Patent ID: 8343619

Claim:
An optical waveguide film having a cross-sectional structure wherein claddings composed of a thermoplastic resin B and dispersions (cores) composed of a thermoplastic resin A extend in a machine direction of the film and are arrayed in a transverse direction of the film, said optical waveguide film comprising not less than 8 cores, said optical wave guide film further comprising one or more core interval adjusting portions composed of the thermoplastic resin A and having a different diameter from the core diameter and a length in the transverse direction of the film of not less than 10 mm at both ends in the transverse direction of the film, and extending along the machine direction of the film in the same manner as the cores, diameters (We1, We2) of cores located at both ends in the transverse direction of the film and a diameter (Wc) of a core in a central portion in the transverse direction of the film satisfying the following Formulae (1) and (2), said optical waveguide film comprising a continuous cladding layer at at least one side thereof, thicknesses of cladding layers (Te1, Te2) at both ends thereof in the transverse direction of the film and a thickness (Tc) of the cladding layer in the central portion in the transverse direction of the film satisfying the following Formulae (3) and (4) and a core/clad area ratio in a cross section being not less than 0.5: 0.8<We1/Wc<1.2 Formula (1) 0.8<We2/Wc<1.2 Formula (2) 0.8<Te1/Tc<1.2 Formula (3) 0.8<Te2/Tc<1.2 Formula (4).