JP2509829B

PURPOSE:To eliminate the deviation in the front end position of the unit after adjustment and to eliminate the need for reteaching of a robot by constituting the unit in such a manner that the diameter of a laser spot can be adjusted without changing the overall length of the unit. CONSTITUTION:A 1st lens holding part 16 is fixed to a unit mounting plate 10 and a collimator lens 20 is held to the inner side at the front end of the holding part 16. A 2nd lens holding part 26 is loosely fitted to the outer side of the holding part 16 and a condenser lens 28 is held on the inner side at the front end of the holding part 26. An adjusting ring 42 and a lock ring 44 are screwed to the outer peripheral surface at the base end of the holding part 26. A joint part 46 having an L shape section is loosely fitted to the outer side in the intermediate part of the holding part 26 and is fixed in the intermediate part of the holding part 16. An intermediate ring 54 is fixed in the joint part 46 a nozzle 58 is fixed to the ring 54. The holding part 26 slides in the optical axis direction with respect to the holding part 16 and the lens 28 is advanced or retreated in the same direction while the lens 20 is held fixed if the ring 42 is rotated.