Embodiments are directed toward measuring a three dimensional range to a target. A transmitter emits light toward the target. An aperture may receive light reflections from the target. The aperture may direct the reflections toward a sensor that comprises rows of pixels that have columns. The sensor is offset a predetermined distance from the transmitter. Anticipated arrival times of the reflections on the sensor are based on the departure times and the predetermined offset distance. A portion of the pixels are sequentially activated based on the anticipated arrival times. The target's three dimensional range measurement is based on the reflections detected by the portion of the pixels.