Anticaustics in a Fabry-Perot interferometer

TL;DR

This paper investigates the geometrical behavior of wavefronts in a Fabry-Perot interferometer, revealing that anticaustics form ellipsoids or hyperboloids, offering new insights into its operation and comparison with other optical systems.

Contribution

It introduces a geometric interpretation of anticaustics in a Fabry-Perot interferometer, linking wavefront behavior to familiar optical arrangements.

Findings

Anticaustics form ellipsoids or hyperboloids of revolution.

Provides a geometric framework for understanding Fabry-Perot operation.

Facilitates comparison with other optical systems like Young's double slit.

Abstract

We address the response of a Fabry-Perot interferometer to a monochromatic point source. We calculate the anticaustics (that is, the virtual wavefronts of null path difference) resulting from the successive internal reflections occurring in the system. They turn to be a family of ellipsoids (or hyperboloids) of revolution, which allows us to reinterpret the operation of the Fabry-Perot from a geometrical point of view that facilitates comparison with other apparently disparate arrangements, such as Young's double slit.