Santec PEM-320, Operation Manual

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POLARIZATION EXTINCTION RATIO METER PEM-320
4-1
4
Principle of Operation
The above diagram shows the design of the PEM-320 unit. The optical fiber is connected through the
input connector. The light from the fiber is then collimated by a lens, and after passing through a
rotating polarizer is incident on the photodetector. In units with the high power option fitted, an
optical attenuator is placed prior to the rotating polarizer. This attenuator is specially designed to be
polarization independent to ensure that it does not compromise the performance of the free space
optics design.
0
180
1 measurement period
max
min
Optical Power
Polarizer Angle (deg)