OPTICAL WAVEGUIDE, ITS PRODUCTION AND OPTICAL MODULE

摘要

PROBLEM TO BE SOLVED: To obtain an optical waveguide of a wide spot at a low cost. SOLUTION: A layer 25 having an intermediate refractive index between the refractive indices of a core 23 and clads 22, 26 is disposed between both. The layer having the intermediate refractive index may be embodied as the intermediate layer 25 consisting of a third material having the intermediate refractive index between the core and the clads and may be embodied as a dispersion layer dispersed with the materials of both at the boundaries between the core and the clads. All of the core 23, the clads 22, 26 and the intermediate layer 25/the dispersion layer consist of polyimide.