Conceptual description of the enhancement of electrowetting-on-dielectric (EWOD) response speed based on overdrive method. To improve response time (time to reach base radius (rb1), an overdrive voltage (V2) exceeding the target voltage (V1) is initially applied for the first frame (t1), and the target voltage (V1) is then applied for subsequent frames. This results in a reduction of the response time (t2-t1).