Abstract:

The electrical impedance tomography technique is studied with the thorax model, and the threedimensional cylinder model is built. The forward pr

oblemis completed by finite element method. The potential on the edge reflects the change of the internal impedance. The inverse problem is analyzed by the modefied NewtonRaphson algorithm based on homotopy theory. The impedance distribution is obtained in the inverse problem which approaches the true one. It shows that this mothod is suitable for the inverse problem of the electrical impedance tomography.

Key words: electrical impedance tomography; forward problem; inve rse problem; thre edimensional cylinder model; finite element method; homotopy theory; NewtonRaphson algorithm