Fizeau fringes

The external geometric differential delay (see below) of an off axis source is exactly balanced within a Fizeau interferometer, resulting in fringes with the same phase on top of each source in the field. The position of a source may differ from the position of zero OPD in a Michelson interferometer depending on how dissimilar entrance and exit pupils are. The fringe contrast of off-axis sources also depend on the temporal degree of coherence of the detected light. 

The two nearly plane-parallel surfaces of the film constitute a Fizeau interferometer which produces interference fringes in the reflected light [40]. The fringes are lines of constant film thickness. Film drainage data were acquired by generating monochromatic light by means of an interference filter (k= 505 nm) or with a FieNe laser X= 632.8 nm). 

Figure 476 Densitometer trace of the fringe pattern in a Fizeau wavemeter [185]...

Fizeau interference fringes 130 flavellagic acid, heterocyclic cores 722 flexoelectricity... 

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