Device and process for nuclear location by weighted barycenter calculation using parallel-operating detectors, and application to gamma cameras

Process for determining the position P0 (X0, Y0) of an event in an X, Y coordinate system making use of a set of N photodetectors laid out in matrix form in rows and columns, an arbitrary detector in a column with rank i and a row with rank j being identifiable in the coordinate system, the event inducing a signal in the N photodetectors, comprising sampling, further comprising digitization of the signals output by each photodetector, and a summation of the digitized samples:

• a) a step in which the sliding sum of the digitized samples is stored, the current sum being stored each time that samples are added, the final sum representing the energy Ni,j output by the sensor for each photodetector in a column of rank i and a row of rank j;
• b) a step in which the following are determined for each column of rank i:
• the contribution of the column to total energy induced by the event in the set of photodetectors,
• the contribution of the column to the X value of the center of gravity of the event,
• the contribution of the column to the Y value of the center of gravity of the event,
• c) a step in which the following are determined:
• the total energy induced by the event in the set of photodetectors, by summation of the contributions of each column calculated in step b,
• the coordinates of the center of gravity (XO, YO) of the event with respect to the N photodetectors.