Systems and methods for azimuthal multiplexing using three-dimensional diffractive optics An azimuthal optical multiplexing system includes a light source. The system includes two or more at least partially transparent plates. Each plate of the two or more plates has a structured or patterned surface positioned in an optical path of the light source. The system includes means for rotating at least one plate of the two or more plates axially with respect to at least one other plate of the two or more plates. The means for rotating is operatively coupled to the at least one plate. The structured or patterned surface is configured to modulate light directed along the optical path and through the two or more plates.