Nanosurf easyScan 2 AFM, Руководство по эксплуатации

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T
HE
O
PERATING MODE PANEL
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Dynamic Force mode
In addition to the same Operating mode and the User Input section as in
the static operating mode, two sections of parameters may be available,
depending on the user interface mode.
The dynamic force mode parameters can either be set manually or deter-
mined using an automatic search procedure. The automatic search starts
with the coarse measurement of a cantilever resonance curve (figure
Deter-
mination of the vibration frequency ). Throughout this measurement, the
cantilever is excited with a fixed amplitude, whilst the excitation frequency
is varied. The resonance curve contains a measurement of the resulting can-
tilever vibration as a function of the excitation frequency. When the search
is successful, the resonance curve contains a single peak at the free resonance
frequency of the cantilever. Afterward, a second, fine-tuning search is per-
formed in a 3 kHz frequency range around the resonance frequency
detected in the coarse search.
The computer adjusts the value of Vibration frequency so that the canti-
lever vibration amplitude is reduced by the amount set in ‘Amplitude reduc-
tion’ in the Freq. Peak Search section.
Mode Properties (Easy, Standard, Advanced)
Free vibration amplitude (Easy, Standard, Advanced)
The desired reference amplitude of the cantilever vibration. The cantilever
vibrates at this amplitude when it is far away from the sample. The excita-
Determination of the vibration frequency
frequency
vibr
ati
on amplitu
d
e
free resonance
frequency
vibration
frequency
amplitude
reduction