  Reconstruction of light profiles with amplitude and phase information, called
holography, is an attractive optical technique to display three-dimensional
images. Due to essential requirements for an ideal hologram, subwavelength
control of both amplitude and phase is crucial. Nevertheless, traditional
holographic devices have suffered from their limited capabilities of incomplete
modulation in both amplitude and phase of visible light. Here, we propose a
novel metasurface that is capable of completely controlling both amplitude and
phase profiles of visible light independently with subwavelength spatial
resolution. The simultaneous, continuous, and broadband control of amplitude
and phase is achieved by using X-shaped meta-atoms based on expanded concept of
the Pancharatnam-Berry phase. The first experimental demonstrations of complete
complex-amplitude holograms with subwavelength definition are achieved and show
excellent performances with remarkable signal-to-noise ratio compared to
traditional phase-only holograms. Extraordinary control capability with
versatile advantages of our metasurface paves a way to an ideal holography,
which is expected to be a significant advance in the field of optical
holography and metasurfaces.
