First experimental realization of six-pack holography and its application to dynamic synthetic aperture superresolution

It has long been assumed that off-axis holography is less spatial bandwidth efficient than on-axis holography. Six-pack holography (6PH) is the first off-axis configuration that changes this paradigm. We present the first experimental realization of 6PH, an off-axis interferometric system capable of spatially multiplexing six complex wavefronts while using the same number of camera pixels needed for a single off-axis hologram. Each of the six parallel complex wavefronts is encoded using a different fringe orientation and can be fully reconstructed. This technique is especially useful for dynamic samples, as it allows the acquisition of six complex wavefronts simultaneously. There are many applications for the data that can be compressed into the six channels. Here, we utilize 6PH to increase resolution in dynamic synthetic aperture imaging, where each of the six optically compressed off-axis holograms encodes a different spatial frequency range of the imaged sample, yielding 1.62× resolution enhancement.