Rosberry F W
National Bureau of Standards, Washington, DC 20234, USA.
Appl Opt. 1966 Jun 1;5(6):961-6. doi: 10.1364/AO.5.000961.
A procedure is described for determining the inhomogeneities of a sample of optical material in terms of small changes in index of refraction at discrete points over the measured surface. The method is used in the visible- and near-ir regions of the spectrum. An He-Ne gas laser source was used for the ir measurements. The variation in index was mapped with contour lines enclosing areas of similar index variations. The largest index change in 1-cm distance was noted and recorded as the maximum variation per centimeter. Over twenty-five different samples of six different materials were examined. The results are presented in a chart indicating the range of maximum refractive index variations of the samples observed. Data are shown to illustrate the possibility of determining index values to higher precision than the material justifies.
本文描述了一种程序，用于根据测量表面上离散点处折射率的微小变化来确定光学材料样品的不均匀性。该方法用于光谱的可见光和近红外区域。红外测量使用氦氖气体激光源。折射率的变化用包围相似折射率变化区域的等高线绘制。记录并标记了1厘米距离内最大的折射率变化，记为每厘米的最大变化率。研究了六种不同材料的二十五个以上不同样品。结果以图表形式呈现，表明观察到的样品最大折射率变化范围。数据表明，确定折射率值的精度有可能高于材料本身的合理精度。
