Spatial resolution and noise tradeoffs in pinhole imaging system design: a density estimation approach

This paper analyzes the tradeo between spatial resolution and noise for simple pinhole imaging systems with photon-counting detectors. We consider image recovery algorithms based on density estimation methods using kernels that are based on apodized inverse filters. This approach allows a continuous-object, continuous-data treatment of the problem. The analysis shows that the pinhole size that minimizes the estimate variance for a specied reconstructed spatial resolution is directly proportional to that spatial resolution. For a Gaussian pinhole, the variance-minimizing full-width half maximum (FWHM) of the pinhole equals the desired object spatial resolution divided by p2. Simulation results confirm this conclusion empirically. The general approach is a potentially useful addition to the collection of tools available for imaging system design.