Laboratory results of SCAO: getting ready for the EST MCAO

  1. González-Cava, José Manuel . 1
  2. Chulani, Haresh
  3. Martín, Yolanda
  4. Feijóo, Noelia
  5. Montoya, Luzma
  6. Rodríguez Delgado, Horacio
  7. Quintero, Jorge
  8. González, Francisco
  9. Hernández, Ángela
  10. Basden, Alastair
  11. Gendron, Eric
  12. Núñez Cagigal, Miguel A.
  1. 1 Universidad de La Laguna
    info

    Universidad de La Laguna

    San Cristobal de La Laguna, España

    ROR https://ror.org/01r9z8p25

Actas:
Adaptive Optics Systems VIII

Año de publicación: 2022

Congreso: Adaptive optics systems

Tipo: Aportación congreso

DOI: 10.1117/12.2628242 GOOGLE SCHOLAR

Objetivos de desarrollo sostenible

Resumen

The European Solar Telescope (EST) is a 4.2-metre telescope that will be equipped with a multi-conjugate adaptive optics (MCAO) system to provide a high spatial resolution over a circular field of view with 60” diameter. The EST-MCAO testbed is a downscaled demonstrator of solar MCAO with similar requirements to those defined for EST. It has been designed and developed to identify and better understand the capabilities of this system. Before MCAO implementation, different AO configurations must be first evaluated in the testbed. Single conjugate adaptive optics for point-like sources has been identified as the first step towards MCAO for the EST. This configuration is based on the use of a deformable mirror with 820 actuators and a Shack-Hartmann wavefront sensor with 33x33 subapertures. The main objective of this paper is to present the results obtained in the EST-MCAO testbed when testing different phase reconstruction algorithms and closed-loop schemes to deal with SCAO for point-like sources. Center of gravity technique was proposed for local slope computation when using point-like sources. Both zonal and modal approaches, including SVD and their regularized least-squares versions, were evaluated and tested for the reconstruction. A closed-loop strategy based on a proportional-integral controller was initially proposed. The benefits of pseudo open-loop control were also evaluated. The performance of the algorithms was tested considering different seeing conditions. Finally, a comparison based on RMS wavefront error and Strehl Ratio was conducted.