应用时域相位解包方法的三维形貌测量系统

为了解决投影法三维形貌测量中测量点误差受相邻点影响的问题,投射计算机按照所需频率和相位生成的正弦条纹,利用时域相位解包算法实现每个测量点的独立计算。为了降低测量复杂形貌时因栅距变化产生的误差,发展了虚参考平面法。列举了在真人头面部和鼠标测量中的应用。实验结果表明,在进行复杂形貌三维测量时,采用时域相位解包方法可以抑制误差的扩散,不受不连续区域的影响。整个测量过程可在5s之内完成,测量平面时精度可达0.78%。

3-D profilometry system using the temporal phase unwrapping method

Optical positioning measurements are affected by error dependence between adjacent measuring points. A multifrequency sinusoidal computer generated grating with variable frequency and phase was developed to independently measure each point location with a temporal phase unwrapping method used to evaluate results. A virtual reference plane technique was developed to reduce the error due to grid pitch changes while measuring complex shapes. The system was applied to real examples like a human face and a computer mouse. These measuring results show that the temporal phase unwrapping method inhibits error spreading and reduces the effects of surface discontinuities. This system needs only 5 s to measure a shape with an accuracy of more than 99%.