Modern luxury vehicles are available with a wide range of driver assistance technology and use a variety of sensors to power that tech. Lane departure warning systems use front-facing cameras to watch the lines painted on the road. Blind-spot monitoring uses sonar arrays to check the area around the vehicle for obstructions. Rear proximity detection also uses sonar arrays to detect objects behind a reversing vehicle. The 2013 Nissan Altima will be able handle all three of these functions with only one rear-facing camera.
Nissan's system uses a rear-facing camera that constantly watches the area behind and to the sides of the vehicle. By reading the vehicle's position between the painted lane markers on the road, it is able to serve as a lane departure warning system and can alert the driver of an unintentional drift out of the marked lane with a beep. The ultrawide lens is also able to see vehicles at the rear quarters of the Altima, the area known as the blind spot, and can audibly alert drivers to their presence.
Of course, the most obvious use for this rear camera is as a rearview camera that gives the driver a view of the area behind the vehicle when reversing. If motion is detected within the camera's field of view -- for example, if a pedestrian wanders into the Altima's path -- the vehicle is able to audibly alert the driver.
Perhaps the most interesting feature here is that the 2013 Altima's rear camera can clean itself. Periodically, a droplet of windshield cleaning fluid is dripped onto the lens. Next, an air compressor puffs a burst of air onto the lens to clean and dry it.
This all happens automatically and, presumably, keeps the clean lens from reporting false positives or missing critical details.
By combining all of these features into one camera with some clever software, Nissan should be able to implement all of them on the 2013 Altima as part of a single relatively inexpensive driver aid package. However, pricing and packaging for this potential option have not been announced.