Sean A. Smith

GRATING LIGHT REFLECTION SPECTROSCOPY

R ecent advances in holographic techniques for fabricating high-quality diffraction gratings on dielectric substrates have stimulated their use for spectroscopic studies of surfaces and properties of media in contact with the gratingcovered interface. There are a number of examples in which surface gratings with periods on the order of visible light wavelengths have served as a coupler between light waves and surface plasmons and polaritons. Also, Sainov and co-worker, using a relatively old idea ® rst proposed by Rytov and Fabelynskii, constructed a binary metal grating device on glass, working in total internal re ̄ ection mode, as a sensor for the determination of absorbance in liquid samples. We have developed a new optical diagnostic method, grating light rē ection spectroscopy (GLRS), based on measurements near critical points of intensity and phase in waves rē ected from a transmission diffraction grating in contact with a diagnostic sample. The theory and experimental studies of the method are described in three previous articles