  Gravitational weak shear produced by large-scale structures of the universe
induces a correlated ellipticity distribution of distant galaxies. The
amplitude and evolution with angular scale of the signal depend on cosmological
models and can be inverted in order to constrain the power spectrum and the
cosmological parameters. We present our recent analysis of 50 uncorrelated VLT
fields and the very first constrains on ($\Omega_m,\sigma_8$) and the nature of
primordial fluctuations based on the join analysis of present-day cosmic shear
surveys.
