ISO 10934:2025
(Main)Microscopes — Vocabulary for light microscopy
Microscopes — Vocabulary for light microscopy
This document specifies terms and definitions to be used in the field of light microscopy and advanced techniques in light microscopy.
Microscopes — Vocabulaire relatif à la microscopie optique
General Information
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Standards Content (Sample)
International
Standard
ISO 10934
Second edition
Microscopes — Vocabulary for light
2025-05
microscopy
Microscopes — Vocabulaire relatif à la microscopie optique
Reference number
© ISO 2025
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ii
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. 46
Bibliography .58
Index .59
iii
Foreword
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This document 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 10934:2020, which has been technically
revised.
The main changes are as follows:
— added new terms for light microscopy: airy beam, Bessel beam, achromatic condenser, detection path,
extinction ratio, focal volume, Gaussian beam, illumination path, spatially coherent illumination,
temporally coherent illumination, microlens, immersion objective, water dipping objective, hot pixel,
dead pixel, stuck pixel, voxel, digital zoom;
— added new terms for advanced techniques in light microscopy: averaging, sampling, sampling rate,
Nyquist sampling, oversampling, undersampling, resonant frequency scanning, multi-view fusion, light
sheet fluorescence microscopy, spectral unmixing, computational microscopy, stitching, point spread
function engineering, high content screening, high throughput screening, light field microscopy, point
detector, photodiode, photomultiplier, avalanche photodiode, area detector, linear array sensor, single-
photon avalanche diode array, sCMOS, CCD, EMCCD;
— terms amended;
— 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
International Standard ISO 10934:2025(en)
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 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 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 (3.1.105)objectives
(3.1.112)
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 or
with reflective stripes are also in use.
3.1.2
Abbe theory of image formation
explanation of the mechanism by which the microscope (3.1.105)image (3.1.80) 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 (3.1.92) 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 (3.1.80)
3.1.4.1
astigmatism
aberration (3.1.4) which causes rays in one plane containing an off-axis object (3.1.110) point and the optical
axis (3.1.113) 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 (3.1.92) or prism (3.1.125), due to dispersion (3.1.50) 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 (3.1.93) of different wavelengths is focused at different points along the
optical axis (3.1.113)
3.1.4.2.2
lateral chromatic aberration
chromatic difference of magnification
aberration (3.1.4) by which the images (3.1.80) formed by light (3.1.93) of different wavelengths, although
they may be brought to the same focus (3.1.69) in the optical axis (3.1.113), are of different sizes
3.1.4.3
coma
aberration (3.1.4) in which the image (3.1.80) of an off-axis point object (3.1.110) 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 (3.1.57.4) from a plane object field (3.1.57.5)
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.
Note 2 to entry: The quality of curvature of image field is described in ISO 19012-1. See OFN (3.1.57.6).
3.1.4.5
distortion
aberration (3.1.4) in which lateral magnification (3.1.95.8) varies with distance from the optical axis (3.1.113)
in the image field (3.1.57.4)
3.1.4.5.1
barrel distortion
negative distortion
difference in lateral magnification (3.1.95.8) between the central and peripheral areas of an image (3.1.80)
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).
3.1.4.5.2
pincushion distortion
positive distortion
difference in lateral magnification (3.1.95.8) between the central and the peripheral areas of an image
(3.1.80) 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
(3.1.129.2)light (3.1.93)
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 (3.1.110) point
on the optical axis (3.1.113), 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 (3.1.92) 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 (3.1.105)objective (3.1.112) 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.
Note 2 to entry: For more information see ISO 19012-2.
3.1.7
Airy beam
non-diffracting, self-reconstructing beam whose planar profiles perpendicular to the beam axis are
described with two-dimensional Airy functions
Note 1 to entry: Airy beams are typically created with a cubic phase mask or a spatial light modulator.
3.1.8
Airy pattern
image (3.1.80) of a primary or secondary point source (3.1.141.1) of light (3.1.93) which, due to diffraction
(3.1.44) at a circular aperture (3.1.11) of an aberration-free lens (3.1.92), takes the form of a bright disc
surrounded by a sequence of concentric dark and bright rings
3.1.8.1
Airy disc
diffraction disc
central area bounded by the first dark ring of the Airy pattern (3.1.8)
Note 1 to entry: The Airy disc contains 84 % of the energy of the Airy pattern.
3.1.8.2
Airy unit
AU
diameter of the theoretical first minimum of the Airy pattern (3.1.8) in the low numerical aperture (3.1.11.4)
approximation
λ
ref
Note 1 to entry: AU=12, 2 , where λ is the reference wavelength and NA the numerical aperture.
ref
NA
3.1.9
anisotropic
having a non-uniform spatial distribution of properties
Note 1 to entry: In polarized light microscopy, this usually refers to the preferential
...
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