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Implementation of a Reference Interferometer for Nanodetection
Published on: April 26, 2014
Chromatism compensation in wide-band nulling interferometry for exoplanet detection
Julien Spronck1, Silvania F Pereira, Joseph J M Braat
1Optics Research Group, Department of Applied Sciences, Delft University of Technology, Lorentzweg 1, NL-2628 CJ Delft, The Netherlands. J.Spronck@tnw.tudelft.nl
Applied Optics
|February 21, 2006
Summary
We introduce chromatism compensation for nulling interferometry, achieving high spectral band rejection ratios. This method relaxes the achromaticity condition and is analyzed for three-telescope configurations.
Area of Science:
- Optical Interferometry
- Astronomy
Background:
- Nulling interferometry aims for high contrast imaging by suppressing starlight.
- Traditional nulling interferometers often require strict achromaticity conditions for broadband operation.
Purpose of the Study:
- To introduce and analyze a novel concept of chromatism compensation in nulling interferometry.
- To investigate the implications of this compensation on the achromaticity requirement.
- To explore the applicability of this technique in different interferometer configurations.
Main Methods:
- Theoretical analysis of chromatism compensation in nulling interferometry.
- Investigation of the constraints for applying chromatism compensation to two-beam interferometers.
- Detailed analysis of a three-telescope nulling interferometer configuration.
Main Results:
- Demonstration of chromatism compensation enabling high rejection ratios across a wide spectral band.
- Identification that chromatism compensation cannot be applied to two-beam nulling interferometers.
- Characterization of the performance in a three-telescope setup.
Conclusions:
- Chromatism compensation offers a new approach to enhance broadband performance in nulling interferometry.
- The achromaticity condition can be relaxed, simplifying instrument design.
- The technique shows promise, particularly for multi-telescope configurations like the three-telescope case analyzed.
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