Browsing by Author "Droste, Ulrich"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    Micro shape and rough surface analysis by fringe projection
    (1993) Leonhardt, Klaus; Droste, Ulrich; Schön, Stefan; Voland, Christoph; Tiziani, Hans J.
    A new microscopic fringe projection system is described. Projection of the grating and imaging of the fringes is accomplished by the same objective. The spectrum of the binary grating is spatially filtered and projected into the aperture with a lateral shift. This leads to telecentric projection and imaging under oblique incidence. Topographies of specularely as well as diffusely reflecting surfaces can be obtained. The measurement of rough, technical surfaces is demonstrated.
  • Thumbnail Image
    ItemOpen Access
    Microshape and rough-surface analysis by fringe projection
    (1994) Leonhardt, Klaus; Droste, Ulrich; Tiziani, Hans J.
    A fringe-projection system for microscopic applications, fringe-projecting microscopy, is developed and analyzed. Projection of the grating and imaging of the fringe system, modulated by the surface, are accomplished by the same high-aperture objective. The spectrum of the grating is spatially filtered and projected into the aperture with a lateral shift, which leads to a telecentric projection under oblique incidence and telecentric imaging. Topographies of specularly as well as diffusely reflecting surfaces can be obtained. The measurement of highly rough surfaces is described together with preprocessing steps. The resulting intensity distribution of the fringes is analyzed. Formulas for vertical and lateral resolution, measuring range, and dynamic range, based on noise considerations, are presented and verified by topographies of technical surfaces.