Abstract

Digital Holographic Microscopy (DHM) allows quantitative multi-focus phase contrast imaging that has been found suitable for technical inspection and quantitative live cell imaging. The combination of DHM with fast and robust auto-focus algorithms and a calibrated imaging system enables the determination of axial sample displacements. The evaluation of quantitative DHM phase contrast images permits also an effective detection of lateral object movements. Thus, data for 3D tracking is provided. Multi-wavelength techniques open up prospects for an increased phase resolution in DHM by reduction of parasitic interference effects due to multiple reflections within the measurement setup. For this purpose, the generation of short coherence properties by tunable laser light has been investigated for application in DHM. Results from investigations on sedimenting erythrocytes in suspension demonstrate that DHM enables (automated) quantitative dynamic 3D tracking of multiple cells without mechanical focus adjustment. Furthermore, it is shown that multi-wavelength techniques enhance the phase resolution in quantitative digital holographic cell imaging.

© 2009 OSA/SPIE