ICP atomic emission Fourier transform spectrometers

The Fourier transform spectrometer is based on the interferometer introduced in 1881 by Michelson. The basic configuration of the Michelson 

The interferogram is a Fourier-cosine transform of the spectrum. The desired spectrum is obtained from the interferogram by complex calculations involving an inverse Fourier transformation of the interferogram. 

An ICP FT spectrometer has three optical inputs incorporated into a single optical axis a He-Ne laser, a white light source (tungsten lamp), and an ICP source. The laser controls the digitization sequence and measures the exact location of the moving mirror. 

The main advantages of the Fourier transform spectrometer over conventional dispersive spectrometers are (i) higher energy throughput, because no slits are required, (ii) higher optical resolution, and (iii) ability for simultaneous monitoring of all spectral information for an extended period. 

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