| 摘要 |
PURPOSE: To efficiently prevent reflection on an end surface by reducing the cross-sectional area being perpendicular in the longitudinal direction of a waveguide towards the end surface and increasing distance between the gravity center of a cross section and the center axial line of the waveguide towards the end surface. CONSTITUTION: A lower jacket layer 2 is brought up on a substrate 1 and a belt-shaped layer is provided on the layer 2 as the waveguide 3 and covered by an upper jacket layer 4. Then, the cross-sectional area being perpendicular in the longitudinal direction of the waveguide 3 is reduced towards the end surface 8 and distance between the gravity center of the cross section being perpendicular in the longitudinal direction of the waveguide 3 and the center axial line of the waveguide 3 is increased towards the end surface 8. The end surface 8 obliquely extends as against the longitudinal axial line of the waveguide 3 and the surface normal line 21 of the end surface 8 is not in parallel with the longitudinal axial line of the waveguide 3. |
