Abstract The fringe projection profilometry with sinusoidal patterns based on phase-shifting algorithms is commonly distorted by the nonlinear intensity response of commercial projector. In order to solve this issue, sinusoidal width modulation is presented to generate binary sinusoidal patterns for defocusing the projection. However, the residual errors in the phase maps are usually notable for highly accurate three-dimensional shape measurements. In this paper, we propose the fringe patterns of the sinusoidal, square, and triangular periodic waveforms with seven-step phase-shifting algorithm to further improve the accuracy of three-dimensional profile reconstruction. The absolute phase values are calculated by using quality guided path unwrapping. We learn that by properly selecting fringe patterns according to the target shape, the undesired harmonics of the measured surface have negligible effect on the phase values. The experiments are presented to verify the imaging performances of three fringe patterns for different testing targets. The triangular fringe patterns are suitable for the shape measurements of complex targets with curved surfaces. The results provide a great possibility for high-accuracy shape measurement technique with wider measuring depth range.

中文翻译：

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数字条纹投影轮廓仪的相位模式调制研究

摘要 基于相移算法的正弦图案条纹投影轮廓测量通常会因商用投影仪的非线性强度响应而失真。为了解决这个问题，提出了正弦宽度调制来生成用于散焦投影的二进制正弦图案。然而，相位图中的残差对于高精度的三维形状测量通常是显着的。在本文中，我们提出了七步相移算法的正弦、方波和三角周期波形的条纹图案，以进一步提高三维轮廓重建的精度。绝对相位值是通过使用质量引导路径展开来计算的。我们通过根据目标形状正确选择条纹图案来了解到，被测表面的不想要的谐波对相位值的影响可以忽略不计。通过实验验证了三种条纹图案对不同测试目标的成像性能。三角形条纹图案适用于曲面复杂目标的形状测量。研究结果为更广泛的测量深度范围的高精度形状测量技术提供了很大的可能性。