Simple and Robust Digital Holography Used for Phase Imaging

Digital holography is a digitized holography, which is very suitable for phase imaging of microscopic object. An off-axis lensless Fourier transform digital holographic system is built. The recording and numerical reconstruction of digital hologram is analyzed. The model of phase aberration in numerical reconstruction is presented. Experimental investigations have been performed for a USAF test target. The accurate phase image is obtained by an automatic phase aberration compensation procedure. The lateral resolution of 2.76 mum and the axial resolution of no larger than 10 nm have been achieved experimentally. The results are coincident with the theoretical predictions. Also, the height profiles of the test target is obtained and given.