Abstract
We present a nonnegatively constrained iterative method formulated by discretizing nonlinear differential equations in a continuous-time image reconstruction (CIR) system for computed tomography (CT). The method of using the discretization has a simple structure, and is based on the continuous approach for an ill-posed inverse problem; therefore, we expect that the method of using the discretization produces better-quality images quickly and easily against the conventional methods. We give proof of the convergence of a desired solution in the discretized CIR system, theoretically. The theory is illustrated through experiments with a simulated phantom and projection data acquired from an X-ray CT scanner.
