| abstract |
PROBLEM TO BE SOLVED: To provide an optical waveguide made of polyimide, in which cracks are prevented from occurring in a lower clad layer and highly reliable. An optical device comprising an under cladding layer 3, a core layer 4 provided on the under cladding layer 3, and an over cladding layer 5 provided on the under cladding layer 3 so as to cover the core layer 4. Waveguide 6, undercladding layer 3, core layer 4 and overcladding layer 5 are made of polyimide, and undercladding layer 3 is imidized with polyamic acid having a weight average molecular weight of 1.5 × 10 5 or more To form. [Selection] Figure 1 |