2. Three examples of interferometric systems

Commercial interferometers are usually composed of :

• a laser source with integrated photodetectors;

• an electronic box (or microcomputer) containing the counting card and a microprocessor capable of making corrections;

• a meteorological station called "automatic compensation" comprising air temperature probes, a pressure probe, sometimes a hygrometry probe and material temperature probes for expansion correction;

• optics (cube corner, separator, etc.).

In the case of displacement measurement, mirrors are replaced by cube corners, which have the particularly interesting property of always reflecting the beam parallel to itself.

• Methods for correcting variations...