ABSTRACT
Spectrometry and spectrophotometry are two important subfields that are part of the larger field of optical metrology. Spectrometry mainly utilizes dispersive-based instrumentation that can be based on prismatic configurations, diffraction grating configurations, or a combination of these. The principal exercise here is to obtain a record of intensity versus wavelength of the material of interest, which provides a unique signature for the atomic or molecular structure of the medium under examination. If a tunable, or broadband, light source illuminates a material sample in the transmission mode, as illustrated in Figure 12.1, then a wavelength scan of the spectrometer yields a record of the absorption spectrum. Alternatively, as illustrated in Figure 12.2, a laser-excited atomic or molecular medium can be used to yield a fluorescence spectrum and an emission spectrum.
