An integrated imager circuit having a monolithic array of single photon avalanche diodes (SPADs) for capturing an image of a scene when said scene is hit by an optical pulse. The array has a plurality of SPADs connected to 2D readout circuits which determines the intensity of the light reflected by the scene by counting the number of photons received by the SPADs during a period of time. A plurality of SPADs connected to 3D readout circuits determines the distance to the scene by determining the elapsed time between the emission of each pulse and reception of the corresponding reflected photons.