Applied Electro-Optics

9 Quanta and Optical Spectra

9.1 The Dual Nature of Light–Particles and Waves

In the first few chapters, we studied the various properties of light such as propagation, reflection, refraction, interference, diffraction, and polarization. These topics concentrated on the wave nature of light. All of these phenomena can be explained using classical physics. In this chapter, we will begin our study of the production of light by studying the basic structure of matter. As discussed in Chapter 3, Maxwell’s equations treat the propagation of light, whereas the quantum theory describes the interaction of radiation and matter. The electron plays an important role in this interaction. A combined theory called quantum electrodynamics best describes the ...