  Due to the angular condition in the light-front dynamics (LFD), the
extraction of the electromagnetic form factors for spin-1 particles can be
uniquely determined taking into account implicitly non-valence and/or the
zero-mode contributions to the matrix elements of the electromagnetic current.
No matter which matrix elements of the electromagnetic current is used to
extract the electromagnetic form factors, the same unique result is obtained.
As physical observables, the electromagnetic form factors obtained from matrix
elements of the current in LFD must be equal to those obtained in the instant
form calculations. Recently, the Babar collaboration \cite{Aubert2008} has
analyzed the reaction $e^+ e^-\rightarrow \rho^+ + \rho^-$ at $\sqrt{s}=10.58
GeV$ to measure the cross section as well as the ratios of the helicity
amplitudes $F_{\lambda'\lambda}$. We present our recent analysis of the Babar
data for the rho meson considering the angular condition in LFD to put a
stringent test on the onset of asymptotic perturbative QCD and predict the
energy regime where the subleading contributions are still considerable.
