The new Nissan Altima rearview camera can virtually see backwards, forwards, and sideways at the same time—all with a single wide-angle lens—and it reports to a computer with sophisticated software to interpret what it sees. As a result, it not only performs the function of a conventional rearview camera, but lots more.
With the wide-angle imaging, the computer can check for cars in the driver’s blind spots, and can identify movement, perhaps by a pedestrian, into the path of the car when the transmission is shifted into reverse. Finally, the camera looks at the lane markings in the rear and the computer interprets any changes in alignment of the vehicle to produce a "virtual" front view, determining if it’s staying in lane or starting a forward drift into an adjacent lane. If the computer decides that the image data from the rear indicates there’s forward drift, it triggers the audible lane-departure warning.
The rear view approach to determining vehicle lane position and possible forward drift is less “touchy” than the conventional front camera system, Nissan claims. So it is expected to produce more accurate indicators for the audible warning, reducing the frequent warnings from instantaneous minor miss-alignments, which lead to drivers turning off the system.
The camera shows images on a 4.0-in 3-D-like display between speedometer and tachometer. When another vehicle enters a blind-spot zone, the system begins by turning on an indicator light in the door close to the outside mirror and a warning on the display. If the driver moves the turn signal lever to indicate a turn in the direction of an occupied blind zone, the light flashes and a warning chime sounds.
The rear camera, located in the license plate mounting area, has a viewing range approximately 160º wide, and with four functions the lens must be really clean. If the computer determines the camera can’t see properly, it operates a modified windshield washer pump with a second function: spraying fluid through a port onto the lens. Following that, a rear-located mini-compressor blows air through a second port to clear off debris and cleaning fluid and dries the lens. If the cleaning operation doesn’t work, a dashboard warning illuminates.