为了对熔石英光学玻璃应力及光学均匀性进行测试，提出一种测试用高精度折射液配制方法。根据分子结构定量关系及组分的摩尔折光度定量可加的原理，推导了折射液配比公式并制定了折射液的配比工艺；分析了折射液的折射率随测试温度和测试波长不同的变化规律，并进行了实验验证；最后分析了折射液精度对测试结果的影响。通过上述方法在实验室环境配制出与熔石英折射率匹配精度为±2×10-5的折射液；通过对粗磨光学玻璃透射比实验表明，采用该方法配制的折射液对粗磨光学玻璃在450~700 nm光谱范围内透射比从低于20%提高到97%以上；利用该方法和选用的成分配制的折射液具有毒性小、挥发性小、无色无味、长时间保存折射率保持性好的优点，可以很好地用于熔石英光学玻璃材料特性测试。

In order to measure the stress-induced birefringence and optical homogeneity of fused silica，a method of proportioning refractive index fluid is put forward. Firstly, according to the characteristic of the groups in molecules and molar refraction additivity of the two solutions, formulas for the refractivity of binary solution are analyzed and the technique is given. Secondly, dependence of the refractive index of fluid on different temperatures and wavelengths, is analyzed and verified experimentally. At last, the influence of refractive index fluid precision on test result is analyzed. According to the method, the match precision of the fluid and fused silica can be ±2×10-5; Through the experiment of rough-ground glass, the fluid can improve the transmission from below 20% to above 97% at the wavelength between 450 nm and 700 nm. The fluid which is prepared by the method and the composition we choose, has the characters of low toxicity, no color, no smell, nonvolatile, and its refractivity can remain stable for long. It can be well used for the measurement of the stress induced birefringence and optical homogeneity.