Fourier transform interferometer

A high-resolution fourier-transform interferometer (FTIR) which measures the spectral absorption due to the presence of infrared-active gases across the entire spectral region from 1 to 15 xm. This is interfaced to a multi-pass optical-absorption gas cell, which provides a path length of up to 120 m to enable gas detection with high sensitivity. 

A measurement of the optical conductivity of PAni samples over the range 2 meV to leV is illustrated in Fig. 9.38. The reflection spectra were obtained using a Fourier transform interferometer and a synchrotron radiation source. The Kramers-Kroiiig transformation, with appropriate extrapolation of the data to zero and high energy, was used to extract the complex frequency-dependent conductivity and its real part, the optical conductivity. The optical conductivity is related to the imaginary component of the electric susceptibility, since the power dissipated by an optical field of amplitude E is given by ... 

FTIR spectra were recorded using a Bruker 113V Fourier transform interferometer. Frequencies are accurate to 1 crn k Solid samples were studied as Nujol mulls (Nujol was previously dried on sodium wire and bubbled with argon). Structural parameters and initial force field were taken from literature [3] and the program used to calculate the generalized valence force field was similar to Schachtschneider s one. [4]... 

Ohta, M. Hattori, H. Matsuo, Development of a multi-Fourier-transform interferometer imaging experiments in miUimeter and submiltimeter wave bands. Appl. Opt. 46, 2881-2892 (2007). doi 10.1364/AO.46.002881... 

Considering that/r = vh, where 5 is the spectroscopical optical path difference due to the movable mirror (as in Eq. 2.9), the measurement of the mutual coherence function by a Multi-Fourier Transform Interferometer of the waves obtained by two apertures for a given baseline and measuring a specific source intensity I 9, n) is... 

K. Strong, T. J. Johnson, G.W. Harris, Visible intracavity laser spectroscopy with a step-scan Fourier-transform interferometer. Appl. Opt. 36, 8533 (1997)... 

Figure 13 Block diagram of a CD spectrometer with a periodic variation of the state of polarization and by this an intensity modulation by the absorption cfifference of the sample for the UV/vis (a) and the IR (b) spectral region if the optical dements are suitable chosen (S = source of radiation M/F = monochromator (a, b), or Fourier transform interferometer (b) P = polarizer PEM = photo-toelastic modulator C = sample cell PM = photomultiplier (a, b) or another detector (b) EL-R=electronic equipment/computer/re-corder).

The use of infrared spectroscopy for the characterization of polymer blends is extensive (Olabisi et al. 1979 Coleman and Painter 1984 Utracki 1989 He et al. 2004 and references therein Coleman et al. 1991, 2006). The applicability, fundamental aspects, as well as principles of experimentation using infrared dispersive double-beam spectrophotometer (IR) or computerized Fourier transform interferometers (FTIR) were well described (e.g., Klopffer 1984). 

The basic measurement layout is illustrated in Figure 2. Here radiation from an IR source is dispersed either by a diffraction grating or a Fourier-transform interferometer so that different wavelengths of the radiation can be distinguished. An infrared optical filter is placed in the beam to restrict... 

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