Reflection

The first property of light we consider is reflection from a surface, such as that of a mirror. This is illustrated in Fig. 22.5.

  

Figure 22.5: Law of reflection

When light is reflected off any surface, the angle of incidence $\theta_{1}^{}$ is always equal to the angle of reflection $\theta_{2}^{}$ .

Note:

• The angles are always measured with respect to the normal to the surface.
• The law of reflection is also consistent with the particle picture of light.