Affiliation: | a Department of Physical Optics, School of Physics, A28, University of Sydney, Sydney NSW 2006, Australia b Department of Physics II, Royal Institute of Technology, Stockholm, Sweden c Australian Key Centre for Microscopy and Microanalysis, University of Sydney, Sydney NSW 2006, Australia |
Abstract: | A low-coherence Linnik interference microscope using high numerical aperture optics has been constructed. The system uses a tungsten halogen lamp and Köhler illumination, with separate control over field and aperture stops, so that experiments can be conducted with a range of different operating conditions. The novel feature of the system is the use of an achromatic phase-shifter operating on the principle of the geometric phase, achieved by using a polarising beam splitter, a quarter wave plate and a rotating polariser. Image information is extracted from the visibility of the fringes, the position of the visibility peak along the scanning axis yielding the height of the test surface at the corresponding point. |