Constrained resolution enhancement in optical microscopic tomography

In an earlier work, we have developed a new principle of optical microscopic tomography, by which an inside optical density distribution of a 3-D biological sample can be visualized without physically slicing. However, since the system is angularly band-limited, the spatial resolution (especially, the longitudinal one) is poor. In this paper, we describe a numerical method to improve the resolution of the reconstructed 3-D image by constraining the reconstructed density to be nonnegative. The method requires much smaller computation complexity than the conventional quadratic programming when the number of variates (pixels or voxels) are large (in the case of 3-D imaging, for example, 100×100×100). Experimental results by the proposed method with real data of a biological sample are shown to demonstrate the effectiveness of this method.