High power high-density spectral beam combining by volume Bragg gratings

A spectral beam combiner (SBC) based on multiplexed volume Bragg gratings ( VBGs) is demonstrated and presented. A new architecture for SBC with multiple VBGs recorded into a single piece of photo-thermo-refractive (PTR) glass is presented which significantly reduces the footprint of the spectral beam combiner. For this new architecture, multiple VBGs have been recorded into one PTR glass sample. For each VBG recorded into the glass, one laser beam can be diffracted from it allowing each beam combining element to diffract multiple beams into the common beam path. A spectral beam combiner based on multiplexed VBGs is demonstrated and presented.