Basic Tools and Technical Challenges
Interferometric imaging requires detection of very faint signals and reproduction of interferometric visibilities to high precision; the time resolution of the detectors should reach 1 ms. Developing such an interferometer using Michelson technique is very challenging, which is linked with the advancement of required technology in the areas of opto-mechanics, opto-electronics, and computing. Apart from the design and construction of such an instrument, the physical stability, equalization of pathlength, fringe-tracking, vibration control, adaptive optics, dispersion, and calibration problems are necessary to look into. As stated earlier (see Sect. 5.1) the fringes can be obtained if the optical path difference (OPD) between the light from a stellar source through the two telescopes to the point of interference is smaller than the coherence length, ≤lc. Over an extended field-of-view(FOV), this OPD needs to be continuously measured and corrected before the beam combination takes place. The contrast of the fringes tones down due to:
KeywordsModulation Transfer Function Fringe Pattern Basic Tool Atmospheric Turbulence Chromatic Dispersion
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