In an optical component where fixation of resin welding is performed by
emitting a laser beam to screwing parts of an inner lens barrel and an
outer lens barrel after focus adjustment, the laser beam is emitted to
melt and cure a joint of the screwing part of the inner lens barrel and
the screwing part of the outer lens barrel by 0.5 mm to 3.0 mm in a
direction parallel to a direction of protrusion of the inner lens barrel
relative to the outer lens barrel, so that welding and fixation are
completed.