Theoretical Evaluation of a Wide-Angle Interference Experiment

Abstract

Two previously published investigations of the wide-angle interference of multipole radiation and the theory of Lloyd's mirror are continued. The formulas are extended to cover the cases of total internal reflection and observation made through a single Nicol prism. The theoretical basis is thus obtained for the evaluation of a wide-angle interference experiment carried out by Selényi with light from a thin fluorescent layer. Comparison of this theory with his observations made with a Nicol prism shows that the source can be composed only of electric dipoles or magnetic quadrupoles. The possibility of the latter can be excluded either by general physical reasoning, or by comparison of our theory with his observations made at various angles of divergence without the Nicol prism. It may thus be said that the source of fluorescence light has been shown to consist of electric dipoles.