| 摘要 |
PURPOSE:To eliminate the need for optical adjustment and to enable efficient mass production by forming a recess by etching on the clad layer or core layer prepared atop the core at the branching point of an optical waveguide to conduct the light reflected in the recess to the branch line. CONSTITUTION:The hole of a mask for etching to form a recess is matched in the part where optical waveguides 15 and 16 intersected in a T shape so as to have 45 deg. angle in the direction of 15 from a waveguide 14 from the intersected point (a) of said optical waveguides and the hole part is etched. When the hole part of the mask is then etched, a part of a clad layer 11 is etched as shown by a recessed part 13. If the part 13 is formed to decrease the thickness of the layer 11, the refractive index of the optical waveguide medium 10 right under the thinned part reflects light. As the recess 12 is obtd., the light from the waveguide 14 is partly reflected by the recess 12 and is branched to the waveguide 16. The other advances to the waveguide 15. |
