光学学报, 2014, 34 (s1): s112004, 网络出版: 2014-07-03
基于斜率传感的平面元件面形检测技术研究
Study on the Surface Shape Measurement of Planar Element Based on Slope Sensor Method
测量 光学测试 面形 矢量多项式 偏折术 斜率 measurement optical testing surface shape vector polynomials deflectometry slope
摘要
斜率传感的平面元件面形检测是基于光线反射的几何原理和相位测量偏折术方法的光学面形检测技术,它能够快速、简便、准确地测量非球面面形及透射光学元件波前,也称偏折术或逆哈特曼测试系统。推导了平面元件斜率检测公式和面形恢复算法,使用可编码条纹的液晶显示器作为照明光源,四步相移法来识别显示器像素点坐标。针孔摄像机采集被测表面对条纹所成的像,将该系统用于有机玻璃板在加热条件下的面形测量,经计算机处理得到被测表面斜率数据。用方形域内标准正交矢量多项式拟合计算斜率数据得到有机玻璃板面形信息,对面形信息对比分析,然后对有机玻璃板在加压条件下的斜率变化进行了检测,与激光反射法计算的斜率变化结果进行对比。结果表明,该测试系统有动态范围大、装置简单、速度快、非接触、测试精度高等特点,为实际生产和应用提供了一种检测平面面形及动态变化过程监测的新手段。
Abstract
Measurement of planar element using slope sensor method is based on the geometry of the fringe reflection and phase measuring deflectometry method which can be used to measure aspherical shapes and transmission optical element rapidly, simply and accurately. It can be called deflectometry or Hartmann test system in reverse. We go through the derivation of measurement equation of planar element slope and wavefront reconstruction algorithm. By using an LCD screen with programmable fringe as illumination source, phase shifting method of four step is used to recognize display pixel coordinates, and a camera with small aperture images the surface under test. We apply this system to the measurement of acrylic plastic plate surface under the condition of and heating. The slope data can be obtained after operating these pictures by computer, and we use orthonormal vector polynomials fitting in a square area to calculate the surface shape of mirror under test, then analyze the surface information. And we use this system to test the slope change of acrylic plastic plate surface under the condition of stressing, and compare with the result of the laser-reflection method. The results show that the test system has a large dynamic range and is simple, rapid, non-contacting, and high-precision. It can supply a new method to test the planar surface shape and the dynamic changes of the object surface shape in practical production and application.
鄂可伟, 李大海, 李萌阳, 赵霁文, 李水艳, 张充, 代贞强, 王琼华. 基于斜率传感的平面元件面形检测技术研究[J]. 光学学报, 2014, 34(s1): s112004. E Kewei, Li Dahai, Li Mengyang, Zhao Jiwen, Li Shuiyan, Zhang Chong, Dai Zhenqiang, Wang Qionghua. Study on the Surface Shape Measurement of Planar Element Based on Slope Sensor Method[J]. Acta Optica Sinica, 2014, 34(s1): s112004.