  We experimentally generate three-dimensional speckles with customized
intensity statistics. By modulating the phase front of a laser beam, far-field
speckle patterns maintain the designed intensity probability density function
while evolving to different spatial patterns upon axial propagation. We also
create speckles with distinct intensity statistics at multiple designated
planes. These results open many new possibilities, such as designing volumetric
speckle statistics for three-dimensional imaging, sensing, trapping, and
manipulation.
