含参考光路的时间差法动态调焦式光学测头

Dynamic Confocal Optical Probe Based on Time Difference Measurement

为了满足对机械件、光学件和电子件等几何形貌质量控制和产品监测越来越高的要求,在动态主动调焦法测量原理的基础上,提出一种含参考光路的时间差法动态调焦式光学测头的检测方法.论述了该测头通过测量参考光路和测量光路的时间差实现位移测量的测量原理及其结构,并对这种新的测量方法进行了详细的误差分析,对该光学测头及其测量系统进行了各项实验.实验表明,含参考光路的时间差法动态调焦式光学测头及其测量系统的测量范围为±0.1mm,测量分辨力为0.075μm,线性度误差约为0.45μm.

Based on a study on an optical dynamic active confocal probe, a new method of measuring deviation focus is developed in order to meet the increasing requirements of the dimensional control and profile monitoring of the products such as mechanical, optical and electronic ones. The key point of this new method is that displacement of the turning fork is converted to time difference measurement, thus the optical and mechanical structures of the laser probe system can be simplified greatly, and its accuracy and stability are enhanced. Then a new integrated measurement system is designed with error analyzed in detail. Experiments evaluating nonlinearity and measuring range and performance are carried out. Results show that the nonlinearity error is 0.45 μm within the range of ±0.1 mm, and its response is 0.075 μm.