Illumination And Contrasting Techniques; Setting Of Transmitted-Light Brightfield For Köhler Illumination - Zeiss Axiovert 200 Operating Manual

Carl Zeiss
3.3

Illumination and contrasting techniques

3.3.1 Setting of transmitted-light brightfield for KÖHLER illumination
3.3.1.1 General principle
Transmitted-light brightfield microscopy is the most usual of all the optical techniques, since it allows the
easy and fast viewing of high-contrast or stained specimens (e.g. blood smears).
In addition to so-called direct beam bundles, indirect bundles which are diffracted and scattered at the
specimen details, are of major importance for an image as true to the object as possible. The greater the
portion of the indirect bundles (aperture), the more the microscope image will be true to the object,
according to ABBE.
To make use of the entire optical performance of the microscope and the objective in particular, the
condenser, the luminous-field diaphragm and the aperture diaphragm should be set in accordance with
the rules of KÖHLER illumination. These basic rules of microscope setting are described in detail in the
following section 3.3.1.3, "Transmitted-light brightfield setting according to KÖHLER on the Axiovert
200 (manual)".
3.3.1.2 Transmitted-light brightfield configuration of the Axiovert 200 manual
Each manual Axiovert 200 microscope can be configured to permit the transmitted-light brightfield
technique.
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OPERATION

Illumination and contrasting techniques

Axiovert 200
B 40-080 e 03/01