Riester ri-former Instructions Manual page 63

3. Apertures
The following apertures can be selected with the aperture hand-
wheel:
L1 ophthalmoscope
Semi-circle, small/medium/large circular aperture, fixation star,
slit and red-free filter.
L2 ophthalmoscope
Semi-circle, small/medium/large circular aperture, fixation star
and slit.
L3 ophthalmoscope
Semi-circle, small/medium/large circular aperture, fixation star,
slit and grid.
Aperture
Small circle:
Medium circle:
Semi-circle:
Large circle:
Karo:
Light slit:
Fixation star:
4 Filters
Using the filter wheel, the following filters can be switched for
each aperture:
L1 ophthalmoscope
The L1 instrument head is supplied without a filter wheel.
(the red filter is contained in the aperture wheel)
L2 ophthalmoscope
Red-free filter, blue filter and polarisation filter.
L3 ophthalmoscope
Red-free filter, blue filter and polarisation filter.
Filter
Red-free filter:
Polarisation filter:
Blue filter:
For L2 + L3, every filter can be switched to every aperture.
function
to reduce reflection for small
pupils
for normal examination results
for topographic determination
of retina changes
to determine differences in level
to ascertain central or
eccentric fixation
function
contrast enhancing to assess
fine vascular changes, e.g. retinal
bleeding
for precise assessment of tissue
colours and to avoid retinal
reflections
for improved recognition of
vascular abnormalities
or bleeding, for fluorescence
ophthalmology
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