摘要 |
A diaphragm blade includes a light-shielding, thin-plate blade base made of laser absorptive resin to regulate an aperture, and a first shaft portion made of laser transmissive resin and provided on one surface of the blade base. The first shaft portion includes a cylindrical member which is welded to the protruding weld portion, a protruding weld portion integrally formed with the blade base, and a recess formed at the back side of the protruding weld portion. The cylindrical member has a first recess defined at one end thereof near the blade base and coming into contact with the protruding weld portion, and a second recess defined at the other end. A contact surface of the protruding weld portion is melted with laser beam transmitted through the cylindrical member, whereby the protruding weld portion is welded to the cylindrical member. |