Optoelectronic unit for a laser welding monitoring system

Laser welding is being introducing for the manufacture of critical parts of engines in the aeronautical industry - among others - due to its many advantages over other welding techniques. However, process reliability must be improved; particularly, precise control of the focal point of the laser is required to ensure full penetration over the entire seam. We present an optoelectronic sensor that is able to optimize the focal position of the welding laser by monitoring the light emitted by the process in two different spectral bands and picked up by an optical fibre head. The system has been optimized for use in a real manufacturing environment. It is robust, compact, easy to operate, and able to adjust itself to different welding conditions and laser setups.