An access port assembly (10) for a main lightwave transmission fiber 16 is made by machining a notch (26) into it by carbon dioxide laser nibbling to form notch faces (28, 30) which extend into the core region (18). The end face (32) of a second, receiving fiber (12) is placed in contact with the notch faces (28) to optically couple it to the core (18) of the main fiber (16). An optical epoxy cement (34) holds the two members in position and matches the index of refraction. A third, transmitting fiber (14) is similarly connected to the main fiber (16) in a second notch and perpendicular to the receiving fiber (12).