  The full-dimensional spatial light meta-modulator requires simultaneous,
arbitrary and independent manipulation of spatial phase, amplitude, and
polarization. It is an essential step towards harnessing complete dimensional
resources of light. However, full-dimensional meta-modulation can be
challenging due to the need of multiple independent control factors. To address
this challenge, here we propose parallel-tasking geometric phase metasurfaces.
Indeed, the broadband geometric phase of meta-atoms is divided into several
sub-phases, each of which serves as an independent control factor to manipulate
light phase, amplitude, and polarization through geometric phase, interference,
and orthogonal polarization beam superposition, respectively. Therefore, the
macroscopic group of meta-atoms leads to the metasurfaces that can achieve the
broadband full-dimensional spatial light meta-modulation. Finally, we fabricate
and experimentally demonstrate the meta-modulator that generates special
structured light beams with original or modified diffractions, as the signature
of spatial phase, amplitude and polarization modulation. This approach paves
the way to future wide applications of light manipulation enabled by the
full-dimensional spatial light meta-modulators.
