2.1 Optical Profiler Modifications
Imaging live cells required that the optical profiler be modified to accommodate the dispersive effects of the liquid cell media in the optical path. Schematically, this required replacement of the high magnification Mirau objective (20x) in the DMEMS 1100 optical profiler with a Michelson objective module and a separate illumination module (Fig. 5). The system is designed to optimize a conventional profiler’s performance when used to test a sample covered by a dispersive medium in the optical path of the test beam T. This required that a compensating, dispersive cell be placed in the reference path. Fig. 6 shows a full schematic of the modified system.
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Fig. 5. Modified Michelson objective shown with illumination source and dispersive compensating cell.
Fig. 6. Schematic representation of a Michelson type interferometric objective.
2.2 Nanomirror Fabrication
White light Vertical Scanning Interferometry (VSI) has accuracy better than 1 nm in the z-axis . We constructed nanomirrors to act as tiny retroreflectors on the cell membrane, which we would tracked with in real time with VSI. Fig. 7 shows an SEM image of a 10 micron diameter, 2 micron thick nanomirror.
Proc. of SPIE Vol. 6293 629301-5