Fig. 1. Generated projection patterns. (a) Embedded speckle pattern; (b) one of composite fringe patterns

Fig. 2. Schematic of preparation before measurement. (a) Principle diagram of measuring system; (b) calculated wrapped phase and reference speckle; (c) wrapped phase maps at different heights for building LUT; (d) establishment of wrapped phase-to-height LUT of one pixel along light ray l; (e) reference speckle images at different heights for saving in advance

Fig. 3. Comparison of reconstruction results and error rates between NCC and ZNCC. (a) Plaster model and corresponding speckle pattern; 3D measurement results with (b) NCC and (c) ZNCC; (d) (e) corresponding error point distributions

Fig. 4. Principle diagram of height reconstruction. (a) Principle diagram of measuring system; (b) corresponding wrapped phase and speckle; (c) several candidate heights from LUT; (d) speckle correlation computation between reference speckle subareas corresponding to candidate heights and target speckle subarea centered on point S'_p(x,y)

Fig. 5. Experimental setup of 3D measuring system

Fig. 6. Experimental results of accuracy evaluation. (a) Workpieces to be measured; (b) 3D reconstruction results and height differences among three planes; (c) error distributions

Fig. 7. 3D reconstruction results of single object. (a) Plaster model; (b) corresponding wrapped phase map and speckle pattern; (c) 3D measurement result before compensation and enlarged detail chart; (d) final 3D measurement result and enlarged detail chart

Fig. 8. 3D reconstruction results of isolated objects. (a) Portrait plaster model and clock model; (b) corresponding wrapped phase maps and speckle patterns; (c) 3D measurement results before compensation and enlarged detail charts; (d) final 3D measurement results and enlarged detail charts

Fig. 9. 3D measurement of dynamic scene. (a) Wrapped phase maps at different moments; (b) speckle patterns at different moments; (c) corresponding 3D reconstruction results