  Wavefront cleaning by single-mode fibers has proved to be efficient in
optical-infrared interferometry to improve calibration quality. For instance,
the FLUOR instrument has demonstrated the capability of fluoride glass
single-mode fibers in this respect in the K and L bands. New interferometric
instruments developped for the mid-infrared require the same capability for the
8-12 um range. We have initiated a program to develop single-mode fibers in the
prospect of the VLTI mid-infrared instrument MIDI and of the ESA/DARWIN and
NASA/TPF missions that require excellent wavefront quality. In order to
characterize the performances of chalcogenide fibers we are developping, we
have set up an experiment to measure the far-field pattern radiated at 10 um.
In this paper, we report the first and promising results obtained with this new
component.
