2.3.2. Fluid Transport Evaluation

The pictures and videos for the fluid transport evaluation were taken with a Keyence microscope using two different lenses (20×–200× magnification and 100×–1000× magnification). Figure 1a shows the experimental setup for the fluid transport experiments and Figure 1b shows the setup for the fluid transition experiments with the glass lens. 1 μl of the oil was dispensed on the sample inside the textured reservoir with the help of an Eppendorf pipette. The glass lens used as a counterpart in the meniscus experiments was an uncoated plano-convex lens made of N-BK7 with the same radius of curvature as the original tribological counterpart.

**Figure 1.** Experimental setup for fluid transport evaluation. In (**a**) the setup for the fluid transport evaluation inside the laser textures is shown. The fluid propagation in the channel-like textures is observed via a microscope from the top. In (**b**) the setup for the lens experiments is illustrated. The transparent glass lens is a substitute for the tribological counterpart and allows fluid flow analysis at the transition region between channels and tribocontact.
