Operation Manual

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3.22 Changing the size of the aperture diaphragm (Fig. 42-2)
Ɣ The aperture diaphragm determines the illuminated in the back focal plane of the microscope.
Ɣ Pull or Push aperture diaphragm adjustment lever to change the size of the field aperture
diaphragm. For normal observation, just the aperture diaphragm
Ɣ Closing the aperture diaphragm will reduce the resolution but enlarge the depth of focus of the
microscope
(Fig. 42-1) (Fig. 42-2)
3.23 Filter Blocks
A cube shaped modules that hold a matched set of fluorescence filters including excitation(EX),
barrier-emission (BA) and a dichroic mirror (DM).
The excitation filter allows transmission of light at a wavelength within the absorption spectrumof the dye
and rejects light at wavelengths within the emission spectrum of the dye, which couldbe reflected by the
specimen and incorrectly detected as emission energy.
A barrier filter allows the transmission of light at wavelengths within the emission spectrum of the dye
and rejects light at wavelengths within the absorption spectrum of the dye, which could be detected as
emission energy.
A dichroic mirror is placed at a 45º angle relative to the incoming excitation light; the dichroic mirror
performs two functions: it reflects the shorter wavelength exciting radiation light to the specimen and
transmits the longer wavelength fluorescence.