余弦变换三维物体轮廓术的改进

利用余弦变换获取三维物体面形的技术已得到了应用。但该技术在测量高度梯度 (垂直光栅方向 )变化率较大的物体时会产生误差 ,高度梯度变化率大到某一值时 ,将不再合适。为此采用余弦光栅能较好地解决这一问题 ,它可将测量范围扩大到原来的 3倍。从理论上证明了将物体高度变化率大的一面朝光栅放置 ,可以进一步拓宽余弦变换法的测量范围 ,以文中的系统为例 ,其扩大倍数可达到原来的 5 7倍 ,远大于 3倍

Improved cosine transform profilometry for the automatic measurement of 3-D objcet shapes

The profilometry of 3 D diffuse objects by using cosine transformation has been applied.But the technique produces errors when measuring height gradient variability(perpendicular to the direction of the grating)for the object is large enough.Therefore,it is not available when the height gradient variability reaches a certain value.In this paper,it is explained that the problem can be solved and the measuring range is expanded by three times by using cosine grating.It is also proved that the measuring range is expanded more by placing the object facing the grating reasonably,system mentioned,the multiple is 57,greater than 3.