Sensing more modes with fewer sub-apertures: the LIFTed Shack-Hartmann wavefront sensor
Résumé
We propose here a novel way to analyze Shack-Hartmann wavefront sensor images in order to retrieve more modes than the two centroid coordinates per sub-aperture. To do so, we use the linearized focal-plane technique (LIFT) phase retrieval method for each sub-aperture. We demonstrate that we can increase the number of modes sensed with the same computational burden per mode. For instance, we show the ability to control a 21 x 21 actuator deformable mirror using a 10 x 10 lenslet array. (C) 2014 Optical Society of America