The paper introduces a new fibrescopic micro fringe projector, showing the special requirements of micro fringe projection in combination with coupling to flexible image fibre bundles. So far performed example applications, such as measurements of deep drawing tools, will be shown and difficulties of certain geometries, such as internal gearing elements with steep flank gradients are discussed. Due to the miniaturization of the fringe pattern into a 2 mm diameter fibre bundle and the decrease of resolution in the bundle, a decrease of contrast has to be accepted. That leads to a fading of the sharp edges of black/white crossovers to sine like characteristics on the detection camera. Methods for the compensation of these artifacts in the beforehand made calibration and during the acquisition of the measurement data will be presented. Fitted applications of the conventional grey code technique will be as well introduced and compared as the developing method of encoded phase shift. In the current state the newly designed fringe projector is connected to a high resolution coordinate measurement machine (CMM). Measurement data and achievable resolutions of the connected systems will as well be presented, giving information about realizable measuring volumes.

Date Published: 13 May 2013
PDF: 7 pages
Proc. SPIE 8788, Optical Measurement Systems for Industrial Inspection VIII, 878817 (13 May 2013); doi: 10.1117/12.2020440

Published in SPIE Proceedings Vol. 8788:
Optical Measurement Systems for Industrial Inspection VIII
Peter H. Lehmann; Wolfgang Osten; Armando Albertazzi, Editor(s)