| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical waveguide used in an optical modulating element which is appropriately used in an optical communications system and which has high modulation efficiency, and to provide a high-frequency circuit element which realizes desired frequency and attenuation with facilitated construction. SOLUTION: In the optical waveguide 6, which has a substrate 1 composed of a material with an electro-optic effect and a ridge portion 2 on a surface of the substrate 1, the optical waveguide 6 has a periodical structure, composed of a plurality of grooves 3-1, or circular pits formed on the rear face of the substrate 1 to lower the group velocity of light propagating through the optical waveguide 6. By forming the grooves 3-1, or the circular pits on the rear face side of the substrate 1, periodical effective refractive index variation is imparted effectively to the waveguided light; and a significant effect is obtained, even with shallow grooves. Furthermore, high-efficiency optical modulation is realized, by constructing the optical modulating element using the waveguide. COPYRIGHT: (C)2006,JPO&NCIPI |
