VWR Visiscope 400 Serie Manual De Instrucciones página 11

ILLUMINATION UNIT
Using color filters
Selecting the appropriate color filters accord-
ing your need. (Fig.24)
You can stack a group of color filters in the fil-
ter holder, if you ensure that they are level and
that the whole thickness is less than 11mm.
Using the aperture diaphragm
When in brightfield observation, the aperture
diaphragm controls the numerical aperture of
the illumination system. When the numerical
aperture of the objective and the aperture of
the illumination system match, the highest res-
olution is achieved.
The aperture can be changed by moving the
aperture adjustment lever. ① is the image of
the aperture diaphragm, ② is the edge of the
objective).
Generally, when observing a fully chromatic
specimen, you need to set the size of the con-
denser to 70-80% of the aperture of the objec-
tive. When observing unstained samples (e.g.
bacteria), start from 70% and slowly turn the
aperture diaphragm lever clockwise. (Fig.25)
PHASE CONTRAST
Phase contrast slider
Adjustable phase slider.
● The light ring is pre-centered when the
microscope leaves the factory. It should
therefore need no further adjustment. If a
recentering is needed, it can be performed
via the two side bolts.
● The 4X/10X light ring ① must be used with
4X and 10X phase contrast objectives,
the 20x/40x light ring ② with the 20x and
40x and the opening ③ is used for bright
field. (Fig.26)
Installing the phase contrast slider
1. Insert the slider into the illumination
system, printed face up.
2. Pull the slider into the desired position, to
the click stop.
3. When in phase contrast observation, keep
the aperture diaphragm adjustment lever
on the "O" (open) position. (Fig.27)
①
②
COLOR
FILTER
Green Single contrast color filter used for phase
contrast microscopy
① ②
11
Fig.24
70-80%
70-
80%
30-20%
30-
20%
Fig.25
USE
③
Fig.26
Fig.27