Patent ID: 8200058

Claim:
An optical waveguide, comprising: a core layer including core portions each having a refractive index, and cladding portions each provided adjacent to the core portions and having a refractive index lower than that of each of the core portions, the core layer containing a norbornene-based polymer, the core layer having two surfaces; and a cladding layer provided so as to make contact with at least one of the two surfaces of the core layer and having a refractive index lower than that of each of the core portions, the cladding layer formed of a material obtained by cross-linking epoxy groups of at least a part of molecules of a norbornene-based polymer directly or via compounds of a cross-linking agent as a major component thereof, wherein each of the molecules of the norbornene-based polymer of the cladding layer is represented by the following formula 1: where R is an alkyl group having a carbon number of 1 to 10, “a” is an integer of 0 to 3, “b” is an integer of 1 to 3, “p” is an integer of 1 or more, “q” is an integer of 1 or more and “p”/“q” is 20 or less.