34.1.2 Ray Diagrams

Rays originate from every point on an object and travel outward in all directions, but a diagram trying to show all these rays would be hopelessly messy and confusing. To simplify the picture, we usually use a ray diagram showing only a few rays. For example, FIGURE 34.4 is a ray diagram showing only a few rays leaving the top and bottom points of the object and traveling to the right. These rays will be sufficient to show us how the object is imaged by lenses or mirrors.

FIGURE 34.4 A ray diagram simplifies the situation by showing only a few rays.

The figure illustrates few of the infinite rays leaving a tree.
FIGURE 34.4 Full Alternative Text

NOTE   Ray diagrams are the basis for a pictorial representation that we’ll use throughout this chapter. Be careful not to think that a ray diagram shows all of the rays. The rays shown on the diagram are just a subset of the infinitely many rays leaving the object.