Single beam computational 3D microscopy

Three dimensional microscopy allows the reconstruction of both phase and amplitude of the object wavefronts. This in turn sheds information on the optical path length profile of the object. Conventionally 3D microscopy is achieved using two beam interference techniques, which requires adjustment of the beam for high quality interference fringes as well as is more prone to external vibrations. Here we discuss a single beam 3D microscopic technique. The technique works by sampling the volume speckle field generated by putting a diffuser in the path of the probe beam passing through the object at several axial planes and computing the complex amplitude of the object wavefront using angular spectrum approach towards scalar diffraction theory.