Cross-free in both lateral and axial directions for Fourier-domain full-field optical coherence tomography

Fourier-domain full-field optical coherence tomography has the advantages of high resolution and parallel detection. However, using parallel detection can result in optical crosstalk. Toward minimizing crosstalk, we implemented a very fast deformable membrane (DM) that introduces random phase illumination, which can effectively reduce the crosstalk by washing out fringes originating from multiply scattered light. However, although the application of DM has reduced the crosstalk problem in parallel detection to a certain extent, there will still be a lot of background noise, which may come from the circadian rhythm of the sample and multiple scattered photons. The problem could be solved by employing adaptive singular value decomposition (SVD) filtering. We also combined SVD with the cumulative sum method, which can significanlty improve image resolution. Also, the random phase introduced by DM in the spectral domain will cause axial crosstalk after an inverse Fourier transform. As far as we know, we are the first team to notice axial crosstalk and propose that this problem can be solved by controlling the deformation range of DM. We have carried out a theoretical analysis of the above methods and verified its feasibility by simulation.