SIMPLE OPTICAL COMPONENTS A. Reflection and Refraction B. Transmission Through Optical Components C. Graded-Index Optical Components INTERFERENCE A. Interference of Two Waves B. Multiple-Wave Interference POLYCHROMATIC LIGHT A. Fourier Decomposition B. Light Beating | Fundamentals of Photonics Bahaa E. A. Saleh Malvin Carl Teich Copyright 1991 John Wiley Sons Inc. ISBNs 0-471-83965-5 Hardback 0-471-2-1374-8 Electronic CHAPTER WAVE OPTICS POSTULATES OF WAVE OPTICS MONOCHROMATIC WAVES A. Complex Representation and the Helmholtz Equation B. Elementary Waves C. Paraxial Waves RELATION BETWEEN WAVE OPTICS AND RAY OPTICS SIMPLE OPTICAL COMPONENTS A. Reflection and Refraction B. Transmission Through Optical Components C. Graded-lndex Optical Components INTERFERENCE A. Interference of Two Waves B. Multiple-Wave Interference POLYCHROMATIC LIGHT A. Fourier Decomposition B. Light Beating Christiaan Huygens 1629-1695 advanced several new concepts concerning the propagation of light waves. Thomas Young 1773-1829 championed the wave theory of light and discovered the principle of optical interference. 41 Light propagates in the form of waves. In free space light waves travel with a constant speed co X 108 m s 30 cm ns or mm ps . The range of optical wavelengths contains three bands ultraviolet 10 to 390 nm visible 390 to 760 nm and infrared 760 nm to 1 mm . The corresponding range of optical frequencies stretches from 3 X 1011 Hz to 3 X 1016 Hz as illustrated in Fig. . The wave theory of light encompasses the ray theory Fig. . Strictly speaking ray optics is the limit of wave optics when the wavelength is infinitesimally short. However the wavelength need not actually be equal to zero for the ray-optics theory to be useful. As long as the light waves propagate through and around objects whose dimensions are much greater than the wavelength the ray theory suffices for describing most phenomena. Because the wavelength of visible light is much shorter than the dimensions of the visible objects encountered in our daily lives manifestations of the wave nature of light are not apparent without careful observation. In this chapter light is described by a scalar function called the wavefunction which obeys .
