SECOND GENERATION INSTRUMENTATION FOR THE VLTI: THE FRENCH VLTI CONNECTION DENIS MOURARD 1 , OLIVIER LARDIERE 2 , BRUNO LOPEZ 1 , FABIEN MALBET 3 and PHILIPPE STEE 1 1 Observatoire de la Côte d’Azur 2 Observatoire de Haute Provence 3 Laboratoire d’Astrophysique de l’Observatoire de Grenoble, France E-mail: mourard@obs-azur.fr Abstract. We describe the current French ideas for the instrumentation of the second generation of the VLTI. Instruments concepts addressed include: integrated optics beam combiner, extension of MIDI to a four beam facility, extension of AMBER to the visible and a densified pupil direct imaging beam combiner. Keywords: VLTI, instrumentation 1. Introduction After more than ten years of development, the European optical long baseline inter- ferometer (the VLTI) is gradually reaching its full performances with the scheduled commissioning in 2003 of a large number of main subsystems: focal instrument MIDI for the 10 μm band, focal instrument AMBER for the near infrared and the three telescopes mode, adaptive optic devices MACAO for the UTs, fringe sensor unit FINITO. As such, the VLTI will become one of the very first interferometric facility in the world. A very high quality and quantity of astrophysical results could be cer- tainly expected in the coming years. New extensions are soon foreseen like a dual field facility (PRIMA) that would allow astrometric measurements with a spatial resolution of the order of a few tens of micro arcseconds. This will also allow to increase the limiting magnitude of the first generation focal instruments by the use of the technique of the phase reference imaging. Also, a demonstrator of nulling interferometry (GENIE) is under study in the framework of a collaboration with the European Space Agency concerning the preparation of the Darwin mission. During the June 2001 workshop about the second generation of instruments for the VLT/VLTI, ESO has concluded about two main priorities for the development of the VLTI: an imaging mode with 6 to 8 beams and an extension to the shortest wavelengths (visible band). In both cases, the French community has brought some original ideas that should be discussed in the European astronomical community. Among these, we will describe in more details the following actions: IONIC- Astrophysics and Space Science 286: 291–296, 2003. © 2003 Kluwer Academic Publishers. Printed in the Netherlands.