Figure 1
From: Contact Angle Measurement of Small Capillary Length Liquid in Super-repelled State
General methods of contact angles measurement, shown on super-repellent surfaces. (a) Static contact angle of a symmetric droplet can be measured by fitting the global droplet profile with a theoretical profile calculated from Young-Laplace equation. (b) Dynamic contact angles revealed by adding and subtracting the liquid to the droplet through a syringe needle, which tends to compromise the droplet symmetry in practice. (c) Dynamic contact angles revealed by sliding the droplet, which destroys the droplet symmetry. For (b) and (c), which lack the droplet symmetry, dynamic contact angles are usually measured by fitting the local droplet profile near the contact point with a polynomial equation.
