S Zhang and S-T Yau, "Three-dimensional data merging using Holoimage," Opt. Eng., 47(3), 033608, 2008 (Cover Feature); doi: 10.1117/1.2898902
Three-dimensional data merging is vital for full-field threedimensional 3D shape measurement. All 3D range data patches, acquired from either different sensors or the same sensor in different viewing angles, have to be merged into a single piece to facilitate future data analysis. A novel method for 3D data merging using Holoimage is proposed. Similar to the 3D shape measurement system using a phaseshifting method, Holoimage is a phase-shifting–based computer synthesized fringe image. The 3D information is retrieved from Holoimage using a phase-shifting method. If two patches of 3D data with overlapping areas are rendered by OpenGL, the overlapping areas are resolved by the graphics pipeline, that is, only the front geometry can be visualized. Therefore, the merging is performed if the front geometry information can be obtained. Holoimage is to obtain the front geometry by projecting the fringe patterns onto the rendered scene. We also demonstrated that each point of the geometry in the overlapping area can be obtained by averaging the corresponding point of the geometries reconstructed from Holoimage for each patch. Moreover, using Holoimage, the texture can also be obtained. Both simulation and experiments demonstrated the success of the proposed method.