Single-shot detection of 8 unique monochrome fringe patterns representing 4 distinct directions via multispectral fringe projection profilometry

Parsa Omidi; Mohamadreza Najiminaini; Mamadou Diop; Jeffrey J L Carson

doi:10.1038/s41598-021-88136-4

Single-shot detection of 8 unique monochrome fringe patterns representing 4 distinct directions via multispectral fringe projection profilometry

Sci Rep. 2021 May 14;11(1):10367. doi: 10.1038/s41598-021-88136-4.

Authors

Parsa Omidi^{1

2}, Mohamadreza Najiminaini^{1

3}, Mamadou Diop^{1

2

4}, Jeffrey J L Carson^{5

6

7

8

9}

Affiliations

¹ Imaging Program, Lawson Health Research Institute, St. Joseph's Health Care, London, ON, N6A 4V2, Canada.
² School of Biomedical Engineering, Western University, London, ON, N6A 3K7, Canada.
³ Spectral Devices Inc., 700 Collip Circle, Suite 125, London, ON, N6G 4X8, Canada.
⁴ Department of Medical Biophysics, Western University, London, ON, N6A 5C1, Canada.
⁵ Imaging Program, Lawson Health Research Institute, St. Joseph's Health Care, London, ON, N6A 4V2, Canada. jcarson@lawsonimaging.ca.
⁶ School of Biomedical Engineering, Western University, London, ON, N6A 3K7, Canada. jcarson@lawsonimaging.ca.
⁷ Spectral Devices Inc., 700 Collip Circle, Suite 125, London, ON, N6G 4X8, Canada. jcarson@lawsonimaging.ca.
⁸ Department of Medical Biophysics, Western University, London, ON, N6A 5C1, Canada. jcarson@lawsonimaging.ca.
⁹ Department of Surgery, Western University, London, ON, N6A 5C1, Canada. jcarson@lawsonimaging.ca.

Abstract

Spatial resolution in three-dimensional fringe projection profilometry is determined in large part by the number and spacing of fringes projected onto an object. Due to the intensity-based nature of fringe projection profilometry, fringe patterns must be generated in succession, which is time-consuming. As a result, the surface features of highly dynamic objects are difficult to measure. Here, we introduce multispectral fringe projection profilometry, a novel method that utilizes multispectral illumination to project a multispectral fringe pattern onto an object combined with a multispectral camera to detect the deformation of the fringe patterns due to the object. The multispectral camera enables the detection of 8 unique monochrome fringe patterns representing 4 distinct directions in a single snapshot. Furthermore, for each direction, the camera detects two π-phase shifted fringe patterns. Each pair of fringe patterns can be differenced to generate a differential fringe pattern that corrects for illumination offsets and mitigates the effects of glare from highly reflective surfaces. The new multispectral method solves many practical problems related to conventional fringe projection profilometry and doubles the effective spatial resolution. The method is suitable for high-quality fast 3D profilometry at video frame rates.