Methode d'excitation du spectre Raman d'une couche mince utilisant un reseau a grand nombre de traits

The Raman spectrum of a dielectric substance deposited in a few microns thick film on a diffraction grating (aluminium coating), is obtained with a trapped laser beam inside the film. In order to assure the most efficient coupling, a single mode of propagation is excited in “reverse coupling”; the selection of groove spacing is discussed.