Figure 9.

Iris concavity ratio before and after dilation in a typical experiment and three models based on the geometry of the experiment. In the realistic model (Fig. 8b), the iris curvature was similar to that of the experiment. Anteriorly positioning (Fig. 8c) or thickening of the dilator muscle (Fig. 8d) in the artificial models led to a predicted curvature inconsistent with the experimental data.