Double-frequency TPU method with geometric constraints and polynomial adjust

The main problem in the double-frequency algorithms is the sensitivity to noise, it is amplified when the ratio between the high frequency and the low one is large. Different proposals have been published with the intention of reducing the impact of noise. One of the most effective is the Hyun and Zhang’s algorithm which include geometric constraints to unwrap the low-frequency map without needing the unit-frequency phase map. Inspired in the Hyun and Zhang’s work, in this paper a double-frequency TPU algorithm is proposed. This does not require the calibration of the projector and instead a polynomial adjust is used to related the variations in z with the low-frequency unwrapped phase maps. Experiments successfully verified the performance of the proposed method, it was tested with low-frequency phase maps different from unit-frequency map.