全反射法折射率测量中的多光源光学系统设计

Design of multi-source optical system in measuring the refractive index of liquids based on total reflection

介绍了一种用于全反射法折射率测量的光学系统。当采用一个光源时,折射率测量的精度和量程受到接收面积的限制,采用多光源的光学系统,通过把量程分段,切换不同的光源来选择合适的量程,能在不改变接收端光电传感器的条件下,提高测量精度,扩大量程。本文根据折反射定律,通过分析光路图,给出了此光学系统的结构参数。理论计算和实验结果表明,当采用三个光源时,测量精度或量程比单光源系统提高到三倍左右。

A new method was developed for measuring the refractive index based on total reflection. Compared with the single-source system whose result was restricted by the receiving area, the multi-sources could improve the range and the sensitivity of the measurement without changing the receiving image sensor. Range was divided into several parts that were decided by switching the sources, The parameters of the optical structure were given by analyzing the optical pathway diagram based on formulas of refraction and reflection. The calculation and experiment showed that the range and the sensitivity of three-source system were about three times as the single-source one.