Reflection

2.6 Curved mirrors

Convex mirrors

Convex mirrors affect the path of light in much the same way as concave mirrors. First, one should note that the center of curvature is on the opposite side of the reflecting surface. We saw earlier that convex mirrors don't focus light to a point but rather cause the light rays to diverge. Rays parallel to the principal axis diverge as if they were coming from a point behind the mirror. This point is also called the focus. Since light never actually reaches this focus, we will call it the virtual focus.

• Incident rays directed at the focus are reflected parallel to the principal axis (red).
• Incident rays parallel to the principal axis are reflected as if they originated at the focus (blue).
• Incident rays directed at the center of curvature are reflected back on themselves (yellow).