薄膜干涉的衬比度研究

Research on Contrast Ratio of Thin Film Interference

在薄膜干涉的相关教学中,教师和学生的关注点一般在于产生干涉的位置以及干涉条纹的分布状况,对干涉条纹的衬比度往往讨论的较少,而干涉场的衬比度对基于干涉的测量与制造是非常重要的.以菲涅尔反射公式为基础,从薄膜与背景材料的折射率差和光在薄膜上的入射角两方面,研究了薄膜干涉的衬比度,得到了一些具有价值的结论,这些结论对于学生进一步理解薄膜干涉,以及基于干涉的精密测量和微结构制造,具有一定的参考价值.

In the teaching of thin film interference,teachers and students often focus on the interference distribution.The contrast ratio of the interference fringes,which is often less discussed,is important for the measurement and manufacturing based on interference.According to the Fresnel reflection theory,this paper investigates the contrast ratio of thin film interference from two aspects.One is the refractive index difference between the thin film and background material,the other is the incident angle of light on the thin film.Some important results have been achieved,which will help students understand thin film interference,precision measurement,and micro-structure fabrication based on interference.