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Updated: Jun 16, 2026

Correction of Presbyopia by Monocular Bi-Aspheric Ablation Profile
Published on: September 20, 2024
Third order aberrations in cassegrain-type telescopes and coma correction in servo-stabilized images
Abstract:
Pointing errors in telescopes carried by space vehicles can be compensated by servo-control of the secondary mirror. This introduces some aberrations in the stabilized image, the magnitude of which depends on the asphericity of the telescope mirrors. A configuration is presented in which the centered image of an off-axis object point is free from coma. The required aspheric corrections and the residual aberrations are calculated. Also included is a summary of the third order aberration constants for some well-known centered cassegrain-type telescopes.
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