By the way, if you know, what are the kinds of detectors at the other end of the laser pulse that receive the signal? Are they like the pixels of a CCD but wit

By the way, if you know, what are the kinds of detectors at the other end of the laser pulse that receive the signal? Are they like the pixels of a CCD but without the need for periodic / time-bound readout? They just are like silicon photocells that can react at the femto(?)-second speed and turn it into pulses translated into electrons?