| 摘要 |
PURPOSE:To provide an optical waveguide and the producing method capable of reducing reflection loss at a joining part of polyimide optical waveguides different in refractive index. CONSTITUTION:In the waveguide composed substantially of polyimide and having the joining part of polyimides different in refractive index, a mixing layer 6 of polyimide components different in refractive index is formed on the joining part in the optical waveguide and in the producing method for the optical waveguide by applying a 1st polyamide acid solution on the substrate and after hardening and patterning, applying a 2nd polyamide acid solution different from the 1st polyamide acid solution in refractive index of the polyimide after hardening and hardening to form a final pattern, the 1st polyamide acid is hardened at 100-280 deg.C and the imidation of the 1st polyamide acid and the 2nd polyamide acid are completed at 300-400 deg.C simultaneously. |
