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Performance Tests
V. Polarization Dependent Loss (PDL): Optional
a. Select the λ/2 Retarder Plate.
Press
λ/2
b. Modify the
λ/2 plate setting to the same angle as the
polarization filter found in item 6c.
c. Press ENTER
d. Note the angle as "λ/2 Plate Setting, Linear Horizontal
Polarization" in the Test Record.
Determine settings for Linear Vertical, Linear Diagonal, and
Right Hand Circular Polarization
9. In order to get the required polarization, the
λ/2 and λ/4 retarder
plates need to be set to the appropriate values. The corrected
positions of the polarizer plates depend on the actual wavelength
and have to be taken from Table D-3.
In the case of Linear Horizontal polarized light no correction is
to be done. The table lists corrections for every 20 nm step. For
wavelengths between listed values, a linear approximation
should be used.
The value taken from the table (possible by approximation) is to
be added to the values of the
λ/4 and λ/2 retarder plate setting for
Linear Horizontal polarized light determined in steps 7. and 8.
respectively:
• Get the values for the wavelength dependent offset
positions for each type of polarization from Table D-3.
• Add these values to those for Linear Horizontal polarized
light.
• Note the calculated "corrected wavelength dependent
position" values in the Test Record for the
λ/4 Plate
Setting and the
λ/2 Plate setting for Linear Vertical,
Linear Diagonal and Right Hand Circular polarization.
Example: actual wavelength 1552 nm. Find the maximum
transmission for the Linear Horizontal polarized light at a
polarization filter setting of 15.4
°.
In Table D-3, wavelength dependent positions can be found and