Page 113 - The Veterinary Laboratory and Field Manual 3rd Edition

82 Willy Schauwers

Figure 2.47 Parts of the microscope, Leica DM4. Photo: Manuela Jacobsen, Leica Biosystems, Wetzlar,
courtesy of Leica Microsystems CMS GmbH, Wetzlar, Germany.

objEctIvES the eyepiece (usually 10×) by the magnification
The underside of the arm of the microscope con- listed on the objective being used. For example,
tains a revolving ‘turret’ to which the objective an object viewed using a 10× ocular and high
lenses are attached. Most microscopes have four power (40×) objective would be magnified 400
objective or magnifying lenses: times. An object viewed with a 10× ocular and
the oil immersion objective (100×) would be
• the lower power objective, which magnifies magnified 1000 times.
10× For the ‘oil immersion objective’ (100×) it
• the high-power objective, which magnifies is necessary to use special microscope oil. It is
40× important not to get this oil on the other lenses
• the oil immersion objective, which magnifies as it will distort the image.
100×
• additional objectives (4×, 20×) can also be condEnSEr and dIaPHraGM
purchased. The arm of the microscope connects the objec-
tives and eyepiece(s) to the microscope base,
Each objective is marked with colour-coded which supports the microscope. The base also
bands and the power of magnification. contains the light source. The light source beam
To determine the degree of magnification in has a movable condenser and iris diaphragm
use, multiply the magnification mentioned on located above it. The condenser focuses or

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