Scanning Projection Grating Moire Topography

نویسندگان

  • Jung-Taek Oh
  • Sangyoon Lee
  • Seung-Woo Kim
چکیده

One problem with moiré topography for 3D surface metrology is the so called 2π-ambiguity limiting the maximum step height difference between two neighboring sample points to be less than half the equivalent wavelength of moiré fringes. To cope with the ambiguity problem, a special scheme of scanning moiré technique is proposed by resorting to the frequency domain fringe analysis that is in fact originated from white light scanning interferometry. This new moiré principle of 3D measurement allows determining the absolute height of the surface without information on absolute fringe orders so that largely stepped surfaces are measured with a great improvement in accuracy.

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تاریخ انتشار 2000