Effect of fringe width and camera-projector baseline distance on z-direction measurement accuracy in whole-space tabulation method

To optimize the measurement accuracy of structured-light systems based on the Whole-Space Tabulation Method (WSTM), we made a 3-D shape measuring device and investigated the effect of fringe width and camera-projector baseline distance on z-direction measurement accuracy through controlled variable experiments. Seven sets of fringe patterns with different widths and four baseline distances were tested. Experimental results show that within the experimental parameter range, the z-direction measurement accuracy of the WSTM system significantly improves with decreasing fringe width and increasing baseline distance, which consistent with theoretical predictions. Specifically, the average standard deviation of the combination of 40-pixel fringes and 250 mm baseline distance reached 20 μm, which is 80.8% higher than that of the combination of 100-pixel fringes and 100 mm baseline distance. The research results provide an experimental basis for parameter optimization and engineering design of the WSTM system.