Filter
Top Products
2.
Mounting the
Eyepieces
For mounting, simply drop
the
eyepiece into
the
eyepiece tube.
It is
recommended
to
leave
an
eyepiece
in
place even when
it is not in use, in
order
to
prevent
the
entrance
of
dust into
the
eyepiece tube.
Or
put
on the
eyepiece
cap
in
place
of the
eyepiece removed.The
inclined eyepiece body
tube,
trinocular, bino-
cular
or
monocular,can
be rotated after loosen-
ing
the
clamp screw
(Fig.
6) for
conveni-
ence
in
viewing from
any desired direction
without
moving
the
microscope stand.
By
further releasing
the
clamp screw
the
body tube
can
be
removed
and
replaced with another type eyepiece body tube.
3.
IVIounting the
Condenser
To
mount
the
condenser, unlock
the
lock screw,
and
insert
the
condenser
beneath the condenser
holder
as far as it
will
go. Then, tighten
the
lock screw.
In
this
case locate
the
dia-
phragm eccentering
lever
and its
screw
at
a proper place
so as
to
facilitate their
manipulation
with
one
hand
(Fig. 7). The
correct distance
to re-
tain
immersion
oil be-
tween
the
lower sur-
face
of the
slide
and
the
top of
condenser
is secured when
the
condenser
is
raised
to the
upper
limit
by
turning
the
condenser focusing
knob.
-11—
ILLUMINATION
Resolution
and
contrast
of
image
are
greatly affected
by the
method
of
illumination.
1.
Condenser
Iris Diaphragm and
Images
Stop down
the
condenser iris diaphragm
and
slide
it in the
radial direc-
tion
from center
to
edge.
The
farther
the
iris diaphragm
is
off-centered,
the
higher becomes
the
contrast
and
resolution, which distinguish details
of
object
by
increased
and
unsymmetrical shadow
at the
boundary
of
object
(Fig.
8, a, b).
(a)
Central illumination (b) Oblique illumination (c) Dark field illumination
When
the
iris diaphragm
is
positioned
so as to let the
light bundle enter into
the
object
at an
angle
o'f
incidence
the
same
as the
aperture angle
of the
objective
the
resolution reaches maximum
and
twice
as
much
as the
resolution
by
central illumination.
If
the
diaphragm
is
further eccentered
to
such
an
extent
as not to
introduce
the
light bundle directly into
the
objective, dark field
illumi-
nation will
be
obtained.
If the
iris diaphragm
is
widely opened, images
by various angle illuminations
are
integrated.
An
illumination angle
not
favorable
for the
object
may be
included.
In
the
central illumination
the
maximum resolution
is
obtained when
the
opening
of the
iris diaphragm just corresponds
to the
aperture angle
of
the
objective.
In
this case
excessive
outer
rays
to be
used
as
dark
field
illumination
are cut off and
flare
is
minimized.
If the
opening
is
made
smaller,
the
contrast
is
enhanced, though
the
resolution
is
lowered.
But
if
the
iris diaphragm
is
large enough
to
cover
60-70%
of the
objective
aperture,
the
decrease
of
resolution will
not be
remarkable.
If
the
diaphragm
is
stopped down
to
minimum
for
admitting only
very
—12—