The encoding method has a considerable influence on the resolution, speed,
and robustness of structured light measurement systems. A synthetic encodin
g method based on spatial and temporal encodings is presented. The method c
an achieve a spatial resolution of 231 codewords with only five projected i
mages, which would require many more images if other binary codes were empl
oyed. The encoding and decoding processes are given, and experimental resul
ts verify the robustness and the reliability of the method. It is concluded
that the combination of spatial and temporal information can further impro
ve the efficiency of the encoding and make it more flexible in different ap
plications of 3-D object profile measurement. (C) 2001 Society of Photo-Opt
ical Instrumentation Engineers.