ISO 10934:2020

INTERNATIONAL ISO
STANDARD 10934
First edition
2020-08
Microscopes — Vocabulary for light
microscopy
Microscopes — Vocabulaire relatif à la microscopie optique
Reference number
©
ISO 2020
© ISO 2020
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ii © ISO 2020 – All rights reserved

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 Terms and definitions relating to light microscopy . 1
3.2 Terms and definitions relating to advanced techniques in light microscopy .44
Bibliography .54
Index .55
Foreword
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is o/ f or ewor d . ht m l .
This document was prepared by Technical Committee ISO/TC 172, Optics and photonics, Subcommittee
SC 5, Microscopes and endoscopes.
This first edition cancels and replaces ISO 10934-1:2002 and ISO 10934-2:2007, which have been
combined and technically revised.
The main changes compared to the previous edition are as follows:
— update of the title;
— added new terms for light microscopy: focal length of normal tube lens, objective field number,
pixel, pixel size, Airy unit, excitation wavelength, excitation wavelength band, detection wavelength
band, OSTD added as new terms;
— added new terms for advanced techniques in light microscopy: coherent anti-stokes Raman
scattering microscopy, stimulated Raman scattering microscopy, structured illumination
microscopy, super-resolution microscopy, localization microscopy, stimulated emission depletion
microscopy, super-resolution structured illumination microscopy, light sheet microscopy, digital
holographic microscopy, optical coherence microscopy;
— terms amended: diffraction limit of resolving power, resolution;
— editorially revised.
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 © ISO 2020 – All rights reserved

INTERNATIONAL STANDARD ISO 10934:2020(E)
Microscopes — Vocabulary for light microscopy
1 Scope
This document specifies terms and definitions to be used in the field of light microscopy and advanced
techniques in light microscopy.
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 terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1 Terms and definitions relating to light microscopy
3.1.1
Abbe test plate
device for testing the chromatic (3.1.4.2) and spherical aberration (3.1.4.7) of microscope (3.1.99)
objectives (3.1.106)
Note 1 to entry: When testing for spherical aberration, the cover glass thickness for which the objective is best
corrected is also found. The test plate consists of a slide on which is deposited an opaque metal layer in the
form of parallel strips arranged in groups of different width. The edges of these strips are irregularly serrated to
allow the aberrations to be judged more easily. In its original and most common form, the slide is covered with a
wedge-shaped cover glass, the increasing thickness of which is marked on the slide. Additional versions without
the cover glass and/or with reflective stripes are also in use.
3.1.2
Abbe theory of image formation
explanation of the mechanism by which the microscope (3.1.99) image (3.1.75) is formed
Note 1 to entry: It assumes coherent illumination and is based on a three-step process involving diffraction.
a) First step: the object diffracts light coming from the source.
b) Second step: the objective collects some of the diffracted beams and focuses them, according to the laws of
geometrical optics, in the back focal plane of the objective to form the primary diffraction pattern of the object.
c) Third step: the diffracted beams continue on their way and are reunited; the result of their interference is
called the primary image of the microscope.
This explains the necessity for the maximum number of rays diffracted by the object to be collected by the
objective, so that they may contribute to the image. Fine detail will not be resolved if the rays it diffracts are not
allowed to contribute to the image.
3.1.3
aberration
deviation from perfect imaging by an optical system, caused by the
properties of the material of the lenses (3.1.87) or by the geometric forms of the refracting or reflecting
surfaces
3.1.4
aberration
failure of an optical system to produce a perfect image (3.1.75)
3.1.4.1
astigmatism
aberration (3.1.4) which causes rays in one plane containing an off-axis object (3.1.104) point and the
optical axis (3.1.107) to focus at a different distance from those in the plane at right angles to it
3.1.4.2
chromatic aberration
aberration (3.1.4) of a lens (3.1.87) or prism (3.1.119), due to dispersion (3.1.47) by the material from
which it is made
Note 1 to entry: This defect may be corrected by using a combination of lenses made from glasses or other
materials of different dispersion.
3.1.4.2.1
axial chromatic aberration
aberration (3.1.4) by which light (3.1.88) of different wavelengths is focused at different points along
the optical axis (3.1.107)
3.1.4.2.2
lateral chromatic aberration
chromatic difference of magnification
aberration (3.1.4) by which the images (3.1.75) formed by light (3.1.88) of different wavelengths, although
they may be brought to the same focus (3.1.65) in the optical axis (3.1.107), are of different sizes
3.1.4.3
coma
aberration (3.1.4) in which the image (3.1.75) of an off-axis point object (3.1.104) is deformed so that the
image is shaped like a comet
3.1.4.4
curvature of image field
aberration (3.1.4) resulting in a curved image field (3.1.54.4) from a plane object field (3.1.54.5)
Note 1 to entry: Curvature of the image field is particularly obvious with objectives of high magnification and
large numerical aperture, which have a restricted depth of field. It may largely be eliminated by additional
correction.
3.1.4.5
distortion
aberration (3.1.4) in which lateral magnification (3.1.90.8) varies with distance from the optical axis
(3.1.107) in the image field (3.1.54.4)
3.1.4.5.1
barrel distortion
negative distortion
difference in lateral magnification (3.1.90.8) between the central and peripheral areas of an image
(3.1.75) such that the lateral magnification is less at the periphery
EXAMPLE A square object in the centre of the field thus appears barrel shaped (i.e. with convex sides).
2 © ISO 2020 – All rights reserved

3.1.4.5.2
pincushion distortion
positive distortion
difference in lateral magnification (3.1.90.8) between the central and the peripheral areas of an image
(3.1.75) such that the lateral magnification is greater towards the periphery
EXAMPLE A square object in the centre of the field thus appears pincushion shaped (i.e. with concave sides).
3.1.4.6
monochromatic aberrations
collective term for all aberrations (3.1.4) outside the Gaussian space which appear for monochromatic
(3.1.123.2) light (3.1.88)
Note 1 to entry: The monochromatic aberrations are: spherical aberration, coma, astigmatism, curvature of
image field and distortion.
3.1.4.7
spherical aberration
aberration (3.1.4) resulting from the spherical form of the wavefront arising from an object (3.1.104)
point on the optical axis (3.1.107), on its emergence from the optical system
Note 1 to entry: As a consequence, the rays emanating from an object point on the optical axis at different angles
to the axis, or rays entering the lens parallel to the optical axis but at differing distances from it, intersect the
optical axis in the image space before (undercorrection) or behind (overcorrection) the ideal image point formed
by the paraxial rays.
3.1.5
achromat
lens (3.1.87) in which the axial chromatic aberration (3.1.4.2.1) is corrected for two
wavelengths
EXAMPLE Usually the correction is made for a wavelength below 500 nm and for a wavelength above 600 nm.
3.1.6
achromat
microscope (3.1.99) objective (3.1.106) in which chromatic aberration (3.1.4.2) is
corrected for two wavelengths and spherical aberration (3.1.4.7) and other aperture-dependent defects
are minimized for one other wavelength which is usually about 550 nm
EXAMPLE Usually the correction is made for a wavelength below 500 nm and for a wavelength above 600 nm.
Note 1 to entry: This term does not imply any degree of correction for curvature of image field; coma and
astigmatism are minimized for wavelengths within the achromatic range.
3.1.7
Airy pattern
image (3.1.75) of a primary or secondary point source (3.1.135.1) of light (3.1.88) which, due to diffraction
(3.1.41) at a circular aperture (3.1.10) of an aberration-free lens (3.1.87), takes the form of a bright disc
surrounded by a sequence of concentric dark and bright rings
3.1.7.1
Airy disc
diffraction disc
central area bounded by the first dark ring of the Airy pattern (3.1.7)
Note 1 to entry: The Airy disc contains 84 % of the energy of the Airy pattern.
3.1.7.2
Airy unit
AU
diameter of the theoretical first minimum of the Airy pattern (3.1.7) in the low numerical aperture
(3.1.10.4) approximation
λ
ref
Note 1 to entry: AU=12, 2
NA
Where λ is the reference wavelength and NA the numerical aperture.
ref
3.1.8
anisotropic
having a non-uniform spatial distribution of properties
Note 1 to entry: In polarized light microscopy, this usually refers to the preferential orientation of optical
properties with respect to the vibration plane of the polarized light.
3.1.9
apertometer
device for measuring the numerical aperture (3.1.10.4) of microscope (3.1.99) objectives (3.1.106)
3.1.10
aperture
area of a lens (3.1.87) which is available for the passage of light (3.1.88)
Note 1 to entry: In microscopy, it is usually expressed as the numerical aperture.
3.1.10.1
angular aperture
maximum plane angle subtended by a lens (3.1.87) at the centre of an object field
(3.1.54.5) or image field (3.1.54.4) by two opposite marginal rays when the lens is used in its correct
working position
Note 1 to entry: The term may be qualified by the side of the lens to which it refers (e.g. object side, illumination
side, image side).
3.1.10.2
condenser aperture
illuminating aperture
aperture (3.1.10) of the illuminating system
...