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Real-time distance measurement immune from atmospheric parameters using optical frequency combs

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 نشر من قبل Nicolas Treps
 تاريخ النشر 2012
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Pu Jian




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We propose a direct and real-time ranging scheme using an optical frequency combs, able to compensate optically for index of refraction variations due to atmospheric parameters. This scheme could be useful for applications requiring stringent precision over a long distance in air, a situation where dispersion becomes the main limitation. The key ingredient is the use of a mode-locked laser as a precise source for multi-wavelength interferometry in a homodyne detection scheme. By shaping temporally the local oscillator, one can directly access the desired parameter (distance) while being insensitive to fluctuations induced by parameters of the environment such as pressure, temperature, humidity and CO$_2$ content.



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