92
Halogen
lamp
Collector setting, diffusing screens
Halogen, Hg and Xe lamp s:
Adjust the collector (61.6) until the bright area is
uniformly illuminated. Switch the microscope
back to object observation; the diffusing screen(s)
can be engaged (only with halogen lamp) to
check whether the image is homogeneously
illuminated (use a homogeneous specimen
section if possible and a low-power objective).
Use a grooved diffusing screen for the Xe 150 W
lamp.
Fig. 62
Lamp adjustment
a
direct filament image focused, but decentered
b
direct filament image in the right position
c
reflected and direct filament image in the right position
a
b
c
Hg 50
lamp
Hg 100
and Xe
lamp
