The present invention is a reversible electrodeposition optical modulation device employing a segmented counter electrode that permits localized areas of a continuous optical modulation electrode to be switched independently of each other. Such devices can be configured to enable practically seamless switching over the entire device for smart window and adjustable mirror applications, or to minimize cross-talk and pixel overlap for display applications. Since the electrical contacts and switching circuitry are located on the counter electrode, more active area is available for optical modulation.