Institute of Disaster Prevention, SanHe, HeBei, 065201, China.
Faculty of Materials and Manufacturing, Beijing University of Technology, Beijing, 100124, China.
Micron. 2021 Apr;143:103022. doi: 10.1016/j.micron.2021.103022. Epub 2021 Jan 29.
Aiming at the problem of 3D surface reconstruction of small height objects, a method based on the scanning principle with thin structured light is proposed. The laser fringe is produced by a laser light source. It scans the surface of small height object under the control of a precise motion control system, and is integrated with a stereo light microscope and two cameras to form a complete structured light profilometry system. This method is very suitable for 3D surface reconstruction of small height objects. In order to deal with the phenomenon of "cracking" and local uneven brightness in microscope fringe image, the fringe image sequence is captured under different camera exposure parameters, and the quality of fringe image is improved by image fusion. The location of pixels on the center line of laser stripes is detected by the Loess local second-order fitting method, and the positions of these pixels are smoothed and predicted by using the Lowess local linear fitting method. The deformation of the laser stripe center curve is calculated by constructing a baseline, and the 3D surface reconstruction of the object with small height is realized in the image space. Taking the small characters on the surface of Chinese coins and human hair as test samples, their 3D surfaces are constructed by using the method proposed in this paper. The reconstructed 3D surface shapes are highly consistent with the real 3D surface shapes of objects.
针对小高度物体的三维表面重建问题,提出了一种基于扫描原理的薄结构光方法。激光条纹由激光光源产生。它在精密运动控制系统的控制下扫描小高度物体的表面,并与立体光显微镜和两个相机集成在一起,形成完整的结构光轮廓测量系统。这种方法非常适合小高度物体的三维表面重建。为了解决显微镜条纹图像中的“开裂”和局部亮度不均匀现象,在不同的相机曝光参数下捕获条纹图像序列,并通过图像融合来提高条纹图像的质量。通过洛厄斯局部二阶拟合方法检测激光条纹中心线上像素的位置,并使用低通局部线性拟合方法对这些像素的位置进行平滑和预测。通过构建基线来计算激光条纹中心曲线的变形,从而在图像空间中实现小高度物体的三维表面重建。以中国硬币表面的小字符和人类头发作为测试样本,使用本文提出的方法对它们的三维表面进行了构建。重建的三维表面形状与物体的真实三维表面形状高度一致。