Direct reconstruction of complex refractive index distribution from boundary measurements

Abstract

AbstractWe obtain the reconstruction of the refractive index distribution of body based on the intensity and normal derivative of the intensity measurements. The Helmholtz equation is inverted either directly or indirectly through repeated implementation of the forward operator and its adjoint, for recovering the complex refractive index distribution. We do not adopt the procedure of recovery of phase (normally required for complete knowledge distribution). We derive certain sensitivity relations which is used for the easy computation of the Jacobian. Our procedure successfully reconstructs the real and imaginary parts of the complex refractive index from the measurement of the two data types derived from the complex amplitude at the boundary. Our other interest is the reconstruction of the spectroscopic variations of optical absorption coefficients and visco‐elastic properties of a tissue which is extremely useful in diagnostic medicines. The research is on progress and some results are available. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)