quality assurance and technical documentation teams to create consistent product markings and user manuals.
• Laboratory managers and procurement to verify compatibility (tube length, cover-glass correction, immersion medium).
• Service, calibration and repair technicians for correct identification during maintenance and replacement.
• Standards and regulatory bodies reviewing optical conformity.

Practical benefits include reduced user error, faster objective selection, improved interoperability of optical components, and clearer maintenance records.

Related standards

• ISO 8036 - Immersion liquids for light microscopy
• ISO 19012‑1 - Designation of microscope objectives - Part 1: Flatness of field / Plan
• ISO 19012‑2 - Designation of microscope objectives - Part 2: Chromatic correction

Keywords: ISO 8578:2012, microscopes, marking of objectives and eyepieces, objective markings, eyepiece markings, colour coding, numerical aperture, magnification, immersion media.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 8578
Second edition
2012-06-01
Microscopes — Marking of objectives
and eyepieces
Microscopes — Marquage des objectifs et des oculaires
Reference number
©
ISO 2012
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 ISO at the address below or ISO’s
member body in the country of the requester.
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Published in Switzerland
ii © ISO 2012 – All rights reserved

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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 8578 was prepared by Technical Committee ISO/TC 172, Optics and photonics, Subcommittee SC 5,
Microscopes and endoscopes.
This second edition cancels and replaces the first edition (ISO 8578:1997) which has been technically revised.
It also incorporates the Technical Corrigendum ISO 8578:1997/Cor. 1:2002.
Introduction
This International Standard has been prepared in order to define clearly the data relating to optical characteristics
with which microscope objectives and eyepieces have to be marked and the positioning of such marking on the
component to enable correct use of the microscope. In addition to data which have been marked, recommendations
for the marking of additional information relating to several other optical characteristics are given.
iv © ISO 2012 – All rights reserved

INTERNATIONAL STANDARD ISO 8578:2012(E)
Microscopes — Marking of objectives and eyepieces
1 Scope
This International Standard specifies the format for the marking of data or symbols for optical characteristics
on microscope objectives and eyepieces and the positioning of the data. It makes recommendations for the
marking of additional information, particularly colour coding of rings designating the magnification of objectives
and the immersion media with which they are used.
2 Normative references
The following referenced documents are indispensable for the application 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 8036, Optics and photonics — Microscopes — Immersion liquids for light microscopy
ISO 19012-1, Microscopes — Designation of microscope objectives — Part 1: Flatness of field/Plan
ISO 19012-2, Optics and photonics — Designation of microscope objectives — Part 2: Chromatic correction
3 Objectives
3.1 Mandatory markings on objectives
The markings on objectives shall be as given in Table 1.
Tube length and cover glass thickness shall be marked in this sequence and shall be separated by oblique
strokes and be in one line, e.g. ∞/0.17, 160/-, ∞/0. This marking shall be in a smaller font than markings
according to Table 3. The objective field number (OFN) shall be marked according to the following example:
OFN25
3.2 Recommended additional markings on objectives
The marking of additional data is optional. If features as listed in Table 2 are marked, they shall be marked as
given in Table 2.
3.3 Recommendation for arrangement of the marking
It is recommended that the markings in Table 3, column A should be placed above or before the markings of
column B, which in turn should be placed above or before those of column C.
4 Eyepieces
4.1 Mandatory markings on eyepieces
The markings on eyepieces shall be as specified in Table 4.
4.2 Recommended additional markings on eyepieces
The marking of additional data is optional. If features as listed in Table 5 are marked, they shall be marked as
given in Table 5.
Table 1 — Mandatory markings on objectives
Optical Example of
Feature to be marked Remarks
a
property marking
Magnification Lateral magnification of 100 Magnification and numerical aperture shall be
objectives for a finite image separated by an oblique stroke, e.g. 100/1.30.
distance.
Lateral magnification of 1
...