Direct imaging of exoplanets

Most of the exoplanets known today have been discovered by indirect
techniques, based on the study of the host star radial velocity or
photometric temporal variations. The planet populations explored are
in the first 5-8 AU from the central stars, and have provided precious
information on the way planet form and evolve at such separations.
Direct imaging on 8-10 meter-class telescopes allows detection of
giant planets at larger separations (currently typically > 5-10 AU),
complementing thus indirect techniques.  So far, each of the -yet very
few- giant planets imaged provides an opportunity of unique dedicated
studies of their orbital, physical and atmospheric properties and
sometimes also on their interaction with "second generation", debris
disks. Actually, these few detections already challenge formation
theories.

I will present the results of direct imaging surveys obtained so far,
what they already tell us about giant planet formation and
evolution. Individual and emblematic cases will be detailed; they
illustrate what future instruments will routinely deliver for a much
larger number of stars. I will also point out the limitations of
direct imaging as well as the needs for further work in terms of
planet formation modelling.  I will finally present the tremendous
progress expected in this field thanks to forthcoming planet imagers
on 8-10 meter class telescopes, and on Extremely Large optical
Telescopes.