Fabry-Perot's interference spectrometer (1961)

The Fabry-Perot interference spectrometer, made up of two semi-reflective, flat and parallel beam splitters with high reflection coefficients, allows the spectrum of light to be obtained from interference. It would be used, in particular, for the separation of very close wavelengths, the creation of highly selective interference filters and laser cavities, and the control of telecommunication signal wavelength.