Two-wavelength method for endoscopic shape measurement by spatial phase-shifting speckle-interferometry.
A two-wavelength method for endoscopic topography reconstruction is introduced that can be applied to out-of-plane sensitive electronic-speckle-pattern interferometry systems based on rigid endoscope imaging systems. The surface measurement is performed by detection of the phase-difference distribution affected by a change in the applied laser wavelength. Furthermore, the off-axis endoscopic illumination geometry is taken into account by an approximation. Experimental results of the characterization of the endoscopic surface reconstruction technique and the measurement accuracy obtained are described and discussed. Finally, the applicability of the method is demonstrated with results from the topographic reconstruction of a free-form surface.
Kandulla
Jochen
J
Laboratory of Biophysics, University of Münster, Robert-Koch-Strasse 45, 48129 Münster, Germany. kandulla@mll.mu-luebeck.de
Kemper
Björn
B
Knoche
Sabine
S
von Bally
Gert
G