PURPOSE: To work a guide hole of an adapter for an optical fiber with high accuracy by inserting a rod forming a reflector on an inclined end surface up to a prescribed position of a main course and thrusting a branch line by a laser beam reflected by the reflector.
CONSTITUTION: The adapter 10 consists of a square thick plate-like board 11 and one side 11a of the board 11 is fixed so as to be vertical to the optical axis of a laser beam 21 projected from a laser device 20. The laser device 20 is driven and the laser beam 21 is projected to the board 11 to thrust a hole 12 penetrated from one side 11a to the other side 11b as a main course. Then, the rod 30 having an end surface 31 obliquely ground at 1/2 the branch angle θ of the branch course 13 and forming a full-reflector 40 on the end surface 31 is inserted up to the prescribed position of the main course 12 and the end surface 31 is fixed so as to be turned in the thrusting direction of the branch course 13. When the laser device 20 is actuated again, the laser beam 21 is fully reflected by the reflector 40 to thrust the branch course. Thus, the branch course 13 branched from the main course 12 and penetrated into the board can be formed.
YANAGAWA HISAHARU
KOKAYU MIKIO
