Abstract: Apparatus and method for monitoring laser materials processing, such as laser welding and laser drilling, wherein an indication of the quality of the processing is obtained by monitoring the plasma generated spaced charge distribution near the melt pool. A metal electrode, or electrodes, is disposed near the melt pool but not in contact with the workpiece, nor necessarily in contact with the hot plasma. The electric charge distribution (one dimensional or multi-dimensional) is monitored between the electrode or electrodes and the workpiece or between the electrodes themselves. The existing laser processing nozzle (insulated from the workpiece) can be used for this purpose, multi-probes such as a quadrant nozzle, can identify the focused laser beam position in real time.
Type:
Grant
Filed:
August 7, 1991
Date of Patent:
September 21, 1993
Assignee:
CMB Foodcan Public Limited Company
Inventors:
William M. Steen, Lin Li, David J. Brookfield, Qi Ning