A java distributed acquisition system for PET and SPECT imaging

The Detector and Imaging Group at Jefferson Lab is developing various compact gamma cameras for clinical and preclinical systems. Both PET and SPECT systems are under development. To facilitate that development we have designed a highly flexible Java data acquisition tool that helps to minimize software induced dead-time while maintaining the highest possible data rates from our in house built ADCs. This tool interfaces with FPGA based multi-channel ADCs which our group has developed. Using this tool we are able to process data from a number of different detector types such as the SPECT Awake Animal Imaging system at Johns Hopkins University; as well as our PET systems at West Virginia University (WVU), the University of Florida (UF), and the National Technical University of Athens. Because of the inherent flexibility of our processing software, we are also able adjust detector readout parameters during operation to provide the best possible data presentation and calibration parameters. We are using the readout capability of this software with Kmax to provide a user friendly display of detector outputs such as raw images and individual channel spectra. To accommodate the high rate nature of PET detector systems we designed this software to be scalable across an Ethernet network as well as for multi-CPU computer systems, and it also has the capability to synchronize many ADCs connected to multiple computers. We have incorporated this distributed design into the six computer PEM (Positron Emission Mammography)/PET system at WVU, and the three computer cardiac PET detector at UF.