Fast image reconstruction for high resolution CCD based gamma ray imaging

We are developing a high resolution gamma ray imager, specially for use in nuclear medicine. The use of collimators for high resolution imaging gives rise to low sensitivity at sub-mm resolutions. We propose the imager consists of a CCD with a pixel size of 44 μm, interfaced to coded apertures. A reconstruction code has been developed for 2D and 3D reconstructions from, initially, a single projection, producing longitudinal, coded aperture shadowgrams. The iterative reconstruction technique is based on the ML-EM algorithm. The code has been developed to work on cross-platforms, Linux, Windows, Solaris, with graphics implementation using the SDL library.