Abstract

Thirty years have now elapsed since the appearance of Wolf’s classic paper¹; he introduced the concept of the mutual coherence function and showed that the components obeyed rigorous propagation laws. Wolf also noted their relation to the Stokes parameters. The Stokes parameters were originally introduced to describe the interference laws of Fresnel and Arago and, in particular, to provide a mathematical description of unpolarized light. In this paper we show that the Stokes parameters arise naturally in classical optics when the transformation from the nonobserved amplitude formulation to the observed intensity formulation is made. As a result this formulation shows that it is unnecessary to introduce quantum mechanical concepts or even operational definitions to describe them. After this we represent the Stokes parameters in the form of column matrices and then apply this formalism to the description of radiating systems such as the classical Zeeman effect, synchrotron radiation, and quantum dipole radiation.² By introducing the principle of incoherent spectral decomposition we show that the Stokes vectors correspond exactly to the observed spectral lines and they contain all the information available in classical optics which is frequency, intensity, and polarization.

© 1985 Optical Society of America