91
Caution:
Caution with Hg and Xe lamp :
Be careful not to project the reflection on the
electrodes for long, as there is a risk of ex-
plosion if they overheat. The two electrodes
can just be seen in the extension of the
symmetry plane of the discharge arc.
Replace spent burners in good time and
dispose of in an environment-friendly way.
Do not open the lamphousing until the lamp
has cooled down and you have disconnected
it from the mains. Wear protective clothing
(gloves and mask) when using Xe lamps. Hg
lamps take a few minutes to reach their full
intensity; they do not ignite when hot.
The adjustment principle is similar for all light
sources:
Move the reflection of the lamp filament or dis-
charge arc to the side or completely out of the
light path (62a) by turning the adjustment
screws on the back of the lamphousing (61.3 and
61.5). Focus the direct image of the filament or
discharge (61.6) and adjust as follows (61.1, 61.2
and 61.6):
Halogen lamp : just below or above the imaginary
line through the centre of the brighter circle
(62b).
First focus the reflection (61.4) and then move it
symmetrical to the direct image inside the
brighter circle (62c), or superimpose it on top of
the direct image.
Mercury- (Hg) and xenon lamp (Xe)
Move the direct image (62a) to the centre of the
brighter circle with the horizontal (61.2) and
vertical (61.1) adjustment of the holder. Focus the
reflection (61.4) and adjust the mirror until the
reflection coincides with the direct image (62c).
Fig. 61
Lamphousing 106 z
1
Vertical adjustment of lamp,
2
Horizontal adjustment of
lamp,
3, 5
Vertical and horizontal adjustment of reflection,
4
Mirror focusing,
6
Collector (focusing of lamp image),
7
Aperture for switch rod* (switchable mirror only),
8
Analyser*,
9
Adjustment window*
