New Sampling Method in Fourier Spectroscopy

In the continuous drive method of Fourier spectrometer, the movable mirror should be driven at a constant speed. Otherwise the speed fluctuation causes spurious spectrum as ghost in a conventional spectrometer because of the lack of the uniform sampling path difference due to the characteristics of the electric filter. This paper gives a sampling method for correcting the distorted spectrum by the use of electric filter characterized by a flat attenuation and linear phase shift for the main signal, and the delay circuit for the sampling signal. The method is discussed theoretically. Experimental results show that the method is effective to correct the distorted spectrum.