基于条纹对比度的三维测量方法由于具有垂直测量的特点, 可用于测量表面有突变的复杂物体的三维信息。本文在现有方法的基础上, 提出了一种改进的基于条纹对比度的三维测量方法。该方法利用投影仪将一组相移的正弦条纹依次投射在被测物体上, 并使被测物体位于投影仪成像面的前方, CCD相机通过一个半透半反镜从投影方向获取物体表面的条纹图像, 然后利用相移算法得到正弦条纹经物体调制的对比度分布, 最后利用该对比度和高度的对应关系恢复出物体高度。因此, 该方法只需对物体在一个位置进行扫描, 不需要改变条纹成像面位置, 测量过程更加快速简便。实验结果表明: 利用该方法可以有效地恢复出表面有突变的复杂物体的高度信息。

The profilometry based on the fringe contrast is a vertical 3D measurement technique, which can measure the complex objects with acute changes in their surfaces. A modified contrast measurement profilometry based on the previous method is proposed. In this method, sinusoidal fringes are projected on the surface of the testing object laid in front of imaging plane of the fringe and captured through a beam splitter by a CCD camera. We can obtain the fringe contrast using phase-shifting technique, and then restore the height of the object through the map of the contrast and the height. In the measurement process, we only need to capture fringe patterns in one position, without changing the image plane in several times, so it is faster and more convenient than the existing method. The experimental results prove this method can restore the height of the complex object effectively.