High Value Manufacturing: Advanced Research in Virtual and Rapid Prototyping

Figure 5. Measured mask surface, shown as raw recon-

structed 3-D data points with no smoothing: (a) full mask,

(b) close up.

proposed heterodyne phase-unwrapping method per-

mitted surface-shape measurement of the mask.

4 CONCLUSION

The proposed error-compensated camera-projector

calibration method based on heterodyne phase-

unwrapping was able to detect and compensate for

spike-like errors at the phase-unwrapping stage before

proceeding with system calibration in both the simula-

tion and real-system experiments. It was demonstrated

that phase values at control points could be preserved

for use in the camera-projector stereovision-system

calibration.