Characterization of the digital holographic wavefront sensor

Correction of atmospheric effects on the propagation of laser light can be achieved with adaptive optics (AO) by relying on adequate wavefront sensors. For free-space laser communications and for tracking of high-speed airborne objects, conventional wavefront sensing methods e.g. those based on the Shack-Hartmann sensor (SHS), are not always effective. Partial obscuration and saturation of the detector due to strong turbulence lead to errors in wavefront reconstruction. Another drawback of Shack-Hartmann wavefront-sensing is the timeconsuming readout of the whole detector and subsequent matrix-vector multiplication necessary to reconstruct the wavefront. We characterize a promising modal alternative: digital holographic wavefront sensor (DHWS).We examine the performance of the sensor for single-, and multimode operation and its dependence on the detector size, scintillation, residual tip/tilt and misalignments.