title: Diffraction-induced coherence levels.
abstract: We examined the influence of complex diffraction effects on low-coherence fringes created for high-aspect depth-to-width ratio structures called trenches. The coherence function was analyzed for these micrometer-wide trenches and was registered with a white-light interference microscope. For some types of surface structure we observed that additional low-coherence fringes that do not correspond directly to the surface topology are formed near the sharp edges of the structures. These additional coherence fringes were studied by rigorous numerical evaluations of vector diffractions, and these simulated interference fields were then compared with experimental results that were obtained with a white-light interference microscope.
authors.affiliation: Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei-shi, Tokyo 184-8588 Japan.
authors.forename: Alexander
authors.initials: A
authors.lastname: Tavrov
authors.forename: Joanna
authors.initials: J
authors.lastname: Schmit
authors.forename: Norbert
authors.initials: N
authors.lastname: Kerwien
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Osten
authors.forename: Hans
authors.initials: H
authors.lastname: Tiziani
mesh_terms: D003198:Computer Simulation; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008857:Microscopy, Interference / Q000379:methods*; D008954:Models, Biological; D019047:Phantoms, Imaging; D012031:Refractometry / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence / Q000295:instrumentation / Q000379:methods*