Through Optical Combiner Monitoring of Fiber Laser Processes

A new monitoring configuration for fiber laser processes is proposed. The optical emissions from process plasma/plume are directly observed through the optical combiner of the FL source making use of fast photodiodes. This solution, referred as TOCM (Through Optical Combiner Monitoring), can be easily installed on all FL sources when an optical combiner is present. Due to the optical configuration, no UV radiation from the plume is observed. Consequently monitoring can be performed only above 400 nm. Nevertheless the results obtained in monitoring welding of titanium alloys are comparable to those obtained in traditional monitoring configuration.