基于数字全息的回转类机械零件三维显示

Three-Dimensional Display of Rotary Mechanical Parts Based on Digital Holography

提出了一种针对弱漫反射物体在重建平面内的重建像位置预标记法。利用物体上某个特定区域的镜面反射光作为物光,获得全息图,对+1级重建像所在区域进行预标记;不改变物体位置,对物体上的漫反射面发出的物光进行全息记录,在原预标记区域提取弱漫反射物体的重建像。改变照明光倾角方式,并结合FIMG4FFT方法,获取特定视角下的物体三维轮廓。获得多个视角的三维轮廓后,提出利用粒子群算法将非线性方程组的求解问题转化为优化问题求解拼接参数,实现圆柱坐标系下的多视角物体三维轮廓拼接。误差标定实验证明最大相对测量误差为5.6%。所提方法成功地对螺纹表面进行多视角三维轮廓获取、拼接,实现了回转类零件的三维全息显示。

A pre-labeling method for the reconstructed image position of a diffuse reflector in the reconstructed plane is proposed.Firstly,a hologram is obtained by using the specular reflected light of a specific area on the object as object light,and the area where the+1 st-order reconstruction image is located is pre-marked.Then,without changing the position of the object,the object light emitted by the diffuse reflector on the object is holographically recorded,and weak diffuse reflection is extracted from the original pre-marked area.By changing the inclination of illumination light and combining FIMG4 FFT method,the three-dimensional contour of the object at a specific viewing angle is obtained.After obtaining the three-dimensional contours at multiple viewing angles,the problem of solving non-linear equations is transformed into an optimization problem by using particle swarm optimization(PSO)to solve the stitching parameters,so as to achieve the final stitching of the three-dimensional object contours at multiple viewing angles in cylindrical coordinates.The error calibration experiment shows that the maximum relative measurement error is 5.6%.The proposed method can successfully acquire and stitch the threaded surface with multi-view and three-dimensional contours,and realize the three-dimensional holographic display of rotary parts.