A sensor system includes an optical aperture, a light source configured to generate a light pulse along a first optical path, a reflective surface configured to reflect the light pulse from the first optical path to a second optical path for passing through the optical aperture, a beam steering device positioned in the optical aperture and configured to steer the light pulse along different directions to one or more objects in an angle of view of the sensor system, a detector configured to receive a reflected light pulse and convert the reflected light pulse into an electrical signal, the reflected light pulse being reflected back from the one or more objects and passed through the beam steer device, and a spatial filtering device positioned between the beam steering device and the detector to block undesirable light in both the light pulse and the reflected light pulse.