High-resolution interferometers

One of the main design problems in an FTIR spectrometer is to obtain accurate, uniform translation of Mj over distances 6 which may be as large as 1 m in a high-resolution interferometer. 

Satellite-based high-resolution interferometers and radiometers... 

Figure 5.18. Cat s-eye interferometer employed in many early high-resolution interferometers made by Connes and other French spectroscopists. (Reproduced from [3].)...

Figure 9 Layout of the Turku high-resolution interferometer.

Rawlins, W. T. (1983). Rocketbome cryogenic (10 K) high-resolution interferometer spectrometer flight HIRIS auroral and atmospheric IR emission spectra. Applied Optics, 22,1056-69. 

One of the main advantages of the optical-based sensors is their high resolution. Integrated optical sensors16, especially the interferometric ones that have been developed in recent years, such as the Mach-Zehnder interferometer (MZI)17 and the Young interferometer 18-21, show an extremely high refractive index resolution in the range of 10 1—10 8 RIU (refractive index units)17,21, which is equivalent to... 

Using a high-resolution spectrograph and a Fabry-Perrot interferometer, Gunther eta/. 727) resolved a number of equidistant components with a mean separation of 0.04 cm" in the stimulated Raman spectrum of CSj, which can be attributed to resonant modes in single medium-scale filaments of self-trapped radiation within the liquid. 

Howard has applied his method to high-resolution infrared spectroscopic data obtained by dispersive techniques and to both experimental and simulated Fourier interferograms. The method in the latter application explicitly renders the data as they would be observed by an interferometer having a path difference exceeding the mechanical limits of the instrument used for the observation. Details on both the method and its application constitute Chapters 9 and 10. 

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. 

SMA Submillimeter Array, large interferometer array operating on the top of Mauna Kea, Hawaii, operating at the millimeter wavelength range that allows high-resolution studies of protostellar environments. 

Interferometers can easily be adapted to the required resolution. One interferometer may either provide the very high resolution needed for a analysis of gas spectra, or a high optical conductance at a lower resolution, which is ideal for quick and reliable routine analysis. Their simple, rugged construction make interferometers suitable even for the industrial environment, where they serve in production and quality control. Due to the development of modern micro electronics, the necessary Fourier transformation can now be performed in real time by micro processors, together with the other procedures needed to evaluate the spectra for analytical purposes. 

High resolution gas pressure measurements based on the evaluation of the refractive index can be performed with a Michelson-interferometer ... 

We have performed optically heterodyne-detected optical Kerr effect measurement for transparent liquids with ultrashort light pulses. In addition, the depolarized low-frequency light scattering measurement has been performed by means of a double monochromator and a high-resolution Sandercock-type tandem Fabry-Perot interferometer. The frequency response functions obtained from the both data have been directly compared. They agree perfectly for a wide frequency range. This result is the first experimental evidence for the equivalence between the time- and frequency-domain measurements. 

The depolarized low-frequency LS measurement is performed under stationary excitation by means of a double monochromator for a wide frequency range and a Sandercock-type tandem Fabry-Perot interferometer for a high-resolution study. The same samples as above are measured using 1 cm glass cell. The LS is measured under a depolarized condition in a right-angled configuration. 

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