Abstract: A sensor implemented with a single light sensing device detects ambient light levels and object motion. The sensor comprises an optical component assembly composed of a linear array of light sensitive elements, preferably photodiodes, positioned downstream of a segmented slit aperture device comprising a single, segmented slit, the slit length of which is oriented perpendicular to the length of the linear array. The individual photodiodes of the array provide motion detection capability in a direction perpendicular to the slit length. The slit aperture is segmented along the slit length to form multiple zones of sensor light responsivity that provide motion detection capability in a direction parallel to the slit length. An object moving in a direction parallel to the multiple slit aperture passes through one or more zones of sensor responsivity and thereby produces from the photodiodes a varying electrical signal from which object motion can be detected.