Monitoring of multimode imaging devices by use of optical low-coherence reflectometers in reflection and transmission modes

The broadband source of a high-precision optical low-coherence reflectometer is simultaneously employed in conventional reflection and transmission modes to monitor the internal properties of multimode imaging (MMI) devices. Using two carefully chosen examples, we show that this new methodology should permit precise assessment of the performance of MMI devices, including backreflection and internal reflection as well as the imbalance between output waveguides.