A convex mirror bends light as it reflects the light, and the farther away a point is from the center, the more the light is bent. As a result, an image formed in a convex mirror is smaller than an image in a plane (flat) mirror. Because the image is smaller, more images can fit onto the mirror, so a convex mirror provides for a larger field of view than a plane mirror. They are used whenever a mirror with a large field of view is needed to observe traffic.