Optimal spectral reshaping for resolution improvement in optical coherence tomography.

We analyze the resolution limit that can be achieved by means of spectral reshaping in optical coherence tomography images and demonstrate that the resolution can be improved by means of modelessly reshaping the source spectrum in postprocessing. We show that the optimal spectrum has a priori surprising "crater-like" shape, providing 0.74 micron axial resolution in free space. This represents ~50% improvement compared to resolution using the original spectrum of a white light lamp.