发散圆形条纹投影的共轴三维测量方法

Coaxial Three-Dimensional Measurement Method of Divergent Circular Fringe Projection

在基于条纹投影的三维测量方法中,圆形正弦条纹比线性条纹具有更高的相位灵敏度。提出一种基于发散投影光线几何关系的圆形条纹投影共轴三维测量方法。沿光轴方向移动投影仪使得物面上的条纹发生变化,利用电荷耦合器件(CCD)采集对应的条纹图,并从中解算出不同的相位场。利用投影仪位移带来的投影光线变化建立起相位信息和物体高度间的约束,不需要获取复杂的系统参数就能重建物面的高度信息,减少测量中存在的阴影和遮挡问题。仿真和实验结果均表明了所提方法的有效性和实用性。

In the three-dimensional measurement methods based on fringe projection,circular sinusoidal fringes have higher phase sensitivity than linear fringes.Therefore,a coaxial three-dimensional measurement method of circular fringe projection is proposed,which is based on the geometric relationship of divergent projection rays.Specifically,the fringes on the object surface are changed by the movement of the projector along the optical axis,the charge-coupled device(CCD)is employed to collect the corresponding fringe patterns,and different phase fields are calculated from these fringe patterns.The constraints between phase information and height of the object are established by the use of the change in projection rays caused by the movement of the projector.In this way,the height information of the object surface can be reconstructed without obtaining complex system parameters,and the problems of shadow and occlusion can be reduced in the measurement.Simulations and experimental results verify the effectiveness and practicability of the proposed method.