A gesture sensing device includes one or more sensors and a processor for processing sensed voltages output from the sensors based on ambient light and/or reflected light received by the sensors. The processor determines an ambient light level and/or a distance between the target and the sensors such that, if the ambient light level exceeds an ambient light threshold and/or the distance is less than a distance threshold, the processor determines the motion of a target relative to the sensors based on the ambient light instead of the reflected light.