Filters; Apertures - Haag-Streit BM 900 Mode D'emploi

4. Rotate the control lever (45) until the light beam is at eye
level.
5. Holding the control lever (45), inclined towards yourself, move
the instrument base until the slit appears to be approximately
in focus on the cornea. This coarse setting is achieved with
the naked eye. Fine adjustments are obtained by rotating
and tilting the lever while observing the image through the
microscope (40).
6. The slit width is adjusted to the left or right by means of the
knob (44), which also adjusts the angle between the microscope
and the illumination unit.
7. The slit image is made vertical, horizontal, or given any
desired angle by means of control knob (39) (notches at 45°,
90° and 135°; stops at 0° and 180°).
8. In order to ensure the possibility of conducting a binocular
fundus examination in optical cross section without difficulty
from side angles between 3° and 10°, the shorter mirror (11)
should be installed, the illumination unit is rotated through
90° with the knurled control knob (39) and with the latch (43)
in stages of 5°, the illumination unit and the microscope are
turned to the center position (0°).
9. The magnification of the microscope in the Slit Lamp
BM 900 is altered by changing the lens with the lever (41) or
®
by exchanging the eyepieces.
10. Loosening the centering screw (42) will allow the slit image
to be moved off center for scleral illumination. Tightening
the screw will recenter the slit image in the visual field of the
microscope.
11. For general observations over a wide field the grey filter
is placed in position by means of lever (38), and the slit is
opened wide.
12. For examination of the posterior of the eye, preset lenses
or diagnostic contact lenses have to be used.
3.4

Filters (38)

46 Open aperture
47 Grey filter (10%)
48 Redfree filter
49 Empty space for accommodating an add. filter
Due to standard ISO 10939 the heat absorption filter and UV
filter are permanently mounted!
3.5 Apertures (37) operating (39)
50 Fixation star*
51 Apertures producing areas of 8, 5, 3, 2, 1 and 0.2 mm ø
52 Indication of wedge-shaped diaphragm for continuous
slit length adjustment in mm
53 Blue filter
* The target with the fixation star is particularly suitable for
examining the fixation in amblyopia.
50
1500.7200492.04090
37
38
39
40
41
42
43
44
45
46 47 48
51
© Haag-Streit AG, CH-3098 Koeniz, Switzerland
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