摘要

One of the main factors that limits the effective axial resolution of spectral domain optical coherence tomography in live tissue imaging is tissue-induced dispersion. In this work, first the methods are reviewed that have been proposed to compensate for the dispersion effects in various applications. Simple formulas are then derived that can be used to estimate the orders of the dispersion that may have significant influences. The formulas are then used to calculate relative contributions of various dispersion orders to the decrease of the axial resolution, in which the dispersion properties of water were employed as a first approximation to tissue. It is found that up to fourth-order dispersion should be compensated when the theoretical resolution approaches 1 mu m. The Wigner distributions of the interference spectral signals for an interface beneath a surface are presented, where the dispersion order contained in the interference signal can be discerned intuitively. The results are helpful for choosing the appropriate methods for dispersion compensation.