An Analysis of Particle-clumping Phenomena of a Charged Particle-type Reflective Electronic Display

Both the electrically positive and negative particles in a cell of quick response-liquid powder display (QR-LPD) aresurrounded by conductive electrodes on the upper and lower substrate and the dielectric materials of the barrier ribs.Particles in a cell are attached to or detached from the other materials by image force, electric field, Coulomb’s force,and Van der Waals’ force. Through these forces, the moving particles form an image but induce clumping phenomena.Particles having a large kinetic energy by a large q/m value crash into the opposite electrode with high speed at a largedriving voltage and quickly lose electrically charged material. As a result, these particles are clumped and degradepanel performance. The clumped particles in a cell are observed by microscopic photographs and ascertained bya response time. When the bias voltage is increased to 0.68-0.76 V/μm, particle clumping occurs abruptly and theresponse time increases sharply. This particle clumping is similarly observed after the number of driving times at thedriving voltage (0.42-0.64 V/μm).