Aperture Diaphragm; Using Color Filters; Phase Contrast - Optika Italy IM-3 Serie Manual De Instrucciones

9.9

Aperture diaphragm

The Numerical Aperture (N.A.) value of the aperture
diaphragm affects the image contrast. Increasing or
reducing this value one can vary resolution, contrast
and depth of focus of the image.
With low contrast specimens move the Aperture
Diaphragm lever (AS) ① to set the numerical aperture
to about 70%-80% of the objective's N.A. (Fig. 31)
If necessary, remove one eyepiece and, looking into
empty sleeve, adjust the condenser's ring in order to
obtain an image like the one in fig. 32.
9.10 Using color filters
Selecting the appropriate color filter according your
need. (Fig. 33)
FILTER
Green Single contrast color filter used for
phase contrast microscopy

9.11 Phase contrast

Installing the phase contrast slider
1. Insert the slider into the illumination system,
printed face up. (Fig. 34)
2. Pull the slider into the desired position, until it ar-
rives to the click stop.
3. When in phase contrast observation, keep the
aperture diaphragm adjustment lever ① on the
"O" (open) position. (Fig. 31)
USE
Page 20
IMAGE OF
APERTURE
DIAPHRAGM
FIELD OF VIEW
①
Fig. 31
70-80%
30-20%
Fig. 32
Fig. 33
Fig. 34