Vol. 37, issue 10, article # 12

Abstract:

In adaptive optics systems (AOS) applied in astrophysics, normalized cross correlation (NCC) algorithm is widely used, usually in tracking and stabilization blocks, as well as for measuring the optical parameters of AOS, for example, local tilts in wavefront sensors (WFS). Due to the tendency to increase the apertures of modern telescopes and the improvement of the resolution of digital video cameras, the problem of increasing the speed of the NCC algorithm for real-time control calculations is relevant. The article proposes a modification of the NCC algorithm for measuring the displacement of images of extended objects of a static scene in adaptive atmospheric optics applications. This type of algorithm can be used in tracking systems to eliminate jitter of the entire image, as well as for measuring the wavefront phase in WFS. Due to the simplification of the reference frame normalization procedure, the algorithm wins in speed and can be used in AOS of large-aperture solar telescopes.

Keywords:

correlation algorithm, adaptive optics, atmospheric turbulence, solar telescope, wave front

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