  We extend the recently developed formalism to extract light-front quark
charge densities from nucleon form factor data to the deformations of these
quark charge densities when applying an external electric field. We show that
the resulting induced polarizations can be extracted from proton generalized
polarizabilities. The available data for the generalized electric
polarizabilitiy of the proton yield a pronounced structure in its induced
polarization at large transverse distances, which will be pinned down by
forthcoming high precision virtual Compton scattering experiments.
