传统形貌测量多采用光栅投影, 其投影条纹的非正弦性及条纹密度的限制将影响形貌测量的精度, 为了实现高密度正弦条纹投影的可调性, 采用平行光干涉投影形成明亮且对比度高的正弦条纹, 避免条纹的正弦畸变。在平行光波阵面调制下, 通过相控阵调节两光束交会角度得到所需的条纹频率, 实现条纹投影的可调性, 再将调制后双频应用到解包裹中提高解相精度。对比分析了单频和双频解包裹条件下, 一个最大高度为35.80 mm物体形貌的恢复, 其最高点恢复相对误差分别为2.7%、1.6%。实验结果表明该方法具有有效性与可行性, 具有较高的精度。

The grating projection is usually used in traditional profilometry, and the non-sinusoidal of fringe and the limitation of fringe density can affect the accuracy of topography measurement. In order to realize the adjustability of high-density sinusoidal fringe projection,the parallel light interference projection is used to form bright and high contrast sinusoidal fringe, so that the sine distortion of fringes is avoided. In parallel wavefront modulation, the desired fringe frequency is obtained by adjusting the intersection angle of the two beams by phased array, and the adjustable fringe projection is realized, then the modulated dual frequency are applied to improve the phase unwrapping accuracy. The restoration of an object with maximum height of 35.80 mm under the condition of single frequency and dual frequency unwrapping was compared, and the relative error of the highest point recovery was 2.7% and 1.6%,respectively. The experimental results show that the method is effective and feasible, and has high precision.