3 Product and Functional Description | 3.3 Light Manager Function
ZEISS
3.3 Light Manager Function
The Light Manager (LM) function saves the ratios of the set light intensities between different
combinations of objective and reflector turret positions for a given light source.
When changing the light intensity of one objective/reflector combination, the light intensities of
other combinations will also change according to the set ratios.
This ensures that users don't need to repeatedly set up light intensities for each objective/reflector
combination when switching between samples which require different illumination intensity.
After switching on the microscope, the previous setting of the Light Manager will be restored.
3.4 Microscopy and Contrast Methods
3.4.1 Transmitted Light Brightfield Microscopy Using the KÖHLER Method
Transmitted light brightfield microscopy is the most common of all optical microscopy methods,
since it can be used to quickly and easily examine high-contrast or stained samples (e.g. blood
smears).
In order to obtain an image as close as possible to the object, not only the so-called direct beam
bundles but also the indirect ones, i.e. the beam bundles diffracted and scattered at the prepara-
tion details, are of essential importance. According to ABBE, the larger the indirect beam compo-
nents are, the more true to the object the microscopic image is.
The best performance of the microscope, and especially its objective, is achieved when the con-
denser, field diaphragm and aperture diaphragm are adjusted in accordance with the KÖHLER illu-
mination principles.
3.4.2 Transmitted Light Darkfield Microscopy Using the KÖHLER Method
In the transmitted light darkfield microscopy you basically illuminate the sample with an illumina-
tion aperture which is higher than the one of the objective you are using.
In darkfield microscopy, only the diffracted and scattered light portions which are important for
the imaging procedure get into the objective, whereas the indirect unaffected light beams are di-
rected past the objective. Thus a resolution of fine structures can be achieved which is below the
resolution capacity of a light microscope. The fine structures now appear bright and incandescent
on a dark background.
Darkfield samples need to be kept impeccably clean, more so than samples for any other method.
A fingerprint, dust or any dirt particle can have a negative effect, as they brighten the background
and reduce the contrast of the object image.
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Instruction Manual ZEISS Axioscope 5, Axioscope 5/7 MAT | en-US | Rev. 13 | 430035-7344-001
