Intensity-optimized dithering technique for three-dimensional shape measurement with projector defocusing

• Novel findings on dithering technique optimization: the optimization should be performed in the intensity domain rather than in the phase domain.
• Significantly and consistently enhanced the measurement quality of the binary defocusing when the projector is nearly focused.
• Could drastically enhance the capability of the binary defocusing technique.

Our previously proposed phase-based optimization method [1] has proven successful in improving the measurement quality when a dithering technique is used. This paper presents an intensity-based optimization method for 3D shape measurement with binary dithering techniques. Both simulations and experiments find that the phase-based optimization method can generate high-quality phase under a given condition, but it is sensitive to the amount of defocusing. In contrast, the proposed intensity-based optimization method can consistently generate high-quality phase with various amounts of defocusing.