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A mid-infrared broadband achromatic astronomical beam combiner for nulling interferometry

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 نشر من قبل John D. Monnier
 تاريخ النشر 2010
  مجال البحث فيزياء
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Integrated optic beam combiners offer many advantages over conventional bulk optic implementations for astronomical imaging. To date, integrated optic beam combiners have only been demonstrated at operating wavelengths below 4 microns. Operation in mid-infrared wavelength region, however, is highly desirable. In this paper, a theoretical design technique based on three coupled waveguides is developed to achieve fully achromatic, broadband, polarization-insensitive, lossless beam combining. This design may make it possible to achieve the very deep broadband nulls needed for exoplanet searching.

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