1、 摘 要 透明的介质，如玻璃、水，在日常生活和实践中有着广泛的应用，人们不仅 可以通过其反射性质扩大视野，又可以利用其折射性质改变光的传播方向。因此， 准确而快速的测量透明介质的折射率，有利于更好的了解透明介质的性质并发挥 它的作用。而光拍频法测量透明介质的折射率是光学实验中一个重要而典型的实 验，用光拍频测光速是该实验的一个重要内容，它既利于掌握光拍频测量光速的 原理，又兼有对 LSIII 型光速测定仪测量透明介质折射率实验原理和实验方法 的了解。由于光的频率极高（Hzf 14 10 ），光电检测器的光敏面不能反应这样 快的光强变化，它仅能反应 8 10Hz 以下的光强变化，并产生与该变化相
2、应的交变光 电流，所以用光拍频的形式转化成频率较低的载波进行检测。 关键词：关键词：光速测量；光拍法；光程差；折射率测量 ABSTRACT The transparent medium, like the glass, the water, have the widespread application in the daily life and the practice, not only the people may through its reflection nature expansion field of vision, also may use its refraction na
3、ture change light the propagation direction.Therefore, accurate and fast survey transparent medium refractive index, is advantageous and plays its role in the better understanding transparent medium nature.But the light beat frequency law survey transparent medium refractive index is in optics exper
4、iment one important and the typical experiment, uses up the beat frequency to measure the speed of light is a this experimental important content, it both favors the grasping light beat frequency survey speed of light the principle, and has at the same time to the LS-III speed of light cryoscope sur
5、vey transparent medium refractive index experiment principle and the experimental technique understanding.Because the light frequency is extremely high (Hzf 14 10 ), the photoelectricity detector photosurface cannot respond the such quick luminous intensity change, it only can respond HZ 8 10 follow
6、ing luminous intensity change, and produces with this change corresponding alternation photoelectric current, therefore uses up the beat frequency the form to transform the frequency low carrier to carry on the examination. Key words: speed of light survey；photo-beat；retardation；refractometry 目 录 第 1 章 绪论 1 1.1 研究背景 . 1 1.2 研究意义 . 1 第 2 章 光速测量实验2 2.1 光速测量实验的原理 . 2 2.1.1 光拍的产生与传播 2 2.1.2 相拍二光波的获得 3 2.2 光速测量实验装置 . 4 2.2.1 光拍法测量光速的电路原理 4 2.2.2 光拍法测光速的光路 5 2.3 光速测量实验 . 6 2.3.1 测量过程 6 2.3.2
