Photothermal interference spectrometer for measuring electromagnetic radiation absorption - has heating beam, passing through heated medium and interfering with direct beam

摘要

The photothermal interference spectrometer has one beam (1) which heats a medium by absorption, one (2) which passes through the heated medium and one (3) which is not passed through the medium but is brought into interference with the one which is passed through. The interfering beams pass through a two-beam interferometer or the second beam passes through a multibeam interferometer. The heating beam can be modulated. It can be pulsed and can be absorbed by a solid body in thermal contact with the medium. USE/ADVANTAGE - For direct, contactless evaluation of absorption of electromagnetic radiation by medium with reduced sensitivity to mechanical vibrations and thermal fluctuations.