Final answer:
A diverging lens is thinner in the middle, causes parallel rays to spread out, and has a focal point where rays seem to originate. It can be analyzed using ray tracing.
Step-by-step explanation:
The type of lens that is thinner in the middle than at the edges and causes parallel rays of light to diverge as if from one point is known as a diverging lens. When parallel rays of light pass through a diverging lens, they bend away from the lens's optical axis. The focal point for a diverging lens is the point from which the diverging light rays appear to originate. This behavior can be understood through the technique of ray tracing, which graphically determines the paths taken by light rays through thin lenses according to the law of refraction. A thin lens allows light rays to refract, but it's thin enough to neglect effects such as dispersion and aberrations. A characteristic of a thin lens is that light rays passing through its center are deflected by a negligible amount and continue in the same direction.