Fig. 4
The acquisition methods for obtaining TOF offset calibration data. a Using a rotating line source. An emission from the line source (red) is detected by crystal pairs connecting via straight line through the point. b Using a scattering phantom (indicated in blue) and a point source. An emission from point source (red) is detected after scattering at 1 or 2. c Using an annulus shape source. The set of close LORs (in black) is averaged and used to calculate the average offset per detector pixel