Eliminating phase error caused by multi-path effect for phase measuring profilometry

The multi-path effect can cause undesirable phase error in regions with dramatically varied albedo. This paper proposes an effective method to correct such an error. The difference map of modulation is generated to precisely detect regions affected by the multi-path effect, and the phase error in the detected regions is corrected according to neighbor phase. Experimental results demonstrate the validity of the proposed method and show a reduction by 57.3% in the root mean square of phase errors.