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Interferometers are widely used imaging instruments in astronomy thanks to their hyperfine angular resolution. With these instruments, the real images can be retrieved by a series of measurements of fringes contrast. The effectiveness of this technique hinges on the theorem of Zernike and Van Cittert which links the angular distribution of an object (and hence its image) to the fringes contrast function one can observe by combining the signals coming from two or more distinct telescopes. We have recently improved this technique by integrating a pair of nonlinear crystal waveguides on either arm of our interferometer, so to apply a parametric process of sum frequency generation. Although our star simulator emits an infrared radiation, the combination of sum frequency generation and interference permit us to measure the fringes contrast at visible light. We believe that this technique can provide a spin-off for technology of astronomical imaging in the far infrared, where detectors are at present time less efficient. Optical interferometers, first and second order coherence analyses are also the key ingredients to explore non classical states of light. We plan to undertake a series of experiments in this field envisaging possible applications in quantum key distribution.
tWe have proposed a new kind of instrument able to provide a direct image with a telescope array. This versatile concept can be easily modified to fit the astronomical requirements such as the detection of exoplanet. Thanks to our skill in the fibre use for high resolution imaging in astronomy we have implemented a temporal hypertelescope in order to valid this new concept. The optimisation of the experimental configuration is under progress and first results have demonstrated a dynamic close to 500 and the possibility to image a binary star.