Microscopia

Microscopy in everyday use
Small causes – major repercussions
_ Relaxed viewing is important
If you are a “beginner” in microscopy, you may tend to tense
up when viewing. You think you have to set your eyes for near
vision because, after all, you want to view something small.
This is not the correct attitude in microscopy and may cause
you strain in the long run – and you do not even know thecause. There is an easy remedy: First, look into the distance
with your eyes relaxed and then into the eyepieces – without
changing the setting of your eyes. Only then should you set
the interpupillary distance of the eyepieces via the folding
bridge until you see only one circle instead of two. Remember
to consciously use both your eyes for viewing.
_ Keep your distance
Microscope eyepieces fromCarl Zeiss have usually been
designed for eyeglass wearers. Therefore, the exit pupil of the
eyepiece is at a considerable distance from the eyepiece. Users
who do not wear eyeglasses should also keep this distance to
permit the entire light from the microscope to find its way to
the iris of the eye. If you slowly move your head to and fro in
front of the eyepieces, you will soon find the optimum,relaxed
posture allowing you to see the entire circle of the field of
view.
If you do not wear eyeglasses, the rubber cups on the eyepieces
will be useful to you. They not only protect the eye from
ambient light, but also help to keep the correct distance between
the eye and the eyepiece.
_ Exclusively for eyeglass wearers: a little test
Eyeglass wearers requiring simple lenses with a sphericalpower can use the microscope with or without their glasses,
provided that the diopter setting of the (“foc”) eyepiece is sufficient.
However, if you require lenses with a toric power, i.e.
lenses which diffract light differently in the horizontal and vertical
– you had better wear your glasses for microscopy, since
your eye then has unsymmetrical aberrations which cannot be
compensated by thediopter setting alone. This is how you test
your glasses (see the pictures on the left): view a simple geometric
figure – a circle or a square – through the glasses you
have removed from your eyes. First you hold the glasses horizontally,
then vertically. If the figure appears compressed or
expanded by this rotation about 90°, you will know that you
are wearing lenses with a toric or anothernon-spherical
power.
12.1
12.2
12. Avoid the use of force
The sturdy design of our microscopes will even excuse
incorrect treatment. However, the front tip of the objective
with the sensitive front lens is one particularly critical area.
The following precautions have been taken to protect the
objective.
– The entire front optics of objectives with a high magnification
are contained in a resilient mount.When touched, this
mount “backs away” a little. However, the distance available
for this movement is only small. Therefore, please make sure
that you do not move the stage too much upwards during
focusing. In such cases, the sample will press against the
objective tip, and once the front lens cannot retreat any further,
the outcome may be an expensive breakage of glass.
– Immersion objectives have anadditional protection facility to
the one described above: they can be locked in the topmost
position by carefully turning the front group. The objectives
can thus be “parked” at a safe distance. On the other hand,
however, the escape route described above is then no longer
available.
Should you not be satisfied with the function of your immersion objective,
please check whether it is in the“parked position”. This is the case if, after a
change of objectives, the focus is far away from the one set before.
_ Protect your investment: the dust cover
Microscopes are used for an average of 15 years or longer.
Just like rust attacks the car, the problem in microscopes is
dust which is present almost everywhere.
Therefore: please switch off the illuminator(s) and put the
supplied dust cover...