Zhang Liang, Chen Qian, Zuo Chao, Feng Shijie
Appl Opt. 2018 Feb 20;57(6):1378-1386. doi: 10.1364/AO.57.001378.
Fringe projection profilometry has been widely used in many fields for its advantages such as high speed, high accuracy, and robustness to environmental illumination and surface texture. However, it is vulnerable to high dynamic range (HDR) objects. To this end, we propose a technique that can enhance the dynamic range of the fringe projection profilometry system. According to the surface reflectivities of the measured objects, several groups of fringe patterns with optimal light intensities are generated based on the intensity response function of a camera. The HDR fringe images are acquired by fusing these fringe patterns, and a three-step phase-shifting algorithm is used to obtain the unwrapped phase from the fused images. Experimental results demonstrate that the proposed technique can accurately measure objects with an HDR of surface reflectivity variation.
条纹投影轮廓术因其具有高速、高精度以及对环境光照和表面纹理具有鲁棒性等优点，已在许多领域得到广泛应用。然而，它对高动态范围（HDR）物体较为敏感。为此，我们提出一种能够提高条纹投影轮廓术系统动态范围的技术。根据被测物体的表面反射率，基于相机的强度响应函数生成几组具有最佳光强的条纹图案。通过融合这些条纹图案获取HDR条纹图像，并采用三步相移算法从融合图像中获得展开相位。实验结果表明，所提出的技术能够准确测量表面反射率变化具有HDR的物体。
