Large-guide-region wavefront sensing for solar GLAO: modeling, simulation, and experimental validation

This study explores large-guide-region wavefront sensing for solar ground-layer adaptive optics (GLAO) through theoretical modeling, simulation, and experimental validation. A correlation Shack-Hartmann wavefront sensing model based on large guide regions was developed to assess the effect of guide region size on ground-layer wavefront sensing accuracy. Simulations with the CP7 and MK8 turbulence models showed that increasing the guide region size smooths high-altitude wavefront aberrations, thus improving the detection of the ground-layer wavefront. For guide region sizes of 60′′ and 140′′, the phase RMS deviation of the ground-layer detection in GLAO was less than 1/30 of a wavelength, respectively. To further validate the model, an indoor solar GLAO experimental platform was constructed. Using phase screens to simulate various turbulence distributions, the effect of GLAO smoothing on wavefront sensing and system performance was analyzed. The experimental results confirmed that as turbulence height increased, the accuracy of ground-layer wavefront detection improved, aligning with the calculated results of the theoretical model. Additionally, the residual RMS deviation of the ground-layer between the experimental and theoretical results was less than 25nm, confirming the model’s accuracy. These findings provide valuable insights for optimizing guide region size in solar GLAO systems and advancing wide-field wavefront sensing strategies under stratified turbulence conditions.