Setting the Position of the Polarizing Filter
Setting a state of Polarization
Agilent
8169A
Polarization Controller, Second Edition
21
Setting the Position of the
Polarizing Filter
The polarizing filter should be set to maximize the signal. This means
aligning the polarizing filter with the greatest linear polarization of the
source. (Light from laser sources is elliptically polarized).
Figure 4 Power as a function of the angle of linear polarization for laser light
1
Connect the output of the polarization controller to a power meter.
2
With all the instruments turned on, press
on the polarizatio controller.
This resets the positions of all the plates.
3
Select the polarization filter. You may need to press
and/or Pol if the filter
is not already selected.
4
Move the filter to find the maximum signal through the polarization controller.
One way of doing this is
a
Press the right Cursor key twice to select the units digit.
b
Watching the power meter, and using the Modify knob, adjust the angle of
the polarization filter, until you are in the area of one of the maxima.
c
Select the tenths digit.
d
Watching the power meter, and using the Modify knob, adjust the angle of
the polarization filter, until you find the maximum.
e
Select the hundredths digit, and adjust the angle of the polarization filter if
necessary to get the absolute maximum.
5
Disconnect the power meter, and connect to your DUT, and the rest of your
measurement setup, making sure to move the fibers as little as possible.