Efficient, high power laser to multi-fiber coupler for triggering optically activated switches

There are numerous applications requiring multiple high power laser beams. The simultaneous operation of more than one optically controlled high power switch such as photo-conductive, optically initiated gas, surface, and junction semiconductor, requires synchronous delivery of pulsed high power optical energy to many sites. The University of Missouri design presented here avoids the input surface damage that limits other high power division schemes and operates at the peak optical power density of the device materials. This design consists of a prism coupler, planar waveguide, and waveguide tapers fabricated on a silicon substrate. The laser beam will be spatial expanded, focused along one axis using a cylindrical lens or grating, and directed into the prism coupler. The prism coupler allows the optical energy to be coupled into the single highest mode of the planer waveguide. Actual splitting of the optical energy is accomplished by the use of multiple tapered waveguides, which are coupled to multimode fibers. Design methodology and simulation results of the proposed design will be presented.