Synthetic-aperture experiment in the visible with on-axis digital heterodyne holography

We have developed a new on-axis digital holographic technique, heterodyne holography. The resolution of this technique is limited mainly by the amount of data recorded on two-dimensional photodetectors, i.e., the number of pixels and their size. We demonstrate that it is possible to increase the resolution linearly with the amount of recorded data by aperture synthesis as done in the radar technique but with an optical holographic field.