Polarity testing and Insertion Loss (IL) testing are crucial steps in the production and assessment of multi-stranded fiber optic cables. With certain setups, IL can be measured while verifying polarity.
The IL test measures the amount of light lost when traveling through the DUT en route to the detector. A test setup that uses a multichannel source and multichannel power meter evaluates the light paths of a multifiber device under test (DUT) one at a time. If any of the fibers are crossed or broken, light does not reach the OPM on the expected channel resulting in dark values. Using an Insertion Loss and Return Loss (RL) meter as the source instrument and a multichannel power meter as the detector allows for 3-in-1 IL, RL, and polarity evaluation.