NT-MDT Solver PRO, Инструкция по эксплуатации

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Chapter 2. Performing Measurements
Fig. 2-2
c. In the control panel of
Resonance tab make the following changes (Fig. 2-3):
-
In
Response signal
drop-down list select
Mag
.
-
Set the range (
From
…
To
) to include several cantilever resonance frequencies.
The second and third resonance frequencies are related to the first one as
f
1
/
f
0
=6.22 and
f
2
/
f
0
=17.5. So, with the exemplary frequency
f
0
=28 of the contact
probe the operating range should be taken as
From
= 0 kHz,
To
= 600 kHz.
-
Clear the
Auto peak find
check box.
-
Set Amplitude parameter equal to
1
V ×
1
.
-
Set the lock-in amplifier gain ( Gain parameter
)
equal to
10
.
Fig. 2-3
d. Click
Run
button to plot the frequency response of cantilever oscillation amplitude
(
Mag
signal), see Fig. 2-4, Fig. 2-5. On the resulting response apart from the peaks
corresponding to the cantilever resonance frequencies, spurious peaks may appear
owing to resonance oscillations of the piezodriver exciting the cantilever.
e. By narrowing
From
…
To
range adjust it to cover the frequency range
corresponding to a chosen AFAM resonance mode (n=1, n=2, …). In the given
example the range was chosen between the first,
f
0
, and the second,
f
1
, resonance
peaks related to the first mode. The cantilever contact resonance frequencies
(
, ) shall lie between the resonance frequencies of the cantilever
oscillations in the free state:
f
0
< <
f
1
;
f
1
< <
f
2
.
AFAM
n
f
1

AFAM
n
f
2

AFAM
n
f
1

AFAM
n
f
2

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