  Control over optical spatial coherence is a key requirement in diverse
applications including imaging, optical trapping, and communications. Current
approaches to controlling spatial coherence are constrained by speed or limited
to a single pair of optical fields. Here, we propose a method to achieve
single-shot control of the spatial coherence between an arbitrary number of
fields. Our method employs a multi-port linear optical device, which we realize
by shaping the wavefront of the input light fields and transmitting them
through a complex medium. To demonstrate the capabilities of our method, we
experimentally realize a 3x3-port system and use it to generate three output
beams with desired mutual correlations.
