Optical tomography at the microscopic scale by means of a numerical low-coherence holographic technique

We describe here a numerical application of the optical low- coherence holographic microscopy (OLCHM) technique. A low coherent source illuminates an object and the backscattered light interfere with a reference wave which optical path's length can be precisely adjusted. Holograms are recorded by a CCD camera and numerically reconstructed. With this technique optical tomography can be performed with a single scan along the optical axis. The transverse resolution of the reconstructed images mainly depends on the optics components used and approaches the diffraction limit. Using a Ti:Sapphire laser a depth resolution of about 30 micrometers has been achieved.