INTERFEROMETER FOR FOURIER TRANSFORM INFRARED SPECTROMETRY

摘要

An interferometer wherein an incident beam from a radiation source hits a beam splitter and is split into a first, reflected partial beam, and a second, transmitted partial beam, that subsequently travel along separate arms of the interferometer. The first and second partial beams are respectively intercepted, reflected, and re-split to form returning beam portions and reflected and transmitted exit beam portions that are recombined to form an exit beam. A second terminal mirror and a folding mirror are associated with the second interferometer arm, and the folding mirror reflects the second partial beam back to the beam splitter along the same path through which it was received. The folding mirror and the second terminal mirror are positioned so that a section of the second partial beam passing back-and-forth between the folding mirror and the terminal mirror crosses the exit beam twice.