Wide-Angle Interference of Multipole Radiation

Abstract

The paper presents a discussion of wide-angle interference phenomena and their dependence upon the nature of the light. Formulas are derived representing the interference pattern for various geometrical arrangements and for arbitrarily composed sources. It is shown that the coherence properties of beams emerging from a point source should depend in a marked manner upon the type of poles which compose it. Special discussion is given for dipole, quadrupole, and octopole sources. The treatment is limited to the use of ideal mirrors; extensions are indicated.