Optical Phased Array (OPA), a manifestation of coherent beam combining (CBC), coherently integrates multiple single-mode laser beams into a unified, more powerful beam. The

individual beams are combined on the workpiece where a distinct diffraction pattern is created. The diffraction pattern can be adjusted electro-optically, by controlling the phase of each beam. Such modifications, which can be executed at a very high speed, up to 10 ns, enable the creation of many different interference shapes on the workpiece and stirring the location of the central interference lobe. The result is an ultra-fast dynamic beam laser (DBL).

In laser welding and various other material processing applications, this laser can be employed for very high speed and very accurate control of the shape and the position of the keyhole. This open a new set of degrees of freedom in stabilizing the melt pool, keyhole, design the weld geometry, and influence the solidification process.