Improved three-dimensional profile measuring method based on intensity-ratio measurement

Abstract. In the existing intensity-ratio measuring methods, unwrapping the intensity ratio may be erroneous or even fail when measuring complex and isolated objects. This paper presents an improved three-dimensional (3-D) profile measuring method based on intensity-ratio measurement. Two shifting triangular patterns are projected to generate a triangular intensity-ratio distribution, and a Ronchi grating is projected to correctly divide the triangular intensity-ratio regions. Then, an absolute intensity ratio is retrieved point-by-point with the periodic label of the projected Ronchi grating. Finally, the intensity-ratio-to-height mapping algorithm is used to reconstruct the 3-D surface shape. The experimental results have demonstrated the feasibility and validity of the proposed method in restoring 3-D surface shape of the complex and isolated objects.

[1]  Qican Zhang,et al.  3-D shape measurement based on complementary Gray-code light , 2012 .

[2]  Zongkai Yang,et al.  3D profile measurement based on estimation of spatial shifts between intensity ratios from multiple-step triangular patterns , 2013 .

[3]  Jorge L. Flores,et al.  Gray coded trapezoidal fringes for 3-D surface-shape measurement , 2014, Optics & Photonics - Optical Engineering + Applications.

[4]  Jonathan Kofman,et al.  Two-step triangular-pattern phase-shifting method for three-dimensional object-shape measurement , 2007 .

[5]  Hsin-Chu Liu,et al.  Optical three-dimensional sensing by phase measuring profilometry , 1989 .

[6]  Jean-Yves Bouguet,et al.  Camera calibration toolbox for matlab , 2001 .

[7]  K. Creath.  V Phase-Measurement Interferometry Techniques , 1988 .

[8]  Jian Li,et al.  An Improved Fourier Transform Profilometry , 1989, Other Conferences.

[9]  W Li,et al.  Large-scale three-dimensional object measurement: a practical coordinate mapping and image data-patching method. , 2001, Applied optics.

[10]  M. Takeda,et al.  Fourier-transform method of fringe-pattern analysis for computer-based topography and interferometry , 1982 .

[11]  V. Srinivasan,et al.  Automated phase-measuring profilometry of 3-D diffuse objects. , 1984, Applied optics.

[12]  Takeo Miyasaka,et al.  DEVELOPMENT OF REAL TIME 3-D MEASUREMENT SYSTEM USING INTENSITY RATIO METHOD , 2001 .

[13]  Jonathan Kofman,et al.  Multiple-step triangular-pattern phase shifting and the influence of number of steps and pitch on measurement accuracy. , 2007, Applied optics.

[14]  Zhengyou Zhang,et al.  A Flexible New Technique for Camera Calibration , 2000, IEEE Trans. Pattern Anal. Mach. Intell..

[15]  M. Chang,et al.  Phase-measuring profilometry using sinusoidal grating , 1993 .

[16]  Robert A. Hummel,et al.  Experiments with the intensity ratio depth sensor , 1985, Comput. Vis. Graph. Image Process..

[17]  Fu-Pen Chiang,et al.  Trapezoidal phase-shifting method for three-dimensional shape measurement , 2005 .

[18]  Qican Zhang,et al.  Dynamic 3-D shape measurement method: A review , 2010 .