Optical connector and optical coupling structure

An optical coupling structure comprising first and second optical connectors configured to be connected to each other, wherein

• the first and second optical connectors each comprise an optical fiber and a ferrule that holds the optical fiber, the ferrule having a flat ferrule end surface,
• the ferrule end surface of the first optical connector and the ferrule end surface of the second optical connector face each other,
• tip surfaces of the optical fibers are exposed at the respective ferrule end surfaces of the first and second optical connectors, and respective normal directions to the tip surfaces of the optical fibers and the ferrule end surfaces are inclined with respect to an optical-axis direction of the optical fibers in a section along optical axes of the optical fibers,
• the optical coupling structure further comprises a spacer configured to define a clearance between the ferrule end surface of the first optical connector and the ferrule end surface of the second optical connector, wherein the spacer has an opening configured to allow an optical path extending between the tip surface of the optical fiber of the first optical connector and the tip surface of the optical fiber of the second optical connector to pass therethrough.