A window screen includes a screen sheet with two opposite outer side surfaces. Specifically, the conductive particles contained in the color toner having an electrical resistance of 1-100 cm, an aspect ratio of 10 or more, and a major axis length of 4 m or less that are distributed in the binding resin of the color toner at a weight percentage of 20 wt % or less ensure preferable properties of the color toner. Each identified group may include a plurality of electrode representations. In other embodiments, the gap is formed without affecting the surface of the substrate underlying the gap.