The retardation of the data was evaluated and plotted. We can see a linear dependency of retardation(effective and linear retardation) with the stretch of hydrogel. On the other hand, circular retardation and linear retardation along 45deg axis doesn't change.

The distibution of retardation was fit with gaussian fit and the mean and std was estimated. Then for each displacement the analysis was repeated to make the plot 1.

Plot 1 Retardation vs. Displacement