An object of the present invention is to realize a numerical aperture higher than that of a pixel having a conventional construction by using a pixel circuit having a novel construction in an electro-optical device. Therefore, it is utilized that the electric potential of a gate signal line in a row except for an i-th row is set to a constant electric potential in a period except for when a gate signal line (
) in the i-th row is selected. A gate signal line
in an (i−1)-th row is also used as an electric current supply line for an EL element (
) controlled by the gate signal line (
) in the i-th row. Thus, wiring number is reduced and high numerical aperture is realized.