Optical connector module

An optical connector module comprising:

• an optical transmission line comprising a core and a cladding layered on a substrate;
• an optical connector comprising a first side surface facing an end face of said optical transmission line and an end face of said substrate, wherein the optical connector is configured to couple optically to said optical transmission line;
• and
• a refractive index matching material configured to be located between said end face of said optical transmission line and said first side surface and between said end face of said substrate and said first side surface, wherein the refractive index matching material is configured to adjust a refractive index,
• wherein a first lens portion that is curved is provided on said first side surface at a position opposite said core,
• wherein said first lens portion is formed as a concave shape at said first side surface,
• wherein said refractive index matching material fills said concave shape at said first side surface and adheres to said end face of said optical transmission line, said end face of the said substrate and said first side surface.