Certified Paraoptometric (CPO) Practice Exam 2025

What does a divergent lens create with parallel light rays?

1. Convergence

2. Focus

3. Divergence

4. Reflection

The correct answer is: Divergence

A divergent lens is specifically designed to spread out light rays that pass through it. When parallel light rays enter a divergent lens, instead of converging to a point, the lens causes the rays to diverge, or spread apart. This action creates the impression that the light rays are emanating from a particular focal point, known as the virtual focus, which is located on the same side of the lens as the incoming light. In contrast, convergence refers to the behavior of converging lenses, which bring parallel rays together to meet at a focal point on the opposite side of the lens. Focus would typically relate to the point where these rays converge, again relevant to converging lenses. Reflection would involve light bouncing off a surface, not the action of a lens. Thus, a divergent lens effectively produces divergence of parallel light rays, supporting the understanding of how optical devices manipulate light in various ways.