An object detection system for object detection within a field of view of a sensor , comprising: a light source for providing detection illumination to the field of view; a sensor adapted to sense a reflected light from the field of view when illuminated by said detection illumination provided by the light source , wherein the sensor is a time of flight camera; and a controller for processing the sensed reflected light and for performing time of flight analysis of the sensed reflected light to provide distance information in relation to objects within the field of view, wherein the controller is adapted to derive a signal quality parameter relating to the distance information and to control the light source intensity in dependence on the signal quality parameter, the signal quality parameter comprising a signal to noise ratio, or a controller for processing the sensed reflected light and for performing time of flight analysis of the sensed reflected light to provide presence information in relation to objects within the field of view, wherein the controller is adapted to derive a signal quality parameter relating to the presence information and to control the intensity of the detection illumination provided by the light source in dependence on the signal quality parameter, the signal quality parameter comprising a signal to noise ratio, characterized in that the controller is adapted to compare the signal quality parameter with a target value and to control the intensity of the detection illumination provided by the light source in response to the comparison, and wherein the target value is the required signal quality parameter for a particular scene and object to be detected. a light source for providing detection illumination to the field of view; a sensor adapted to sense a reflected light from the field of view when illuminated by said detection illumination provided by the light source , wherein the sensor is a time of flight camera; and a controller for processing the sensed reflected light and for performing time of flight analysis of the sensed reflected light to provide distance information in relation to objects within the field of view, wherein the controller is adapted to derive a signal quality parameter relating to the distance information and to control the light source intensity in dependence on the signal quality parameter, the signal quality parameter comprising a signal to noise ratio, or a controller for processing the sensed reflected light and for performing time of flight analysis of the sensed reflected light to provide presence information in relation to objects within the field of view, wherein the controller is adapted to derive a signal quality parameter relating to the presence information and to control the intensity of the detection illumination provided by the light source in dependence on the signal quality parameter, the signal quality parameter comprising a signal to noise ratio, characterized in that the controller is adapted to compare the signal quality parameter with a target value and to control the intensity of the detection illumination provided by the light source in response to the comparison, and wherein the target value is the required signal quality parameter for a particular scene and object to be detected. <EOS>