Optical waveguide, optical module, and method for producing the same module

An optical module for causing an optical signal to branch off, or coupling optical signals, so as to propagate through an optical waveguide and an optical element, the optical module comprising:

• a first substrate having a first optical waveguide core formed therein, the first optical waveguide core being parallel to a bottom face of the first substrate;
• a second substrate having a second optical waveguide core therein, the second optical waveguide core being parallel to a top face of the second substrate;
• an optical fiber fixed to at least one of the first and second substrates;
• and
• a plurality of optical elements mounted on a part of the top face of the second substrate so as to be optically connected to an end surface of each of the first and second optical waveguide cores,
• wherein an optical connecting portion is formed between the first and second optical waveguide cores by bonding the bottom face of the first substrate to the top face of the second substrate so as to overlap with each other, the first and second waveguide cores partially being in contact with each other.