Abstract
Shape measurement using the whole-space tabulation method (WSTM) is a non-contact approach that has high accuracy. However, unfocused images affect measurement accuracy in practical applications. Errors occur in the analyzed phase near boundary areas with large contrast in unfocused images. In this study, measurement error is reduced. First, experiments are performed to confirm that low reflectance areas are significantly affected by high reflectance areas. Second, an error reduction method using two cameras for the WSTM is proposed. When two cameras capture images from the left and right sides of the projector, the phase-coordinate tables are nearly reversed. Thus, the measurement errors are also nearly reversed in the measurement results of these two cameras. The measurement accuracy is increased by averaging the two sets of measurement results. The WSTM measurement results of the two cameras share the same coordinate system because the WSTM uses a table with a shared reference plane. Therefore, the synthesis of the left and right measurement results is simple using the WSTM.
