本文提出了一种自研盛装器皿以提高液体折射率的测试精度。该器皿由金属框架与等厚玻璃窗口组成, 其制造工艺相对简单, 减少了透射反射面面型精度及窗口等光程因素带来的系统误差, 提高了测试精度。本文采用的测试方法为最小偏向角法。最小偏向角法主要用于固体折射率的测试, 较少应用于液体折射率的测试。主要因为需要制作特殊的盛装器皿, 制造工艺难度大, 难以控制面型精度及透射窗口的等光程, 对测试结果造成较大影响。经过理论分析可知, 采用本文设计的盛装器皿可以满足10-6数量级的液体折射率测试需求。采用02″高精度转台进行实验, 耦合器皿带来的系统误差和测试系统的理论测量精度达10-6数量级。对某离子液在54608 nm特征谱线下实际测量的标准差为142×10-6。自研器皿满足液体折射率的精密测试需求。

A self-developed container made up of a metal frame and a glass window of equal thickness is proposed to improve the test accuracy of liquid refractive index. It improves test accuracy as the manufacturing process is relatively simple, which reduces the systematic error that arises due to the transflective surface and the equal optical path of the glass window. The test method in this paper uses the minimum deviation angle method, which is mainly used for testing solid refractive index but is less frequently applied to test liquid refractive index. Because a special container is needed, the manufacturing process is more complex, and the equal optical path length of transmission glass windows are difficult to control, which will greatly affect the test results. Using the container designed in this paper, theoretical test accuracy of liquid refractive index can reach the order of magnitudes 10-6. In the experimental case of 02″ high-precision turntable, the systematic error brought by the coupled container and the theoretical measurement accuracy of the test system can satisfy the demands in the order of magnitudes 10-6. The standard deviation of the actual measurement of an ionic liquid under the characteristic spectral line of 54608 nm is 142×10-6. The self-developing container meets the precise testing needs of the liquid refractive index.