Active Optics in Astronomy: Freeform Mirror for the MESSIER Telescope Proposal
AbstractActive optics techniques in astronomy provide high imaging quality. This paper is dedicated to highly deformable active optics that can generate non-axisymmetric aspheric surfaces—or freeform surfaces—by use of a minimum number of actuators. The aspheric mirror is obtained from a single uniform load that acts over the surface of a closed-form substrate whilst under axial reaction to its elliptical perimeter ring during spherical polishing. MESSIER space proposal is a wide-field low-central-obstruction folded-two-mirror-anastigmat or here called briefly three-mirror-anastigmat (TMA) telescope. The optical design is a folded reflective Schmidt. Basic telescope features are 36 cm aperture, f/2.5, with 1.6° × 2.6° field of view and a curved field detector allowing null distortion aberration for drift-scan observations. The freeform mirror is generated by spherical stress polishing that provides super-polished freeform surfaces after elastic relaxation. Preliminary analysis required use of the optics theory of 3rd-order aberrations and elasticity theory of thin elliptical plates. Final cross-optimizations were carried out with Zemax raytracing code and Nastran FEA elasticity code in order to determine the complete geometry of a glass ceramic Zerodur deformable substrate. View Full-Text
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Lemaitre, G.R.; Vola, P.; Muslimov, E. Active Optics in Astronomy: Freeform Mirror for the MESSIER Telescope Proposal. Math. Comput. Appl. 2019, 24, 2.
Lemaitre GR, Vola P, Muslimov E. Active Optics in Astronomy: Freeform Mirror for the MESSIER Telescope Proposal. Mathematical and Computational Applications. 2019; 24(1):2.Chicago/Turabian Style
Lemaitre, Gerard R.; Vola, Pascal; Muslimov, Eduard. 2019. "Active Optics in Astronomy: Freeform Mirror for the MESSIER Telescope Proposal." Math. Comput. Appl. 24, no. 1: 2.
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