基于反相条纹投影技术测量大范围变化的面形

Measurement of large distorted surface profile based on inverse projected-fringe technique

在较高精度面形测量的光学方法中,很多测量范围都受到光波波长的限制。简述了一种利用光栅投影系统来增强其垂直方向测量范围的新方法。通过投影仪来产生能够消除表面低频变化影响的变形光栅,测量该栅线经过被检面的变形图像,通过处理得到表面的高频信息,然后将高频和低频信息叠加得到表面轮廓图。通过实验模型的建立证明,该方法具有测量精度范围宽,能实时地得到表面轮廓图。

The ranges of most optical methods which are used in high precision surface profiling,are limited by the wavelength of light.A new technique based on fringe projection system is proposed,which can enlarge the measurement range in vertical direction.The deformed gratings which can decrease the low frequency impact of the surface profile,is projected back to the same surface.Then the image is captured by a CCD camera and dealt to get the high frequency information.The whole surface profile is gotten by adding the low frequency information to the high information.The new method is modeled and simulated to prove it can get the surface profile with large range precision in real time.