A lidar sensor, especially for motor vehicles, having a light source, a movable deflection mirror for producing a scanning beam that sweeps across a monitored space by deflecting a light beam emitted by the light source, and having an optical receiver for detecting light reflected by an object hit by the scanning beam in the monitored space. The light source and the deflection mirror are adapted for using the deflected light beam to scan an array of micro-optical elements, each of which, in response to being impinged upon by this light beam, widens it into a divergent beam; and, configured at a distance from the array of micro-optical elements, is a light-concentrating element that transforms the divergent beam into a beam which forms the scanning beam and whose beam diameter is larger than that of the deflected beam.