New realistic 3D surface microtopography visualization technique

摘要

Abstract: We have developed a new realistic 3-D microsurface visualization technique utilizing optical phase-shifting interferometry (PSI). First, we measure the surface topography directly by determining the phase of the wavefront reflected from the surface of the object. The phase information is obtained by shifting the phase of one beam of the interferometer by a known amount and measuring the intensity of the interferometer for many different phase shifts. A phase difference map between the reference and object wavefronts is then calculated from the measured intensities. The vertical resolution is on the order of a few Angstroms. Second, we extend phase-shifting interferometry to a measurement of surface reflectivity. The measured reflectivity is not affected by any variations associated with the light source across the entire illumination field. Third, both the measured surface height data and the reflectivity images are fed into a workstation where advanced computer graphics algorithms are applied. The surface height data are used to generate the 3-D surface profile, which is then shaded by the reflectivity image, resulting in a realistic 3-D image. We will present the theoretical analysis, system setup, experimental measurements, and examples of realistic 3-D microscopic surface images.!7