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NanoTrak Autoalignment Controller
Feedback Signal Type
- This parameter sets the type of feedback signal used when
operating the HV amplifier channels in closed loop operation.
Two types of feedback signal are supported:
Legacy AC (Strain Gauge)
- The AC Strain Gauge mode refers to the use of AC
excited strain gauge feedback signals as generated by the complete range of
Thorlabs piezo actuators and piezo equipped multi axis stages.
Differential DC
- It is possible to set the feedback signal type to DC 0 – 10V. This
configures the feedback circuit to accept a differential 0-10V DC feedback signal
in order to control position output. This latter feedback mode is available for use
with third party piezo positioning systems capable of generating a standard
voltage position feedback signal.
3.10 Programmed Operation - NanoTrak
3.10.1 A Typical Alignment using the NanoTrak
1) In the NanoTrak GUI, set the ‘Scan Circle Diameter’
control to approximately mid-position.
2) Press the ‘Latch’ button to select Latch mode and check that the Latch indicator
LED is lit.
3) Click and drag to centre the scan circle in the display.
4) Press the ‘Auto’ button to select ‘Auto’ mode. Ensure that the ‘Auto’ LED is lit.
5) Adjust the actuator on the positioning stage such that the fibers are spaced well
apart, with zero power transmission between them. (Alternatively, switch off or
obscure the optical power source). Make a note of the bar graph displays of
relative power input and range. Since the optical source has been removed, only
background noise is registered.
6) Use the actuators to bring the fiber tips together, until the display shows a
significant increase indicating that the power has risen above the background level.
7) Press the ‘Track’ button to select Track mode. Check that the ‘Tracking’ indicator
is lit and that the circle moves towards the position of maximum power (center
screen). The NanoTrak has now positioned the fiber to give the maximum optical
power transmission.
Note
On modular hardware (and later versions of benchtop hardware), the function of the
pin connections on the 9-way D-type feedback connector is dependent on the
feedback mode selected. Refer to the pin-out tables in Section 4.2.6. for details.
Note
Familiarize yourself with NanoTrak operation from the GUI panel before attempting
programmed operation from the Controller PC.