Distorted wavefront detection of orbital angular momentum beams based on a Shack-Hartmann wavefront sensor.

The vortex beams carried Orbital Angular Momentum (OAM) have recently generated considerable interest due to their potential used in communication systems to increase transmission capacity and spectral efficiency. In this paper, the distorted wavefront detection based on Shack-Hartmann wavefront sensor (HWS) for the vortex beams is investigated. The detection slope of the helical phase sub-spot pattern is used as the calibrated slope zero point, and then the distortion phase of the vortex beam is detected by the HWS. Simulation and experimental results demonstrate that this method can detect the distortion phase of vortex beam with high precision and high frame rate, which is expected to accelerate the application of optical communication systems with vortex beams.