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Sinusoidal patterns are widely employed in fringe projection profilometry (FPP) for high-accuracy measurements. However, in practice, random factors, such as camera noise, will seriously affect the accuracy of sinusoidal patterns. This article presents a smoothed-truncated-sine (STS) pattern design method that can achieve higher accuracy than sinusoidal patterns under the same noise. By insensitive harmonic modulation, the STS pattern can achieve a higher signal-to-noise ratio (SNR) to reduce the random error and maintain the amplitude of sensitive harmonics low to restrain the systematic error. First, the error mechanism is analyzed, and the error model is established for the phase-shifting algorithm, taking into account the resistance of the phase-shifting algorithm to part of high-order harmonic errors. Second, an STS pattern is proposed and optimized based on the error model. The parameters of the STS pattern are optimized to achieve a high SNR and a small phase error, resulting in improved performance of the multiple-step phase-shifting algorithm, especially when the number of steps is large. Simulations and experiments demonstrate that the proposed method achieves higher accuracy than sinusoidal patterns and that the maximum error reduction ratio exceeds 20% if the number of steps is sufficiently large in sinusoidal FPP.

Pulmonary hypertension (PH) is a disease of pulmonary artery stenosis and blockage caused by abnormal pulmonary artery smooth muscle cells (PASMCs), with high morbidity and mortality. High levels of reactive oxygen species (ROS) in pulmonary arteries play a crucial role in inducing phenotypic switch and abnormal proliferation of PASMCs. However, antioxidants are rarely approved for the treatment of PH because of a lack of targeting and low bioavailability. In this study, the presence of an enhanced permeability and retention effect (EPR)‐like effect in the pulmonary arteries of PH is revealed by tissue transmission electron microscopy (TEM). Subsequently, for the first time, tungsten‐based polyoxometalate nanodots (WNDs) are developed with potent elimination of multiple ROS for efficient treatment of PH thanks to the high proportion of reduced W5+. WNDs are effectively enriched in the pulmonary artery by intravenous injection because of the EPR‐like effect of PH, and significantly prevent the abnormal proliferation of PASMCs, greatly improve the remodeling of pulmonary arteries, and ultimately improve right heart function. In conclusion, this work provides a novel and effective solution to the dilemma of targeting ROS for the treatment of PH. Tungsten‐based polyoxometalate nanodots (WNDs) contain a high proportion of reduced W5+. WNDs are enriched in pulmonary artery smooth muscle cells (PASMCs) and scavenged reactive oxygen species (ROS) because of the enhanced permeability and retention (EPR)‐like effect of the pulmonary artery of pulmonary hypertension (PH). WNDs inhibit the abnormal proliferation and phenotypic switch of PASMCs, thereby suppressing pulmonary artery remodeling in PH.