Imaging sensor device using an array of single-photon avalanche diode photodetectors

The invention relates to an Imaging sensor device in a stacked arrangement comprising: - a pixel array tier comprising a plurality of pixel segments each having a plurality of pixels for photon detection each providing a digital pixel output; - a processing tier comprising a number of processing cores each associated with one of the plurality of pixel segments to receive the pixel outputs of the pixels of the respective pixel segment, wherein the processing cores are each in bidirectional communication with one or more neighboring processing cores, wherein the processing cores are each configured to receive pixel outputs of the pixels of the associated pixel segments and to distribute processing of pixel outputs between the processing core and the at least one of the neighboring processing cores as neighboring processing cores.