Dual spectrometer-based ultra-broadband spectral domain optical coherence tomography at 1450nm

Imaging deep in scattering samples with high resolution is potentially useful in a wide range of biomedical applications. In order to accomplish this, we utilize two off-the-shelf spectrometers centered at ~1300 nm and ~1550 nm along with a simple fiber-based interferometer and a supercontinuum source to synthesize an effective bandwidth of ~400 nm centered at ~1450 nm. A portion of the spectrum was missing and was filled-in using the gapped-data amplitude and phase estimation method. The axial resolution when using only the 1300 nm or 1550 nm spectrometer was 10.3 μm or 14.8 μm respectively, while the combined spectra yielded a 5.4 μm resolution in air while still maintaining a ~3.5 mm imaging range.