Calculation of the Refractive Index of Glasses
The model for the refractive index, nD (λ = 589 nm), at room temperature is currently being updated for several weeks, possibly until March 2008. In the meantime, the following diagram and experimental data (110 kB) may be used for orientation. Please check back at a later time for more detailed information.
The spider-graph below shows the influences of selected glass component additions on the elastic modulus of a specific base glass, while keeping the molar ratios of all remaining components constant. The spider-graph will be different for other base glass compositions.
Figure 1: Influences of selected glass component additions on the refractive index of a specific base glass (click image to enlarge)
An interesting relation exists between the refractive indices of glasses and their densities. This relation is certainly not always linear for all glass compositions. Figure 2 shows a typical diagram that can be obtained when calculating the densities (see density model) for experimental refractive index data, or when calculating the refractive indices for the experimental density data.
Figure 2: Relation between density and refractive index, silicate and borosilicate glasses (click image to enlarge)
According to Figure 2 a relatively high refractive index and low density can be obtained with glasses containing light metal oxides such as Li2O and MgO, while the opposite trend is obtained with glasses containing PbO and BaO.