Peri-critical reflection spectroscopy devices, systems, and methods

摘要

An apparatus comprises an electromagnetic radiation source adapted to excite a sample with electromagnetic radiation in at least a first wavelength and a second wavelength, and a crystal having a refractive index higher than that of the sample and adapted to reflect the electromagnetic radiation in the at least first wavelength and second wavelength. A reflector is adapted to introduce the electromagnetic radiation in the at least first wavelength and second wavelength to the sample at a location at a plurality of angles of incidence encompassing a critical angle between the crystal and the sample. A detector is provided for detecting a return electromagnetic radiation from each of the at least first wavelength and second wavelength from the sample at the plurality of angles of incidence with millidegree resolution so that it is possible to identify intensity of reflected electromagnetic radiation at angles proximate to the critical angle.