Patent ID: 6229614
Filing Date: 2001-05-08
Classification: G01J

Abstract:
A method of recording a Fourier transform of a spectrum of a medium or fluid by use of an interferometer having at least three optical devices including a beamsplitter and two retroreflectors arranged to form a Fourier transform spectrometer, and wherein a first light beam is split into two separate beams by a beamsplitter, and wherein the two separate beams pass through two separate paths including reflecting devices and meet in the beamsplitter mutually interfering and forming a second light beam, and wherein said second light beam passes through a portion of the medium or fluid, and wherein the second light beam is detected by a detecting device after having passed through the medium or fluid, said method comprising:moving the beamsplitter during the recording of the Fourier transform of the spectrum of the medium or fluid while the retroreflectors stay fixed.