Figure 3.

(a) 3D simulations with different channel aspect ratios (w/h); 3.33 (left) and 0.83 (right), respectively. Perspective views of the channel with the width of 200 μm and the inlet of 150 μm. Only the left halves about the symmetry plane are shown. (b) Simulated cross-sectional views for two different inlet hole diameters at a fixed channel aspect ratio (w/h = 3.33). (c) 3D simulations for a channel of w = 100 μm and h = 100 μm, showing off–centered inlet (left), well aligned inlet (center), and slightly larger inlet (right). (d) Confocal micrographs showing cross-sectional views of vertical focusing before (A) and after (B) horizontal focusing. The top panel shows a top-view of the system near the lateral squeezing cross juction. In the bottom left panel, off-centered holes directly compare with the left panel in (c). The bottom center panel shows vertical focusing occurred in the channel of w/h = 3.33 while the sequential inlet hole size was slightly smaller. The bottom right panel shows vertical focusing occurred in the channel of w/h = 1.0.