Effects of temporal and spatial coherence on resolution in full-field optical coherence tomography

The contrast enhanced imaging of microscopic structures of tissue and the high-resolution optical sectional imaging of thin slices within tissue are two main advantages of full-field optical coherence tomography (FFOCT) over the conventional optical microscopy. In this work, first a detailed description of the development of FFOCT technique is reviewed. The imaging signal model of FFOCT is then described, which reveals the roles of both the light-intensity distribution in the pupil plane of the objective lenses and the light spectrum of the source on the system resolution. Then the effects of the temporal and spatial coherence on the lateral resolution and depth resolution of FFOCT are considered. Finally, the change of separation between the temporal coherence envelope and the longitudinal spatial coherence envelope is analyzed induced by the mismatch of the refractive index of tissue and the surrounding medium.