Optical Imaging Using Orbital Angular Momentum: Interferometry, Holography and Microscopy

Light with helical phase wavefront carries orbital angular momentum, a unique feature widening the horizon of optical imaging applicability. Here, we take particular interest in the common but important imaging techniques of interferometry, holography and microscopy using orbital angular momentum of light. In contrast to the conventional imaging techniques that rely on the plane-wave or fundamental Gaussian beam, the orbital angular momentum of light introduces a new physical dimension into the play to enrich the applicable imaging mechanism. Indeed, we revisit the milestone achievements that exploit the orbital angular momentum of light as the essential roles of the interference reference, multiplexing channel, spatial-filter, or excitation source. These methods bestow the imaging applications with many new and various benefits.