Efficient polarization independent OCT system using a single reference arm design

We present an efficient polarization-independent optical coherence tomography (PI-OCT) system that reduces signal fading due to polarization variations by over 92%. Unlike traditional PI systems that require separate reference arms for orthogonal polarizations, our design employs only one. A fiber delay unit employed within the reference arm creates two depth-encoded channels, allowing the orthogonal polarization signals returning from the sample to interfere with the reference light at different depths. Combining these two signals produces a polarization-insensitive image. By utilizing a single-channel balanced detector instead of polarization diversity detectors further simplifies this design and reduces its cost.