  We have studied in perturbative QCD all independent helicity amplitudes
describing the photoproduction of light vector mesons at large $t$. We found a
new hard production mechanism which is related to the possibility for a real
photon to fluctuate into a massless $q\bar q$ pair in a chiral-odd spin
configuration. Each helicity amplitude is given as a sum of chiral-even
contribution (when the helicities of quark and antiquark are antiparallel) and
this additional chiral-odd part (where the helicities of quark and antiquark
are parallel). The chiral-odd contribution is large, it leads to a dominance of
the non spin-flip amplitude in a very broad region of intermediately high
$|t|$.}
