Introduction

We are in the case of temporally and spatially coherent sources. A multiple-waves interferometer makes the superposition of a multitude or even an endless number of waves, all out of phase. If the relation phase between all the waves is perfectly deterministed the fringes figure can have remarkable properties. In the case where the relation phase between all the waves is random, the resulting figure is a “speckle”. The speckle will not be discussed in this class.

The case of the deterministed relation phase is studied later in the class when the complex amplitude relationship between the waves is a geometric sequence.