Getting Started With The Microscope - Phonak Lyric2 Instruction Booklet

Getting started with the microscope

Step 1 Adjusting eye distance
Important
It is not necessary to have a sharp focus during this step! Before
working with the microscope the eye distance of the oculars needs
to be adjusted to avoid shadows and to ensure a round field of
vision.
First, the oculars are set to the widest distance possible by
à
turning the dial located on the lefthand side. People who wear
glasses must push back the rubber eye-piece cushions to ensure
the correct distance is maintained between the eyes and the
ocular.
à Switch on the light and look through the eye-pieces. Slowly turn
the dial to decrease the distance between the oculars, until a
round sector is visible. There should be no shadow, overlapping
or double images in the centre. Once you are happy with this
image, there is no need to adjust the dial further.
Step 2 Focusing the microscope
Setting the focus of the microscope is only achieved by adjusting
the distance between the microscope and the object to be
examined. There is no need to change the position of the knob or
the eye-pieces in order to get a focused image.
Advice: People who must wear corrective lenses due to spherical
refractive errors when viewing distant objects may set the
corresponding dioptre number on the eye-pieces and adjust the
focus. For further information please refer to the paragraph
below: "Positioning of the microscope oculars".
Start with the microscope 20cm away from the patient's ear.
à
Slowly move the microscope forward towards the ear until the
image is focused.
à When examining the ear it is recommended to focus on the concha
first. Gradually move the microscope forward to see a focused
image of the ear canal. Work your way from the outside to the
inside, finishing with a focused view of the tympanic membrane.
Positioning of the microscope oculars
The microscope oculars allow for for manual corrections to be
made depending on the difference in vision between the two eyes.
This is to allow for binocular vision and depth of field when there
is different vision in both eyes.
à To adjust the dioptre settings, first loosen the clamp screw on
the right eye-piece. Then set the eye-piece dioptre scale to "0"
and focus on an area of reference (e.g. head-rest) with the
microscope until it appears in focus for the right eye only.
à While maintaining this microscope position, adjust the left
eye-piece dioptre scale so that both eyes see the object evenly.
Once the dioptre has been set, the clamp screw must be
retightened. If glasses or contact lenses are worn while using the
microscope, any differences between the eyes should already
have been eliminated and adjustments should not be necessary.
Advice: If more than one person is working with the microscope,
it is recommended to note the adjustment figures in order to to
make future set up quicker.
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