提出运用多投影器同时投影的反向条纹投影技术。通过测量标准样品的绝对相位,为不同角度放置的投影器产生不同的反向条纹。检测时,投影器同时投影各自的反向条纹,若物体和样品一致,在摄像机上就得到一幅消除了阴影和截断的标准正弦条纹图,若物体有变形,仅用裸眼就能判断,用简单的傅里叶变换和相位展开就能定量地描述变形。对于复杂的不连续物体也只需获取一幅条纹图就能完成检测,在很大程度上解决了阴影及相位展开的问题,实现了该类物体的在线快速检测。阐述了该技术的原理,以双投影器的反向条纹投影为例,实验验证了提出方法的有效性,并进行了相应的误差分析和应用条件讨论。

The inverse fringe projection technique using multi\|projectors simultaneously is proposed. Through the absolute phase measurement of the master object, different inverse fringes are generated for the different projectors placed in different directions. During the detection, the projectors project their inverse fringes simultaneously. If the object and master are identical, a standard sine fringe without shadow and break is got on the camera. If the object is deformed, the deformation becomes obvious, and can be evaluated quantificationally by simple Fourier transformation and phase unwrapping. Therefore, the detection of complex and discontinuous objects can be completed with only one fringe image, the problems of shadow and break are solved to a large extent, and consequently the fast online detection of this kind of objects is realized. The principle of this technique is expatiated, and the validity is proved by taking the system of two projectors for example. The analysis of error and requirement of application are also presented.