7 PICOSCALE CONTROL GUI
7.2 Adjustment
Figure 7.5:
PICO
SCALE
Adjustment Panel.
The three input channels of the
PICO
SCALE
can be configured in the
Adjustment Monitor
. The goal
of the adjustment is to align the interferometer heads in front of the target mirrors and optimize
the signal quality. Furthermor
e, internal subsystems of the
PICO
SCALE
device are optimized
to achieve highest possible resolution and accuracy of position measurements. Note that a full-
access connection has to be established to perform the adjustment procedure. Each channel can
be enabled and disabled with the corresponding check box below the graphs before the manual
adjustment is started. With the drop-down menu besides each check box the connected head type
can be con
fi
gured. The head type is written on the housing of each head and in the corresponding
data sheet. For older heads, please use the standard head type C01.
On the upper left side of the GU
I
in
fi
gure 7.5 the
fi
ber length can be changed. A standard sensor
head is delivered with a
fi
ber length of about 1600 mm.
I
f additional extension
fi
bers are used
the length should be inserted in the
fi
eld
Extension fiber [mm]
. Furthermore, the
beam interrupt
tolerance
can be set: The
PICO
SCALE
generates so-called
beam interrupt
events when the signal
quality drops below a certain threshold. The
PICO
SCALE
can be made more tolerant to these
events by increasing the value of the
beam interrupt tolerance
(default: 33%). A value of 100%
means that no beam interrupt events are produced any more.
Channel enabling/disabling and con
fi
guration of the head type must be done before the adjust-
ment process is initiated, the beam interrupt tolerance can be set at any point.
The manual adjustment procedure is started by clicking on the
Start Manual Adjustment
button.
Figure 7.5 shows the
Adjustment Monitor
with one Lissajous graph for each channel after the man-
ual adjustment is started. Enter the expected working range (which in
fl
uences the modulation
amplitude) and con
fi
rm it by clicking
Set
. The more precise you enter the expected working range,
the higher the accuracy of your measurement will be.
53
PicoScale User Manual
