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arXiv · 1407.2719

Cheapest nuller in the world: Crossed beamsplitter cubes

F. Henault·A. Spang
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Abstract

In this communication is described a new type of Achromatic phase shifter (APS) suitable for both nulling interferometry and coronagraphy, based on a couple of crossed beamsplitter cubes, well-suited for equipping future spaceborne instruments searching for extra-solar planets located in a habitable zone. We present the general principle of this APS and discuss possible implementations into a nulling coronagraph telescope or into a sparse-aperture interferometer, either of the Fizeau or Michelson type. Expected performance in terms of transmission maps and a preliminary tolerance analysis are also provided. It turns out that the device is cheap, compact, and presents reasonable manufacturing tolerances and costs

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F. Henault, A. Spang. 2014-07-10. Cheapest nuller in the world: Crossed beamsplitter cubes. https://doi.org/10.1117/12.2055091

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