The rear - mounted radar sensors continuously monitor your blind spots and a large area behind your car, day or night. (volvocars.com)
Also, the rearview mirror on the windshield doesn't seem big enough; you can't see the whole area behind the car unless you move your head back and forth. (articles.orlandosentinel.com)
The Audi parking system plus with reversing camera displays the area behind the car on the onboard monitor using an inconspicuously mounted camera. (ausmotive.com)