Simulation study on the image noise of diffuse reflective optical tomography

We study a diffuse reflective optical CT, in which continuous-wave sources and detectors are placed on the plane surface of the semi-infinite body. A simple Tikhonov regularization was adopted in the inverse problem, and the feasibility of the 3-dimensional reconstruction of the absorption coefficient change was demonstrated although the spatial resolution was shown to be degraded markedly with the depth. It is practically important to select appropriate regularization parameter value considering the trade-off between spatial resolution and the noise of the reconstructed image. In this report, we demonstrate depth-dependent image noise, and analyze its dependency on the regularization parameter and the measurement noise.