Method for observing an emission of light from a sample in a medium of refractive index nL disposed against a surface of a transparent support of refractive index nS, greater than nL, the emission of light comprising luminous components oriented toward the support and forming an angle θ and including supercritical luminous components and critical or subcritical luminous components, implementing an observation device applying filters to the signal; and transforming the signal into an image zone of the sample Modulation of the signal is carried out, in which components of the emission of light are allowed to pass through so as to obtain image zones, the modulation pertaining to all or some of the collected signals; and at least one useful image zone of the sample is produced by combining image zones, the combination evidencing differences between the image zones related to the modulation.