Infrared Spectroscopy using a Photoacoustic Cell

Photoacoustic spectroscopy is a technique useful for the study of solid and liquid samples when the samples are difficult to analyze by conventional infrared techniques, such as compressed KBr pellets, diffuse reflectance and attenuated total reflectance. A photoacoustic cell designed by Blank and Wakefield [1] and shown in Figure 1 is described. The magnitude of the signal in the photoacoustic cell is proportional to the amount of photon flux emanating from the sample. Therefore, a close correspondence exists between the strength of the acoustic signal and the amount of light absorbed by the sample. The photoacoustic cell has been used as an accessory with both a constant and variable mirror scan Michelson interferometer.