Novel phase-shifting algorithm to achieve high-speed long-depth range probing by frequency domain optical coherence tomography

There has been a long discussion if Fourier Domain Optical Coherence Tomography (FDOCT) is competitive to nowadays standard time domain systems. Still the main points were autocorrelation terms that obscured the object information and degraded the sensitivity and signal to noise ratio. By exploiting the phase information of the interferograms, it was possible to remove those autocorrelation terms and to double the measurement range. However standard phase retrieval algorithms need three to five interferograms. We present a novel technique that allows removing the coherent noise terms together with doubling the measurement range with only two recorded interferograms. In addition the measured system sensitivity of 94dB shows that the performance of FDOCT is comparable to that of time domain OCT (TDOCT) setups.