A method and system are disclosed for synthesizing an electric field. In accordance with exemplary embodiments of the present invention, an electric field that changes across a distance in space is synthesized by applying voltage levels at several locations independently of one another. The independence in voltage levels allows the electric field that is synthesized to be made periodic or aperiodic. Such a synthesized electric field can be changed at any time for use in, for example, a tunable laser. According to an exemplary embodiment, the electric field is used to change the refractive index of an electro-optic substance in an optical filter. Such an optical filter can be used as part of, for example, a wavelength agile laser, an optical add drop multiplexer, an optical switch, or the like. Such an optical filter can also be used for dynamic power balancing, dynamic gain equalization, or the like.