Adaptive optics implementation with a Fourier reconstructor

Technion - Israel Institute of Technology, H̱efa, Haifa, Israel
Applied Optics (Impact Factor: 1.78). 03/2007; 46(4):574-80. DOI: 10.1364/AO.46.000574
Source: PubMed


Adaptive optics takes its servo feedback error cue from a wavefront sensor. The common Hartmann-Shack spot grid that represents the wavefront slopes is usually analyzed by finding the spot centroids. In a novel application, we used the Fourier decomposition of a spot pattern to find deviations from grid regularity. This decomposition was performed either in the Fourier domain or in the image domain, as a demodulation of the grid of spots. We analyzed the system, built a control loop for it, and tested it thoroughly. This allowed us to close the loop on wavefront errors caused by turbulence in the optical system.

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    • "The accuracy of wavefront measurement depends on the offset estimation and the wavefront reconstructor algorithms. There are many reconstructor algorithms that may be used to improve accuracy [8] [9] [10]. However, the precision of the offset estimation is a more crucial factor [11] [12] [13]. "
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