标准硅球直径精密测量系统的设计

基于多光束干涉的基本原理，导出了使用斐索干涉仪测量硅球直径多光束干涉光强分布的精确公式。针对目前的硅球直径测量系统忽略了多次反射对干涉信号造成的影响和系统中固有的条纹清晰度低的问题，研究了多次反射对干涉信号造成的误差，结果表明其最大光强误差可达到8％。通过对光学干涉系统结构设计和元件参数选择，最大限度地优化了干涉条纹的可见度，并设计出零背景光强标准硅球直径精密测量系统。数值模拟结果表明，该系统不仅极大地提高了干涉条纹对比度、消除了背景噪声，而且可通过改变透镜焦距调节干涉条纹的强度以达到CCD的最佳工作范围，从而提高了光强信号的测量准确度。

A Precision Measuring System for the Diameter of Single Crystal Silicon Sphere

Based on the basic principle of multiple-beam interference, an intensity distribution formula of the multiple-beam interference is derived for measuring the diameter of single crystal silicon sphere by Fizeau interferometer. Aiming at that ignoring interference signal error by multiple-beam interference in other measuring systems and low visibility of interference fringe due to the problem of interference system itself, the influence of multiple-beam interference is studied and found the error reaches to 8%. On the basis of structure design of optical system and parameter option of optical components, the visibility of interference fringe with zero background intensity is optimized. The results of digital simulation show that this system not only improve the contrast of the interference fringe and eliminate the background noises, but also adjust the interference intensity by change the focus distance of lens to fit with the optimal working range of CCD camera.