Toyota has extended warranty for certain models for this same problem, but not for Prius. My car has 117,000 miles and this problem has been going on for at least the last 25,000 miles (based upon orange warning triangle). According to dealer, problem is with rings (which is the recall for other Toyota cars). Also, according to dealer, this is a real problem for other Prius owners with 100,000+ miles.
Concave lenses in glasses correct this shortfall by spreading out the light before it reaches the eye, thereby enabling the person using them to see distant objects more clearly. Cameras. Camera manufacturers use combinations of concave and convex lenses to improve the quality of photographs.
DEFINITION 2: Light rays originally headed towards the focal point on the other side of a concave lens are bent, emerging parallel to the axis. This is just the reverse of the definition above, but will be very important in determining how and where images are formed by a concave lens.