Suppression of scattering effect of optical CT image using point spread function

With the recent progress of an optical technology, the feasibility of the optical cross-sectional imaging of an animal body or an optical CT has been pointed out. The strong scattering at biological tissue is one of the most difficult problems to realize the optical CT. To suppress the scattering effect in a reconstructed image of the optical CT, a fundamental study has been conducted on the deconvolution technique using a point spread function (PSF). The image blurring due to the scattering can be considered as the convolution of the distribution of the absorption coefficient and the PSF of a scattering medium. Therefore, if we can find an appropriate PSF, we may be able to suppress the scattering effect by deconvolution using the PSF. In the conventional deconvolution technique, a single PSF defined according to the thickness of the scattering medium has been used. However, the suppression of the scattering effect has not been sufficient since the blurring effect is depth-dependent in the scattering medium. We developed a new technique to incorporate the depth-dependent PSF in the reconstruction process of the optical CT. In computer simulation, the effect of the scattering suppression was demonstrated in the reconstruction of the optical CT image.