IR-PAS Studies: Signal-To-Noise Enhancement and Depth Profile Analysis
The IR-PAS technique is hampered in many instances in its applications by the low signal-to-noise (S/N) ratio, which is generally due to environmental noise present around the equipment. A chamber is described which acoustically isolates the detector, resulting in a S/N ratio enhancement of more than a factor of three. Preliminary studies involving different mirror velocities hint that a phase delay may exist between a given interferometer modulation frequency and the corresponding acoustical wave, a phenomenon which may be applicable to depth profile studies.
KeywordsDepth Profile Phase Delay Attenuate Total Reflectance Environmental Noise Carbonyl Band
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