Nanoxerography utilizing bipolar charge patterns

We report a nanoxerography utilizing alternating bipolar surface charge patterns. Unlike a conventional nanoxerography using unipolar charge patterns, the present concept generates convex shaped equipotential planes with large curvature that can act as nanoscopic electrostatic lenses. Through these lenses, positively charged aerosol nanoparticles are focused into the center region of the negative surface charge pattern leading to the significant reduction of particle deposition width. We also demonstrate that the focusing capability can be controlled by changing ion flow rates. Numerical simulations of the trajectory and deposition of charged particles were done to support experimental results.