PSY-201 User Guide
GP-UM-PSY-201-11
Page 23 of 105
dSOP Threshold Range: 0 to 180° from target SOP on Poincaré sphere Default: 0°
Tracking status trigger:
TTL level low = within threshold (SOP inside blue area)
TTL level high = out of threshold (SOP outside blue area)
Electrical connection: Pin 8 on DB15 expansion connector
Figure 14 Tracking status threshold
Trace Circle
Trace circle is a preprogrammed function that traces a great circle around the sphere,
centered on one of the basis SOPs as the principal state of polarization (PSP). LP90°, LP135°, and
LHC rotate in opposite directions from LP0°, LP45°, and RHC, respectively. The trace direction
follows the right hand rule (counterclockwise rotation when looking into the specified SOP). The
step size and dwell time at each step can be configured before starting. While the tracing is in
process, the user can pause or exit the function using softkey options. While the function is
paused, the user can continue, restart, or exit the function using softkey options. Use the arrow
buttons to cycle through softkey options.
While the function is paused, setup parameters cannot be changed. Exit the function to
change setup parameters such as step size or dwell time.
The function can also be enabled/disabled using the
■
/
►
button. The circle trace icon
indicates the enable/disable status of the function. Icon = enabled; no icon = disabled.
Circle defined by dSOP threshold
Target SOP
