Optical wave guide element, and manufacture therefor

[0039]In the following, the preferred embodiments of the present invention are described in detail.

[0040]Here, though an optical modulator is illustrated as an optical wave guide element in the following embodiments, the present invention is not limited to the optical modulator, but rather, it is possible to apply the present invention to an electric field sensor element, or the like, for an optical electric field sensor system. In addition, the optical modulator module is not limited to containing only an optical wave guide element, but rather, it is possible for the module to also contain a light source, such as a semiconductor laser, and a variety of optical parts or electronic parts, such as a light receiving element.

[0041]The substrate where the optical wave guide element is formed is made of a material having the electro-optic effect, such as lithium niobate (LiNbO3; hereinafter referred to as LN), lithium tantalite (LiTaO3), PLZT (lead lanthanum zirconate titanate) or a quartz-b