Abstract: An improved optical observation system for a movable body in space which comprises a scanning mirror, imaging optics and a sensor formed by at least one array of photodetectors arranged along a plurality of rows parallel to the apparent displacement of the image points. The electric signals from the photodetectors are driven to be transferred from one photodetector to the following along each row with a velocity equal to the velocity of the apparent displacement of the image points. An advantageous embodiment for the sensor is also disclosed together with suitable means for multiplexing the output signals developed at the ends of the rows onto a unique output line.