- The document discusses Fourier transform infrared (FTIR) spectroscopy, including the basic theory and components of an FTIR spectrometer. - An FTIR spectrometer uses an interferometer to simultaneously collect infrared spectral data over a wide spectral range, which is then converted to a spectrum through Fourier transformation. - Key components include a source, beamsplitter, moving mirror, fixed mirror, and detector. Various accessories allow analysis of solids, liquids, and gases. Applications include pharmaceutical analysis, polymer characterization, and quality control.