All Figures

$\begin{figure} \par\rotatebox{360} {\resizebox{14cm}{9cm}{\includegraphics[clip]{0270fig1.ps}}}\end{figure}$ Figure 1: Description of the algorithm. The example uses a triple aperture for a simplified ("honeycomb-like'') 3-dimensional structure of dispersed speckles. Clockwise from top-left: A- aperture ; B- its Fourier transform, in intensity form, which is the recorded star image, in blue light. C- layering of a blue and red image, before re-scaling; D- input cube with all wavelength layers, re-scaled. With 3 apertures, it is a honeycomb pattern, tilted in response to the piston values. With more apertures, it has 3-dimensional speckles. E- output cube, calculated as a 3-dimensional Fourier transform of D. Its active columns contain "signal dots'' at heights proportional to the piston value in the corresponding baseline. The six dots here obtained with 3 apertures are in a plane tilted like the piston value map.
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In the text

$\begin{figure} \par\rotatebox{360} {\resizebox{7cm}{6cm}{\includegraphics[clip]{0270fig2.ps}}}\end{figure}$ Figure 2: Statistical reconstruction of piston values from the output cube, here shown in the case of a 5-aperture circle. N subsets from the set of output columns (only 3 of 5 are shown here), each related to a given "starting'' aperture, are extracted from the cube and repositioned so that identical "target'' apertures (indicated by arrows in the sketches at right) are aligned vertically in separate layers. The set of signal dots in each layer is, in principle, globally translated vertically according to the piston value of the "starting'' aperture. This error can be determined by intercorrelating the layers, using a multiple correlation of order (N-1) applied to the vertical translations along the columns.
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In the text

$\begin{figure} \par\resizebox{7cm}{6cm}{\includegraphics[clip]{0270fig3.ps}}\par\resizebox{7cm}{6cm}{\includegraphics[clip]{0270fig3_bis.ps}}\end{figure}$ Figure 3: Intensity along one active column with no noise (solid lines) and with one realization of photon noise (dotted lines) Top: with 320 photons per cube for six apertures arranged as shown. Bottom: with 1600 photons per cube for ten apertures arranged as shown.
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In the text

$\begin{figure} \par\rotatebox{270}{\resizebox{6cm}{8.8cm}{\includegraphics[clip]{0270fig4.ps}}}\end{figure}$ Figure 4: Contrast of the signal dots with 3 to 10 apertures. Curves with line points show simulations with, from top to bottom, 6400 photons, 3200 photons, 1600 photons, 960 photons and 640 photons per cube. From top right to bottom, curves without line points are based on theory, showing cases with 6400 photons, 3200 photons, 1600 photons and 960 photons per cube.
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In the text

$\begin{figure} \par\rotatebox{270}{\resizebox{6cm}{8.8cm}{\includegraphics[clip]{0270fig5.ps}} }\end{figure}$ Figure 5: From top to bottom: evolution of the number of photon needed in order to do coronagraphy, imaging and recover signal from noise with 3 to 10 apertures.
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In the text

$\begin{figure} \par\rotatebox{270} {\resizebox{6cm}{8.8cm}{\includegraphics[clip]{0270fig6.ps}}}\end{figure}$ Figure 6: From top to bottom: evolution of the limiting stellar magnitudes for coronagraphy, for imaging and for minimal signal detection, with 3 to 10 apertures. Solid curves correspond to interferometers with a constant collecting area of 150 m² and dotted lines to a constant 8 m-aperture size. Exposures last 0.02 s and the global quantum efficiency is 10%.
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In the text

$\begin{figure} \par\resizebox{7cm}{6cm}{\includegraphics[clip]{0270fig3.ps}}\par\resizebox{7cm}{6cm}{\includegraphics[clip]{0270fig3_bis.ps}}\end{figure}$	Figure 3: Intensity along one active column with no noise (solid lines) and with one realization of photon noise (dotted lines) Top: with 320 photons per cube for six apertures arranged as shown. Bottom: with 1600 photons per cube for ten apertures arranged as shown.
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$\begin{figure} \par\rotatebox{270}{\resizebox{6cm}{8.8cm}{\includegraphics[clip]{0270fig4.ps}}}\end{figure}$	Figure 4: Contrast of the signal dots with 3 to 10 apertures. Curves with line points show simulations with, from top to bottom, 6400 photons, 3200 photons, 1600 photons, 960 photons and 640 photons per cube. From top right to bottom, curves without line points are based on theory, showing cases with 6400 photons, 3200 photons, 1600 photons and 960 photons per cube.
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$\begin{figure} \par\rotatebox{270}{\resizebox{6cm}{8.8cm}{\includegraphics[clip]{0270fig5.ps}} }\end{figure}$	Figure 5: From top to bottom: evolution of the number of photon needed in order to do coronagraphy, imaging and recover signal from noise with 3 to 10 apertures.
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$\begin{figure} \par\rotatebox{270} {\resizebox{6cm}{8.8cm}{\includegraphics[clip]{0270fig6.ps}}}\end{figure}$	Figure 6: From top to bottom: evolution of the limiting stellar magnitudes for coronagraphy, for imaging and for minimal signal detection, with 3 to 10 apertures. Solid curves correspond to interferometers with a constant collecting area of 150 m² and dotted lines to a constant 8 m-aperture size. Exposures last 0.02 s and the global quantum efficiency is 10%.
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