基于平行平板的折射率高精度非接触测量

摘要

Since conventional refractive index measurement methods such as least deviation angular test method, auto-collimation method and critical angle method require a sample prism specially made for such measurement, they are time-consuming and complicated. Non-contact measurement of refractive index based on parallel surface plate was used to ensure the integrity of the material to be measured and achieve automatic measurement. The results show that the method is easy to realize automatic measurement and its accuracy could be achieved by choosing apropriate measurement angles. The obtained rotation angle accuracy is △a = 0. 003°(10"), the guide precision is △l = 0. 000 8 mm and the measurement accuracy of parallel surface plate thickness is △d=0. 001 mm .%常用的测量折射率的方法如偏向角法、自准直法、临界角法、V棱镜法等,这些方法通常需特制三棱镜与待测件.待测样品不一致且过程复杂,测试定标周期长,难于自动化.为了保证待测材料的完整及实现自动化测量,进行了基于平行平板的折射率非接触测量的尝试.运用该方法进行折射率的测量,不需特制三棱镜并且待测件与待测样品一致.分析表明,通过选择合适的测量角度,该方法旋转角度精度为△s=0.003°(即10”),导轨精度为△L=0.000 8 mm,平行平板厚度测量精度为△d=0.001mm.