Angular speckle correlations and speckle removal in multimode fiber laser delivery

Summary form only given. Laser beam delivery via relatively short lengths of multimode fiber is common in remote sensing, imaging, surgery, and plasma physics. If the bandwidth of the laser in use is narrower than the coherence bandwidth of the fiber, a speckle pattern will emerge from the end of the fiber. We describe here the long-range correlations between these speckle spots, and a method to remove this speckle by modulating the launch angle into the fiber in time.