Methods, apparatus and systems for polarization extinction ratio detection of multi-fiber devices

A method of determining a polarization extinction ratio (PER) of multiple fibers in a multi-fiber device, the method comprising:

• (a) coupling the multi-fiber device to a PER detector;
• (b) receiving, at the PER detector, light from a fiber of the multi-fiber device;
• (c) passing the received light through a rotating polarizer and at least one wide-area optical element of the PER detector to generate a beam that is focused on a photodetector of the PER detector, the rotating polarizer rotating with respect to the photodetector;
• (d) converting, at the photodetector, the beam into an electrical signal;
• (e) generating the PER for the fiber based on the electrical signal generated by the photodetector;
• and
• (f) while the multi-fiber device is coupled to the PER detector, repeating (b) to (e) for a different fiber of the multi-fiber device.

A system for determining a polarization extinction ratio (PER) of each fiber in a multi-fiber device, the system comprising:

• a light source;
• a multi-fiber switching unit coupled to the light source;
• a first adapter for coupling a first end of a multi-fiber device to the multi-fiber switching unit, the multi-fiber switching unit configured to automatically cause the light source to sequentially provide light to each fiber of the multi-fiber device;
• a second adaptor for coupling a second end of the multi-fiber device to a PER detector, the PER detector comprising:
• a photodetector for converting light to an electrical signal,
• a polarizer that is rotatable with respect to the photodetector, and
• at least one passive wide-area optical element;
• wherein the photodetector, polarizer and at least one passive wide area optical element are positioned such that light output by any fiber of the multi-fiber device follows an optical path through the polarizer and the at least one wide-area optical element to generate a beam that is focused on the photodetector;
• and
• a measurement device coupled to the photodetector, the measurement device configured to generate the PER for each fiber of the multi-fiber device based on the electrical signal generated by the photodetector while that fiber is outputting light.