Three-dimensional imaging technique based on Gray-coded structured illumination

Three-dimensional (3D) imaging technique based on structured illumination has been deeply studied and widely applied in recent years. Among numerous 3D imaging methods, the imaging technique based on Gray-coded structured illumination has been applied in industrial inspection, digitalization of antique, biomedicine detection and so on, owing to its robustness and anti-noise ability. To realize 3D imaging, the projected Gray-coded pattern can either be used to modulate the height information or be used to assist acquisition and computation of the height information of the tested object. In this paper, a review was given to introduce principles and progresses of the imaging techniques based on Gray-coded structured illumination and the research achievements of the author's research group about this technique were also shown. In addition, the advantages, disadvantages and application scope of binary Gray-coded patterns in 3D shape measurement were discussed and the developing trends of this technique was pointed out as well.