Evaluation of Absolute and Real Signal Values in Reconstruction of Electrical Impedance Tomography Images

We explore the differences between real and absolute values of signals in Electrical Impedance Tomography image reconstruction, with a focus on their impact on image quality and accuracy.Simulations were conducted using a finite element mesh model containing three inclusions with varying conductivity values.The inclusions representing regions with moderate, poor, and high conductivity were carefully chosen to create sharp contrasts in conductivity.In the experiment, 16 electrodes were placed around a circle, a current injection pattern was applied, and the resulting boundary voltages were recorded.The reconstruction based on absolute signal values, depicted in the center image, tended to smooth out sharp conductivity contrasts, leading to significant artifacts and reduced accuracy in localizing the inclusions.In contrast, the reconstruction based on real signal values provided an accurate representation of the true conductivity distribution, improving the localization of the inclusions.The results underscore the critical role of considering the real component of the signal in electrical impedance tomography image reconstruction to achieve improved accuracy and higher fidelity in the resulting images.