Blind spot detection systems use either radar or rear-looking video cameras to detect vehicles in the driver's blind spot. The systems only flag moving vehicles; they do not react to fixed objects such as traffic signs at the roadside that the subject vehicle is passing.
Detectors are located on both sides of the vehicle to facilitate safe lane change manoeuvres. The system only identifies objects in close proximity, to the vehicle. Generally, the system will illuminate a warning light, often located on the appropriate side mirror, to advise the driver of the presence of the adjacent vehicle. Some systems vibrate the steering wheel if the driver attempts to initiate an unsafe passing manoeuvre.
Systems with video cameras as detectors use computer-based image processing to identify objects of interest in the field of view and issue appropriate warnings.
Some systems feature powered side mirrors that, when a turn signal is activated, swivel outwards to provide a view outside of the regular field of view.
Vehicles in the driver of the green car's blind spot are detected
and the driver alerted that it is not safe to change lanes