An automatic method for increasing the numerical aperture of a digital holography recording system

A major issue so far for digital holography has been the limited number of pixels of currently available detectors, such as CCD sensors, which allows a spatial resolution significantly lower than that of a holographic plate. This is an even more sever limitation when IR sensors such as microbolometers are taken into consideration. In order to increase the numerical aperture of such systems, we developed an automatic technique which is capable to record several holograms and stitch them together before reconstruction. This method can cope with some of the inherent differences of the image structures and tone dynamics of recorded holograms. The joint holograms have been applied for reconstruction of an image by means of numerical and optoelectronic reconstruction processes and they show significant increase of quality.