Photoacoustic Spectroscopy and Its Applications – A Tutorial Review

Abstract

Based on photoacoustic effect, photoacoustic spectroscopy is an unusual form of spectroscopy
which uses both light and sound and is based on the absorption of electromagnetic radiation
by analyte molecule. The absorbed energy is measured by detecting pressure fluctuations in
the form of sound waves or shock pulses. A photoacoustic spectrum consists of a plot of the
intensity of the acoustic signal detected by a microphone or a piezoelectric detector, against
the excitation wavelength or another quantity related to the photon energy of the modulated
excitation. It is a valuable source for data acquisition relating to absorption and material
science studies.