The metabolism of substances in a tumor is inherently time-dependent and involves a variety of physiological and biochemical processes. Thus, the ability to observe physiological and biochemical processes with each tracer in the living organism in a dynamic, simultaneous mode opens up fascinating possibilities for both fundamental research and routine diagnostic applications. In hardware aspect, a high-speed, high-accuracy timing calibration method has been developed, where the timing resolution was improved 80%. Given the poisson nature of photo counting measurements, Prof. Liu Huafeng group from Dept. of Opital Engineering present a reconstruction framework that integrates sparsity penalty on dictionary into a maximum likelihood estimator under the support as the special vital instrument program of NSFC foundation in 2014.