User manual

25
Leica MacroFluo – Operation
3.8.5 Filter blocks
The filter turret (14.1) can accommodate up to four
filter blocks (ch. 2.10). These filter blocks contain
the excitation filter, dichromatic beam-splitting
mirror and suppression filter.
– The excitation filter selects exactly those wave-
lengths from the beam selection of the light
source that are used for exciting the fluores-
cence. This is made possible by highest trans-
missivity in the excitation range, while using the
highest possible suppression effect in other
wavelength ranges.
– The dichromatic beam-splitting mirror reflects
the short-wave excitation radiation to the spec-
imen, while being transparent for the fluores-
cent light emitted from the specimen.
– The suppression filter blocks excitation light
dispersed by the specimen and entering in the
objective. However, it features the highest
transmissivity for the specific fluorescence
radiation.
3.8.2 Aperture diaphragm
The aperture diaphragm is used for setting the
contrast for reflecting specimens or, if neces-
sary, for reducing the excitation radiation to
prevent excessive bleaching of the specimens.
왘 Aperture diaphragm A (14.3): Fully opened for
fluorescence.
To reduce reflections and protect specimens,
restrict the aperture diaphragm (14.3) as
needed.
3.8.3 Light stop
If you want to work with transmitted light or
incident light without fluorescence:
– Close the light stop (14.4) if all 4 positions in
the filter turret are occupied with filter blocks.
If there are empty positions in the filter turret,
you can also switch over to the empty posi-
tion using the filter wheel (14.1).
3.8.4 Filter BG38
The BG38 filter prevents a slight red background
in the image. If this does not pose a problem,
the BG38 filter (14.5) can be swung out to use
the full lamp power for exciting the fluores-
cence.